Mesaba DEIS Chapter 2

Mesaba DEIS Chapter 2
2. PROPOSED ACTION AND ALTERNATIVES
2.1
INTRODUCTION
This chapter describes the Proposed Action and alternatives for the Mesaba Energy Project from the
perspectives of DOE, the project proponent (Excelsior), and the Minnesota PUC. These perspectives and
respective decisions are discussed in the balance of Section 2.1. Section 2.2 describes the technology and
principal features of Excelsior’s proposed IGCC power plant, including the process equipment, plant utility
systems, resource requirements (inputs), discharges, wastes and products (outputs), construction plans, and
operational plans, which would be common features of the project irrespective of siting. Finally, Section
2.3 describes the siting and routing alternatives considered by Excelsior for the components of the
proposed project, as well as site-specific considerations relating to the respective inputs and outputs at
alternative sites.
2.1.1
2.1.1.1
Proposed Agency Action and Alternatives Considered by DOE
DOE Proposed Action
DOE’s Proposed Action is to provide a total of $36 million in co-funding (see Section 1.3.2), through a
cooperative agreement with Excelsior, for the design and one-year operational demonstration testing period
for Phase I of the proposed two-phased Mesaba Energy Project. This first phase would be a nominal 606
MWe(net) IGCC power plant with an estimated cost of $2.16 billion (NETL, 2006a). Phase II, which would
be an identical, co-located 606 MWe plant, would be privately financed and not involve co-funding by
DOE.
A portion ($22,245,505) of the total funding has been made available for cost-sharing in the first
budget period under the cooperative agreement, prior to completion of the NEPA process. The activities
eligible for cost-sharing during the first period allow for the development of information (such as project
definition, preliminary design, and environmental studies and permitting) that provide the basis for this
EIS, consistent with DOE requirements and those of the MDOC, USACE, and USDA Forest Services.
This is typical both in the amount of funding and the types of allowable activities for a CCPI project of this
scope. Making these funds available does not prejudice DOE’s ultimate decision on the proposed action
and is consistent with DOE and CEQ regulations (10 CFR 1021.211 and 40 CFR 1506.1, respectively),
which restrict DOE from taking action that would have an adverse environmental impact or limit the
choice of reasonable alternatives until the ROD has been issued.
DOE may also provide a loan guarantee to Excelsior pursuant to EPAct of 2005 to guarantee a portion
of the private sector financing of the project; however, this potential loan guarantee is not part of DOE’s
Proposed Action. This EIS considers the impacts of both phases of the Mesaba Energy Project as
connected actions, consistent with NEPA policy, even though only Phase I would be co-funded under the
CCPI Program.
2.1.1.2
Alternatives Determined to be Reasonable by DOE
Section 102 of NEPA requires that agencies discuss the reasonable alternatives to the proposed action
in an EIS. The term “reasonable alternatives” is not self defining, but rather must be determined in the
context of the statutory purpose expressed by the underlying legislation.
2-1
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Congress established the CCPI Program with a specific goal — to accelerate commercial deployment
of advanced coal-based technologies that can generate clean, reliable, and affordable electricity in the
United States. The CCPI legislation (Pubic Law No. 107-63) has a narrow focus in directing DOE to
demonstrate technology advancements related to coal-based power generation designed to reduce the
barriers to continued and expanded use of coal. Technologies capable of producing any combination of
heat, fuels, chemicals, or other use byproducts in conjunction with power generation were considered;
however, coal is required to provide at least 75 percent of the fuel for power generation. DOE’s purpose in
considering the Proposed Action (to provide cost-shared funding) is to meet the goal of the program by
demonstrating the commercial readiness of the Conoco-Phillips E-Gas™ gasification technology in a fully
integrated and quintessential IGCC utility-scale application. Other technologies that cannot serve to carry
out the goal of the CCPI Program (e.g., natural gas, wind power, conservation) are not relevant to DOE’s
decision of whether or not to provide cost-shared funding support for the Mesaba Energy Project, and
therefore, are not reasonable alternatives.
The CCPI Program only allows for joint funding of proposed projects that have been selected through
a solicitation and negotiation process. In 2004, DOE issued the second-round CCPI solicitation. Private
sector participants submitted proposals in response to the solicitation. A group of proposals, representing
diverse technologies and using a variety of coals, was selected to further the goals of the CCPI Program.
DOE’s choices were limited by virtue of having to choose from the proposals that were submitted under
the solicitation process. The proposed project was selected under the second round of the CCPI Program
because of the opportunity to demonstrate the specific technology proposed: the Conoco-Phillips E-Gas™
gasification technology in a fully integrated and quintessential IGCC utility-scale application. Other
projects that proposed to demonstrate other technologies are not alternatives to the proposed project for
NEPA purposes.
Congress not only prescribed a narrow goal for the CCPI Program, but also directed DOE to use a
process to accomplish that goal that would involve a more limited role for the Federal government. Instead
of requiring government ownership of the demonstration project, Congress provided for cost-sharing in a
project sponsored by the private parties, with the provision for repayment of the public funds invested.
Therefore, rather than being responsible for the siting, construction and operation of the projects, DOE is
in the more limited role of evaluating CCPI project applications to determine if they meet the CCPI
Program’s goal. It is well established that an agency should take into account the needs and goals of the
applicant in determining the scope of the EIS for the applicant’s project. When an applicant’s needs and
goals are factored into the deliberations, a narrower scope of alternatives may emerge than would be the
case if the agency is the proprietor responsible for all project-related decisions.
No Action Alternative
Under the No-Action Alternative, DOE would not provide cost-shared funding to demonstrate the
commercial readiness of the Conoco-Phillips E-Gas™ gasification technology in a fully integrated and
quintessential IGCC utility-scale application (beyond funding required to complete the NEPA process). In
this case, the remaining funding withheld from the Mesaba Energy Project may be made available for other
current or future CCPI projects. In the absence of DOE funding, Excelsior could still elect to construct
and operate the proposed power plant provided that it could replace the Federal financing component and
obtain required permits from state and Federal agencies. Therefore, the DOE No-Action Alternative could
result in one of two potential scenarios:
(1) The Mesaba Energy Project would not be built.
(2) The Mesaba Energy Project would be built as planned by Excelsior.
2-2
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
DOE assumes that if Excelsior were to proceed with development in the absence of DOE funding, the
project would include all of the features, attributes and impacts as described for the Proposed Action.
However, without DOE participation, it is possible that the proposed project would be canceled. Therefore,
for the purposes of analysis in this EIS, the DOE No Action Alternative is assumed to be equivalent to a
“No Build” Alternative, meaning that environmental conditions would remain in the status quo (no new
construction, resource utilization, emissions, discharges, or wastes generated). If the project were canceled,
the proposed technology may not be demonstrated elsewhere. Consequently, eventual commercialization of
the integrated technologies would probably not occur because utilities and industries tend to use known
and demonstrated technologies rather than unproven technologies. This scenario would not contribute to
the CCPI Program goal of accelerating commercial deployment of advanced coal-based technologies that
can generate clean, reliable, and affordable electricity in the United States.
Alternative Sites
As described in Section 1.5, Excelsior is required by state regulations to consider at least two potential
sites for the proposed plant and two potential alignments for HVTLs. Excelsior’s preferred and alternative
sites and alignments are described in Section 2.3. Since DOE’s decision in this EIS relates to the funding
of a project selected competitively in accordance with objectives of the CCPI Program, DOE has not
participated in the identification or selection of alternative sites or alignments for the Mesaba Energy
Project. However, Excelsior has prepared an analysis of alternative sites within the TTRA (see Appendix
F1), in which it concludes that the West Range and East Range sites are the only practicable alternative
sites. DOE has reviewed Excelsior’s site analysis and found it to be adequate for purposes of determining
reasonable site alternatives for this EIS. Accordingly, the West and East Range sites are evaluated in detail
as reasonable alternatives. Figure 2.1-1 shows the boundary of the TTRA and the two alternative locations
(West Range Site and East Range Site) for the proposed project.
East
Range Site
West Range Site
Figure 2.1-1. West and East Range Sites in Taconite Tax Relief Area
2-3
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Alternatives Eliminated from Further Consideration
DOE considered the following alternatives in addition to the Proposed Action and No Action
Alternative. For the reasons described below, DOE elected not to carry these alternatives forward for
detailed evaluation in this EIS.
Alternative Sizes
The proposed project could be demonstrated using a smaller-sized plant; however, a smaller-sized
plant would not be sufficiently large to demonstrate the large utility-scale commercial viability of the IGCC
technology advancements, which is the central purpose of this CCPI project. The smaller-sized, single
process system IGCC plant was successfully demonstrated as part of the predecessor Clean Coal
Technology (CCT) program at the Wabash River Coal Gasification Repowering Project (Wabash) located
in Terre Haute, Indiana. Following the Wabash demonstration, a Value Improving Practices (VIP) process
– a formal industry process applying nine separate practices – was applied to examine lessons learned,
identify options to improve cost and performance, and optimize the design for application to large utilityscale commercial plant configurations. An availability target above 85 percent would be needed to
successfully compete against older technology base load facilities in the power generation industry.
Multiple process systems would be required to meet this availability requirement, including a more costeffective redundancy within the plant, low-cost back-up systems of conventional technologies, and the
integration of these features throughout the plant. The proposed project would demonstrate the large
utility-scale commercial design configuration resultant from the Wabash VIP process and subsequent
research and development consistent with the DOE IGCC Roadmap.
Alternative Technologies
DOE could demonstrate other coal gasification technologies instead of the Proposed Action; however,
such alternatives would not demonstrate the commercial readiness of the Conoco-Phillips E-Gas™
gasification technology, which is DOE’s purpose for this demonstration project.
Other Alternatives
The alternative of incorporating technologies to reduce the “carbon footprint” of the Mesaba Energy
Project was also considered. DOE recognizes that fossil fuel burning is the primary contributor to
increasing carbon dioxide (CO2) concentrations in the atmosphere (IPCC, 2001). CO2 is a significant
greenhouse gas, and increasing concentrations of greenhouse gases show correlation with global warming.
DOE recognizes that there are concerns about the effects of fossil fuel use on global climate change.
Therefore, DOE oversees other research programs aimed at reducing the cost of electricity associated with
power production and proving the viability of technologies for carbon capture and sequestration (CCS) to
reduce CO2 emissions from fossil fuel use. DOE expects that the combined efforts of these programs will
enable large-scale plants to come on-line by 2020 that offer 90 percent carbon capture with 99 percent
storage permanence at less than a 10 percent increase in the cost of energy services (NETL, 2007). The
planned in-service date for the Mesaba Energy Project is well in advance of the timeline for achieving the
DOE CCS goal.
Based on an analysis of the current feasibility of carbon capture and sequestration provided in
Appendix A2, CCS is not considered a reasonable alternative to DOE’s Proposed Action. However,
because CCS could become feasible during the commercial lifetime (at least 20 years) of the facility, DOE
has evaluated the impacts of implementing CCS during commercial operation of the project in Section
5.1.2.1 of this EIS based on the most current and representative information about available technologies.
2-4
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
2.1.2
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Proposed Project and Alternatives Considered by Excelsior
Excelsior proposes to construct and operate the 1,212-MWe (net) Mesaba Generating Station at one of
two sites in northeastern Minnesota, along with its associated support structures and utility lines. The
Mesaba Generating Station would consist of the Mesaba Energy Project (Phase I) and an identical facility
(Phase II) on the same site. Phases I and II combined are referred to as the Mesaba Generating Station.
Each phase would be rated nominally at peak to deliver 606 MWe (net) to the high voltage switchyard
located within the fenced boundary of the site. Section 2.2 describes the technology and principal features,
resource requirements, emissions, effluents, and wastes of the proposed generating station as summarized
in Table 2.1-1.
In accordance with the Proposed Action, Excelsior has entered into a cooperative agreement with DOE
under the CCPI Program to demonstrate features and technologies in the Mesaba Energy Project (Phase I)
to improve and advance IGCC processes toward commercial acceptance as described in Section 1.4.
2-5
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Table 2.1-1. Expected Operating Characteristics – Mesaba Energy Project
(Total for Phases I and II, except where noted)
Operating Characteristics
West Range Site
East Range Site
606
1,212
<606
<1,212
92
92
17,100
12,240
12,900
17,100
12,240
12,900
10,300
15,200
7,400
10,000
1,390
2,872
493
2,539
0.027
0.030
197
10.6(SB)/9.4(B)
1,390
2,872
709
2,539
0.027
0.030
197
>10.6(SB)/>9.4(B)
400
3,500
400
0
14
30
48
60
160
~4,400(GI)
14
30
48
60
160
~4,400(GI)/<24,500(PB)
1,000 – 1,600
60 – 330
1,000 – 1,600
60 – 330
a
Generating capacity (MWe)
Phase I
Total (Phases I and II)
Load Output
Capacity Factor (percent)
b
Coal consumption (tpd)
Sub-bituminous (PSQ)
Bituminous (PSQ)
Sub-bituminous/petroleum coke (50:50) (PSQ)
c
Water requirements (gpm)
Average water use (at 3 COC for West Range)
Peak water use
Air emissions (tpy)
Sulfur dioxide (SO2)
Oxides of nitrogen (NOx)
d
Particulate matter <10 microns (PM10)
Carbon monoxide (CO)
Mercury (Hg)
Lead (Pb)
Volatile organic compounds (VOCs)
e
Carbon dioxide (CO2)
Effluent discharges
f
Sanitary wastewater (gpd)
g
Cooling tower blowdown discharge (gpm)
h
Solid wastes (tpy)
Mercury removal carbon (H)
Sour water sludge (H)
Sour water carbon (H)
Syngas treatment carbon (H)
Waste char and ash (NH)
Zero Liquid Discharge (ZLD) filter cake (H)
Marketable Byproducts (tpd)
Slag (PSQ)
Sulfur (PSQ)
a
The generating capacity at the East Range Site is expected to be approximately 2 MW less than the West Range Site per phase
due to the additional load of the enhanced ZLD system at the East Range Site.
b
Peak use, both phases. Fuel flexibility allows the IGCC power plant to operate on either sub-bituminous coal, bituminous coal,
or a coal/petroleum coke blend.
c
The use of an enhanced ZLD system at the East Range Site would enable a greater number of cycles of concentration, resulting
in a lower demand for process water.
d
Because of the lower quality of water used for cooling at the East Range Site, PM10 emissions from cooling towers would be
greater than for the West Range Site.
e
CO2 emissions are a function of the feedstock consumed and of the Mesaba Generating Station’s net heat rate. SB = Subbituminous coal such as Power River Basin Coal; B = Bituminous coal such as Illinois Basin Coal; East Range Site with enhanced
ZLD system would have lower efficiency and higher emissions.
f
Discharged to publicly owned treatment works (POTWs).
g
East Range enhanced ZLD system eliminates discharge of cooling tower blowdown.
h
Fuel dependent; H = Hazardous; NH = Non-hazardous; GI = Gasification Island; PB = Power Block
gpd = gallons per day; gpm = gallons per minute; tpd = tons per day; tpy = tons per year.
PSQ = partial slurry quench mode; COC = cycles of concentration.
2-6
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
2.1.2.1
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
West Range Site and Corridors
Excelsior’s preferred site for the Mesaba Generating Station is an approximately 1,260-acre property
just north of the downtown area of Taconite in Itasca County. The project’s generating facilities would
connect to the power grid via new and existing HVTL corridors to a substation near the unincorporated
community of Blackberry. Excelsior would construct, own, and operate a new natural gas pipeline
connecting to an existing 36-inch pipeline owned by Great Lakes Gas Transmission Company (GLG) to
provide start-up and backup fuel for the station. Section 2.3 provides a discussion of the site layout and
alternative alignments considered for HVTL and gas pipeline corridors, as well as features for water
supply, rail and road access. Key features of the West Range Site and corridors are illustrated in Figure
2.1-2.
Excelsior prefers the West Range Site for the location of the Mesaba Generating Station because of its
abundant supply of water, greater distance from Class I areas, immediate proximity to two competing rail
service providers, reduced electrical losses (shorter power transmission distances than the East Range Site),
closer proximity to an abundant supply of natural gas, shorter distance via rail to the base case fuel source,
and location outside the Lake Superior Basin watershed. In addition, Excelsior holds an option agreement
for the West Range Site from a land owner having significant real estate holdings abutting the site and
across which easements for the station’s associated facilities would be required. The agreement allows for
purchase of mineral rights extending beyond the station footprint and acquisition of easements for the
associated facilities under commercially reasonable terms. Excelsior believes that the combination of the
above considerations would translate to reduced environmental impacts and project costs.
2.1.2.2
East Range Site and Corridors
Excelsior’s alternative East Range Site for the proposed Mesaba Generating Station is an
approximately 810-acre site in Hoyt Lakes, St. Louis County, approximately 1 mile north of the downtown
area. The project’s generating facilities would connect to the grid via existing HVTL corridors that lead to
a substation near the unincorporated community of Forbes. Northern Natural Gas (NNG) would construct,
own, and operate a gas pipeline as an extension of the company’s interstate pipeline system to provide
start-up and backup fuel for the station. Section 2.3 provides a discussion of the site layout and alternative
alignments considered for HVTL and gas pipeline corridors, as well as features for water supply, rail and
road access. Key features are shown in Figure 2.1-3.
2-7
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DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
5
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2-8
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9th St N
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6th St
County Hwy 102
Mineral Ave
Butler Rd
Mountain Iron
Voss Rd
1st St
18th Ave
Bo nne r Rd
Honkanen Rd
Lampi Rd Nelson Rd
Hanke Rd
Elbow Lake Rd
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Sanit Rd
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Spirit Lake Rd
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Macon Rd
Lane 57
Brown s Rd
Maury Rd
Lane 57
12th Ave W
6th
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Fraser Rd
Scout Camp Rd
Lane 51
Hoove r Rd
Peary Rd S
Lane 56
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Long Lake Rd
Fermoy Rd
Miller Trunk Rd
Haller Rd
Lane 49
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River Rd
Mac on Rd
Gavin Rd
Ad mira
Traven Rd
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Clyde Rd
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Lane 50
Stepetz Rd
Hult Rd
Lane 58-a
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Coe Rd
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US Hwy 53
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Clyde Rd
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Twp Rd 6514
Rd
Pt
s
Rd
Figure 2.1-3. East Range Site and Corridors
Deer Forest Rd
Rd
an
nt y
Co u
Pin e La
Davis Rd
d
ge R
9
t7
d
Ri d
6
tR
or
R
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66
es
rv
i
G ia
Rd
nt
nt y
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Fo
Re
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0
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DRAFT ENVIRONMENTAL IMPACT STATEMENT
2.1.2.3
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Site Selection Process and Other Alternatives Considered by Excelsior
The site selection process required several years of study that included a three-tiered siting process to
identify the most favorable location for the Mesaba Generating Station. The first tier was conducted under
a state statute enacted in 2003 (Minnesota Statutes § 216B.1694, Subdivision 1(3)) that included a
condition allowing up to three “innovative energy projects” to be located in the TTRA. Excelsior then
determined which regions throughout the TTRA have the necessary minimum infrastructure (i.e., HVTL,
water, gas, etc.), rail access, road access, and other necessary components to support the project. Once the
initial candidate areas of the TTRA were identified, a second tier of evaluation was performed that
included review of engineering feasibility, environmental compatibility, community support and
acceptance, and other criteria. The third tier of evaluation consisted of a detailed analysis of the candidate
project sites in Excelsior’s Joint Permit Application.
Excelsior documented the site screening and selection process (see Appendix F1) to support its
application to the U.S. Army Corps of Engineers for a Section 404 wetlands permit. Excelsior focused its
search on areas within the TTRA that have access to existing rail lines and provide the following features:
•
•
•
•
•
•
Availability of water for cooling and other plant purposes;
Proximity to existing HVTL corridors to minimize the environmental impacts of interconnection to
the regional electrical grid;
Feasibility of acquiring large blocks of land in a timely manner;
Reasonable distance from nearby landowners;
Reasonable proximity to a major natural gas pipeline; and
High proportion of upland to wetland areas.
These features also were used in the screening of candidate sites. Fifteen sites within the TTRA were
initially identified by Excelsior in the search and screening process. Excelsior’s document in Appendix F1
provides the rationale for eliminating sites based on the screening criteria. In summary, one site was
eliminated from further consideration based on an unsuitable grade for rail access; five sites were
eliminated based on insufficient or unproven water supplies; four sites were eliminated based on land
acquisition issues; and three sites were eliminated due to the extent of anticipated wetland impacts. The
screening process resulted in the selection of two sites, the West Range Site and the East Range Site, for
detailed evaluation.
2.1.3
Alternatives Available to the Minnesota Public Utilities Commission
As described in Section 1.4.2.3, the Mesaba Energy Project is subject to the siting and permitting
process of the Minnesota PUC. Section 1.5.2 outlines the state regulations and requirements applicable to
this process. In accordance with these requirements, and after considering the potential impacts of the
Mesaba Project, the PUC has the responsibility for taking one of the following actions:
(1) PUC may approve and issue permits for Excelsior’s preferred West Range Site and corridors.
(2) PUC may approve and issue permits for Excelsior’s alternative East Range Site and corridors.
(3) PUC may disapprove the joint permit application submitted by Excelsior.
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2.2
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
DESCRIPTION OF THE PROPOSED PROJECT
DOE would provide a total of $36 million in cost-shared funding (see Section 1.3.2) to Excelsior for
the demonstration of advanced IGCC technologies to produce electricity at commercial scale. The
proposed IGCC demonstration plant would be designed for long-term commercial operation following the
completion of an anticipated 12-month minimum demonstration period under a cooperative agreement
between DOE and Excelsior. The project would represent Phase I of the proposed two-phased Mesaba
Generating Station. As planned by Excelsior, Phase I would begin service in the fourth quarter of 2011
and Phase II would begin service in 2014. This EIS considers the impacts of both phases as connected
actions, even though only Phase I would be co-funded under DOE’s CCPI Program.
The balance of this section describes the project as proposed by Excelsior. Information contained in
this chapter of the EIS has been obtained from documents prepared by Excelsior and its contractors,
including the “Mesaba Energy Project, Joint Application to the Minnesota Public Utilities Commission for
the Following Pre-Construction Permits: Large Electric Generating Plant Site Permit, High Voltage
Transmission Line Route Permit And Natural Gas Pipeline Routing Permit” (Excelsior, 2006a) and
“Mesaba Energy Project, Environmental Supplement” (Excelsior, 2006b).
The subsections of Section 2.2 provide the following information:
•
•
•
•
•
Section 2.2.1 describes the technology selected for the Mesaba Energy Project and the various
processes included in the technology.
Section 2.2.2 describes resource requirements and inputs to the facility.
Section 2.2.3 describes discharges, wastes, and products from the facility.
Section 2.2.4 describes plans for facility construction.
Section 2.2.5 describes plans for facility operation.
2.2.1
Technology Selection and Process Description
The Mesaba Energy Project would demonstrate advanced IGCC technologies to produce electricity,
including advanced gasification and air separation systems, feedstock flexibility, improved environmental
performance characteristics, and improved thermal efficiency as described in Section 1.4.1. The
technologies would be more efficient, economical, reliable, and environmentally favorable than
conventional coal-fueled steam electric generating plants.
2.2.1.1
Technology Selection
Excelsior evaluated proposals from three companies to provide gasification technology licenses for the
project before selecting the ConocoPhillips E-Gas™ technology in the spring of 2004. Based upon
optimization analyses, Excelsior determined that the project should be designed as a “fuel-flexible” facility
capable of utilizing petroleum coke, bituminous coal, sub-bituminous coal, and certain combinations of
these feedstocks. With such capability, Excelsior determined that the design would minimize energy costs
and provide significant long-term benefits to consumers.
The gasification process for the project is based upon ConocoPhillips E-Gas technology for
gasification of solid feedstocks. The starting point for the design is the 262 MWe (net) Wabash River Coal
Gasification Repowering Project (Wabash River plant) in Terre Haute, Indiana. The Wabash River plant
was built with Federal co-funding under the DOE’s Clean Coal Technology Program (predecessor to the
CCPI) and has been in commercial operation since 1995. Following construction of the Wabash River
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2. PROPOSED ACTION AND ALTERNATIVES
plant, the DOE funded studies of potential performance and technological upgrades, which resulted in
numerous recommendations for design and operational improvements. Based in part on the DOE studies
and the lessons learned from the Wabash River facility, the Mesaba Energy Project would incorporate
several features and technologies for an advanced IGCC process. The substantial advancements being
incorporated within the E-Gas™ technology and other plant systems to be integrated and demonstrated in
the Mesaba Energy Project would constitute a third generation IGCC facility.
2.2.1.2
Integrated Gasification Combined-Cycle Technology
The project would employ integrated gasification combined-cycle technology. Gasification is the
process of converting coal, petroleum coke, or blends of these resources to a gaseous fuel called synthesis
gas (syngas). A combined-cycle electric power plant is one that uses both a steam turbine generator and a
combustion turbine generator at one location to produce electricity. Combining (integrating) the
gasification process with the combined-cycle power plant is known as IGCC, which is an inherently lowerpolluting technology to produce electricity from solid feedstocks.
Electric power for each phase of the Mesaba Energy Project would be produced in two CTGs (about
220 MWe (gross) each) and in one STG (up to 300 MWe (gross)). The combined power generation for Phases I
and II would be up to 1480 MWe (gross). The power generated would be interconnected to the regional
electrical grid by a HVTL system. Natural gas would be used to start up the IGCC power plant and as a
backup fuel.
In the E-Gas process, coal, petroleum coke, or blends of coal and petroleum coke would be crushed,
slurried with water, and pumped into a pressurized vessel (the gasifier) along with purified oxygen. In the
gasifier, controlled reactions take place, thermally converting feedstock materials into syngas. The syngas
is cooled, cleaned of contaminants, and then combusted in a combustion turbine, which is directly
connected to an electric generator. The assembly of the combustion turbine and generator is known as a
CTG. The expansion of hot combustion gases inside the combustion turbine creates rotational energy that
spins the generator and produces electricity. The hot exhaust gases exiting the CTG would pass through a
heat recovery steam generator (HRSG), which is a type of boiler, where steam is produced. The resulting
steam is piped to a steam turbine that is connected to an electric generator. The expansion of steam inside
the steam turbine spins the generator to produce an additional source of electricity.
2.2.1.3
Process Components and Major Equipment
The principal buildings associated with Phase I of the project are listed in Table 2.2-1. The major
process equipment is listed in Table 2.2-2. Figure 2.2-1 provides a block diagram showing processes and
emission sources for Phase I (Phase II essentially would be the same). Figure 2.2-2 illustrates the principal
features of the E-Gas process, which are described in the balance of this section.
Table 2.2-1. Principal Buildings Associated with Phase I of the Mesaba Generating Station
Structure
Size
Combustion Turbine Generator Building
230 ft. x 180 ft. x 75 ft. high
Steam Turbine Generator Building
170 ft. x 140 ft. x 90 ft. high
Air Separation Unit Building
375 ft. x 140 ft. x 70 ft. high
Heat Recovery Steam Generator
110 ft. x 55 ft. x 90 ft. high
Rod Mill Feed Bins
155 ft. x 25 ft. x 150 ft. high
2-12
Equipment
Capacity
Ancillary Facilities/Processes
Air Separation Unit
(2 units at 50% capacity
each)
2,507 tons per day per train, based on PRB1 coal
operation.
• N2 Booster Compressor for CTG Injection
Feedstock
(Coal/Petroleum Coke)
Handling and Storage
(1 unit at 100% capacity)
Active storage - 20 days based on PRB1 coal
• Rotary Railcar Unloading Facilities and Thaw Shed (Feedstock)
Conveying/Reclaiming based on 8,550 tons per day, as
received
• Dust collectors for enclosed feedstock storage areas
Feedstock inactive storage – 45 days based on PRB1
coal
• Liquid Oxygen and Liquid Nitrogen storage
• Truck unloading facilities (Flux)
Flux storage (silos)/conveying/reclaiming (250 tons per
day based on 50:50 blend of PRB2:PRB3 coals)
Gasification Island
(3 units at 50% capacity
each)
Coal Grinding and Slurry Preparation (2 units at 60%
capacity each)
• High Temperature Heat Recovery
Gasification (4,275 tons per day design coal, as
received, per gasifier, based on PRB1 coal)
• Slag Grinding (1 at 100% capacity)
Slag Storage and Loading System (1 at 100% capacity)
(800 tons per day (wet basis), based on 50:50 blend of
PRB2:PRB3 coals)
Syngas Treating
(2 units at 50% capacity
each)
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Table 2.2-2. Major Process Equipment
• Dry Char Removal
• Slag Dewatering (1 at 100% capacity)
• Syngas Scrubbing
• Low Temperature Syngas Cooling
• COS Hydrolysis
• Acid Gas Removal
• Acid Gas Enrichment (1 at 100% capacity)
• Mercury Removal
• Syngas Moisturization
• Sour Water System (1 at 100% capacity)
Sulfur Recovery and Tail
Gas Recycle (2 units at
50% capacity each)
Claus Plant Sulfur Recovery (O2-Blown), (Up to 83 tons
per day/train, based on high sulfur Illinois No. 6
operation)
• Molten Sulfur Storage
• Molten Sulfur Truck/Rail Loading Facilities (1 at 100% capacity)
• Tail Gas Recycle (1 at 100% capacity)
2-13
• Tank Vent Gas Incineration (1 x 100%)
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
• Recycle Gas Compression
Equipment
Power Block
Capacity
CTG (2 units at 50% capacity each) (220 MW nominal
each, based on Siemens-Westinghouse SGT6-5000F
combustion turbine assumed for environmental
permitting)
HRSG & Exhaust Stack (2 units at 50% capacity each)
STG (1 at 100% capacity), (Up to 300 MW nominal)
Ancillary Facilities/Processes
• Surface Condenser (1 at 100% capacity)
• Vacuum, Condensate and Boiler Feedwater Systems (1 at 100%
capacity)
• Power Block Circulating Water System
• Raw Water/Demineralizer Water Tankage/Pumps
• Demineralizer System
• Filtered Raw Water, Firewater/Tankage/Pumps
• Wastewater Collection/Wastewater Separation
• Plant & Instrument Air
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DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.2-2. Major Process Equipment (continued)
• Step-up Transformers
General Facilities
(1 at 100% capacity)
• Gasification/ASU Cooling Water/Tower System
• ZLD System for Gasification Island Process Waters
• ZLD System for Process Condensate Blowdown (East Range only)
• Process Condensate Blowdown Holding Tank
• Gasification Unit Flare
• Emergency Diesel Generators
• Natural Gas Distribution
• Drains and Blowdowns
• Nitrogen Distribution
• Sanitary Sewage System
• Stormwater Collection and Treatment
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MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
• Potable & Utility Water
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2. PROPOSED ACTION AND ALTERNATIVES
2-15
Figure 2.2-1. Process Block Diagram, Mesaba Energy Project
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MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Figure 2.2-2. E-Gas
 Process for IGCC Power Generation
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2. PROPOSED ACTION AND ALTERNATIVES
Other buildings associated with Phase I include the control room, administration building,
warehouse/maintenance shop, combustion turbine and steam turbine buildings, weather enclosures for the
air separation unit (ASU) compressors, slurry preparation, water treatment/laboratory, railcar thaw shed,
switchyard control room, several power distribution centers, and a visitor’s center. Phase II would consist
of a duplicate facility and would require the same structures as described for Phase I.
Feedstock Slurry Preparation
To produce slurry feedstock for the gasifier, the solid fuel would be mixed and ground with treated
recycled water and slag fines that are recycled from other areas of the plant producing slurry with a pastelike consistency. The process is illustrated in Figure 2.2-3.
Figure 2.2-3. Feedstock Grinding and Slurry Preparation
Tanks, drums, and other areas of potential atmospheric exposure of the slurry or recycle water would
be covered and vented into the tank vent collection system for vapor emission control. The entire
feedstock grinding and slurry preparation facility would be paved and curbed to contain spills, leaks, wash
down, and stormwater runoff. A trench system would carry this water to a sump where it would be
pumped into the recycle water storage tank.
Gasification and Slag Handling
The gasifier consists of two stages: a slagging first stage, and an entrained flow, non-slagging second
stage. Unlike traditional pulverized coal power plants, where fuel is actually combusted, in an IGCC
power plant, slurry is fed to the gasifier along with sub-stoichiometric oxygen (O2) at an elevated
temperature and pressure. The feedstock would be almost totally gasified in this environment to form
syngas consisting principally of H2, carbon monoxide (CO), carbon dioxide (CO2), and water (H2O).
Figure 2.2-4 illustrates the process. Each phase of the Mesaba Energy Project would include three
gasification systems.
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MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
SULFUR RECOVERY
Figure 2.2-4. Gasification and Slag Handling
Most of the sulfur in the feedstock is converted to hydrogen sulfide (H2S) during gasification, although
a small portion of the sulfur is converted into carbonyl sulfide (COS). Most of the nitrogen in the
feedstock is converted to ammonia (NH3). The energy in the feedstock is ultimately converted into CO and
H2 with a small amount of methane (CH4). Low-grade coals with lower heating values and higher moisture
contents would generate a syngas with more CO2 and H2. Higher quality coals and petroleum coke would
result in a syngas that has a much higher CO content. Further processing of the syngas would remove
over 99 percent of the sulfur from high-sulfur feedstocks and over 97 percent of the sulfur from low-sulfur,
sub-bituminous coal feedstocks. The lower removal rate from low-sulfur coal would result in
approximately equal sulfur emissions rates as the higher removal rate from higher sulfur coal. Hence, the
final SO2 emission rate achieved using E-Gas™ technology would be independent of the starting sulfur
concentration in the feedstock.
Mineral matter in the feedstock and any added flux forms a molten slag, which flows continuously into
a water-quench bath. The characteristics of the slag produced in the gasifier would vary with the mineral
matter content of the feedstock. The slag/water slurry would then be directed to a dewatering and handling
area. Slag production at full load would vary from about 500 tons per day up to a maximum of about 800
tons per day per phase depending upon the ash content of the coal or petroleum coke received. The slag
would be dewatered at the facility and transported via rail or truck to market or storage. Section 2.2.3.4
discusses the marketable byproducts of the Mesaba Energy Project, including slag. The impacts associated
with materials and waste management during plant operations are described in Section 4.16.2.2.
The raw syngas generated in the first stage flows into the second stage of the gasifier. The gasifier
second stage is a vertical refractory-lined vessel in which additional slurry would be reacted with the hot
syngas stream exiting the first stage. The feedstock undergoes devolatilization (separation of organic
components) and pyrolysis (high temperature decomposition), thereby generating more syngas with higher
heat content (less carbon being converted to CO2), because no additional O2 would be introduced into the
second stage. This additional slurry lowers the temperature of the syngas exiting the first stage by the
endothermic nature of the devolatilization and pyrolysis reactions. Also, water reacts with a portion of the
carbon to produce additional CO, CO2, and H2 for subsequent use as syngas fuel for power generation.
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MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Unreacted solid fuel (char) would be carried out of the second stage with the syngas. Certain metals
present in the feedstocks in trace quantities and volatile at the temperatures typical of the gasifier would be
carried out in their gaseous state as components of the syngas and removed in the cleanup stage. The
slag/water slurry would flow continuously into a dewatering bin. The bulk of the slag would settle out in
the bin while water overflows into a basin in which the remaining slag fines would settle. The clear water
from the settler would pass through heat exchangers where it would be cooled as the final step before
being returned to the gasifier quench section. Dewatered slag would be transferred to the slag storage area
to be loaded into trucks or rail cars for transport to market or storage. The slurry of fine slag particles from
the bottom of the settler would be recycled to the slurry preparation area to be fed back into the gasifier to
maximize carbon utilization.
Syngas Cleanup and Desulfurization
The syngas cleanup and desulfurization systems include the processes for syngas cooling, particulate
matter removal, syngas scrubbing, acid gas removal, mercury removal, and potential future retrofit for
carbon capture as described in the following paragraphs. In syngas cooling, the hot raw syngas exiting the
gasifier system would be cooled converting a significant portion of the heat from the gasifier to highpressure steam via heat exchangers for use in power generation. After cooling, the syngas (including
entrained particulate matter containing carbon that remains available for gasification) would be directed to
the particulate matter removal system, as shown in Figure 2.2-5. The gas flows first through a hot gas
cyclone for removal of relatively large particles and then passes to the particulate matter filter. The filter
vessel contains numerous porous filter elements to remove particulate matter from the syngas (>99.9
percent removal efficiency). Removed particulate matter from both the hot gas cyclone and the dry filter
vessel would be recycled to the first stage of the gasifier to further convert particle-bound carbon to syngas
and thereby improve carbon conversion efficiency. Continually recycling captured particulate matter to the
gasifier promotes higher thermal efficiencies and lowers the carbon content of the slag, making the slag
more marketable. Generally, less than one percent of the carbon originally present in the feedstock would
be expected to end up in the slag confirming that near complete gasification of the carbon content of the
feedstock would be obtained. The particle-free syngas would then proceed to the low temperature heat
recovery system.
Figure 2.2-5. Particulate Matter Removal
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MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Next, the syngas would be scrubbed with recycled sour water (water with dissolved sulfur compounds
and other contaminants condensed from the syngas) to remove chlorides and trace metals and to reduce the
potential for equipment corrosion and formation of undesirable products in the acid gas removal (AGR)
system. A COS hydrolysis unit would be incorporated to achieve a high level of sulfur removal, which
would convert the small amount of COS in the syngas to H2S that could then be efficiently removed in the
AGR system.
After hydrolysis, the syngas would be cooled in process heat exchangers to efficiently utilize the
relatively low-temperature heat available. Most of the NH3 and a small portion of the CO2 and H2S present
in the syngas would be absorbed in the water condensed by this cooling step. Additionally, some of the
trace metals that remained in their gaseous state during the particulate matter removal process would
condense. The water would be collected and sent to the sour water treatment unit. The cooled sour syngas
would be fed to the AGR system, where the sulfur compounds would be removed to produce a low-sulfur
product syngas. The syngas scrubbing process is illustrated in Figure 2.2-6. Each phase of the Mesaba
Energy Project would include two gas treatment systems.
15
ACID GAS
REMOVAL
HEAT TO PROCESS
COS
HYDROLIZER
COOLERS
COOLER
SOUR WATER
TREATMENT
Figure 2.2-6. Syngas Scrubbing
The AGR system (Figure 2.2-7) would cause the cool sour syngas to contact an aqueous solution of
methyl-diethanolamine (MDEA), which is an amine absorbent that would remove the H2S to produce a
clean product syngas. The H2S-rich MDEA from the bottom of the absorber would flow to a cross heat
exchanger to recover heat. The heated rich MDEA would then be directed to the H2S stripper where the
H2S and CO2 are removed at near atmospheric pressure. A concentrated stream of H2S and CO2 would exit
the top of the H2S stripper and flow either to the carbon-capture system or directly to the sulfur recovery
unit. The lean MDEA would be pumped from the bottom of the stripper to the heat exchanger. The lean
MDEA would be further cooled before being stored and then recirculated to the absorber. This unit is a
totally enclosed process with no discharges to the atmosphere.
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MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Mercury Removal and Moisturization
After removal of sulfur, the syngas would pass through fixed beds of activated carbon prepared with a
special impregnate to remove mercury (Figure 2.2-7). Each phase of the Mesaba Energy Project would
have two mercury removal units. Multiple beds would be used to obtain optimized adsorption. The lower
temperature and lower moisture content of the syngas after the AGR would allow the carbon beds to
operate at high efficiencies. The activated carbon capacity for mercury ranges up to 20 percent by weight
of the carbon (Parsons, 2002). The mercury removal system would remove enough mercury from the
syngas so that the mercury content of the syngas fuel would be no more than 10 percent of the mercury
contained in the solid IGCC feedstock. After mercury removal, the product syngas would be moisturized,
heated, and diluted with nitrogen for control of nitrogen oxides (NOx) before being used as fuel for power
generation in the CTGs.
Figure 2.2-7. Acid Gas Removal and Mercury Removal
Potential Carbon Capture Retrofit
Global emissions of CO2 resulting from fuel combustion have
The Mesaba Energy
increased from 16 billion tons in 1973 to 27 billion tons in 2005 (IEA,
Project design would
2007). Another study estimated global emissions of CO2 from fuel
enable a potential carbon
combustion to be 28 billion tons in 2003 (Marland et al., 2006).
capture retrofit if
Although CO2 emissions from power plants are not currently regulated
reductions in CO2
emissions become
under the Clean Air Act, concerns about global warming may result in
regulated or economically
future controls on emissions of this greenhouse gas. Therefore, the plant
favorable in the future.
would be designed so that it could be modified to allow for the capture of
CO2 in the event that reductions in these emissions are required by
regulation or encouraged by economic incentives at some time. Because the implementation of carbon
dioxide capture and storage technologies for the Mesaba Energy Project is not included in the DOE
demonstration project for the CCPI Program (as explained in Section 2.1.1.2), the potential impacts from
implementing these technologies are addressed within Section 5.1.2.1 as aspects of the commercial
operation of the power station.
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MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
There are two primary options for the capture of CO2 in this power plant: (1) removal of CO2 present
in the syngas itself, prior to combustion; and (2) converting CO in the syngas to CO2 by catalyzing CO and
water into CO2 and H2. Under the first option, the removal of CO2 from the syngas would result in roughly
a 30 percent reduction in overall CO2 emissions from the power plant. This would be accomplished by the
installation of amine scrubbers upstream or downstream of the acid gas removal system in the IGCC. This
approach would remove up to 85 percent of the CO2 in the syngas that fuels the plant and result in an
overall CO2 capture rate of 30 percent from the plant. The technology for this option is currently available
and could be implemented as early as 2014, following the commercial operation date of Mesaba Phase I, if
required by regulation or encouraged by economic incentives. The CO2 capture facilities would likely be
located within the existing site requiring an area of approximately 100 by 150 feet to accommodate
necessary equipment.
For the second CO2 removal option, the technology to remove the CO2 from the combustion gases is
not currently available commercially, but will be demonstrated in the near future as part of DOE’s
FutureGen Project. This technology would likely increase the capital cost and reduce overall efficiency of
the plant, making it more expensive than the first option (30 percent removal). However, the
implementation of the first option does not preclude the potential implementation of the second option at
some point in the future. Additionally, the project proponent has performed a preliminary study of
potential storage (or sequestration) of the carbon dioxide emissions (see Appendix A1). Excelsior has
contracted with the Plains CO2 Reduction Partnership (one of seven regional partnerships funded by
DOE’s Regional Carbon Sequestration Partnership Program) to investigate and, if possible, produce a CO2
sequestration/mitigation plan. As a part of its 4-year Phase II Studies initiated in 2005, the Plains CO2
Reduction Partnership would seek to produce a CO2 management plan specifying conditions required by
potential purchasers of CO2.
There are two basic carbon sequestration options: (1) use the captured CO2 for enhanced oil recovery
(EOR); and (2) store the captured CO2 within a compatible geologic formation. Both of these options
would require the construction of a CO2 pipeline system to convey the pressurized gas from the Mesaba
Energy Project to the sequestration site(s). CO2 has proven to be very effective for secondary and tertiary
oil recovery by both displacing and decreasing the viscosity of otherwise unrecoverable oil. Under the first
carbon sequestration option, the captured CO2 would be pressurized and transported to existing oil fields in
north central North Dakota and southwestern Manitoba. This option would require the construction of at
least 405 miles of pipeline to convey the gas to sequestration sites required to accommodate the CO2. The
captured CO2 could also be stored in geologic formations that act as CO2 sinks, which are typically saline
formations. Under the second sequestration option, the captured CO2 would be conveyed via pipeline, to a
suitable saline formation located approximately 265 miles from the Mesaba Energy Project area in eastern
North Dakota.
All of the CCS options presented above are based on a potential future requirement to reduce CO2
emissions from the Mesaba Energy Project, along with the potential for financial incentives (such as
carbon removal credits) that would limit the costs of capture/sequestration from being entirely borne by the
utility customers. See Appendix A1 “Excelsior’s Plan for Carbon Capture and Sequestration” and
Appendix A2 “DOE Analysis of Feasibility of Carbon Capture and Sequestration for the Mesaba Energy
Project.”
Based on an analysis of the commercial readiness of carbon capture and sequestration presented in
Appendix A2, CCS is not considered technically or economically feasible for the Mesaba Energy Project at
this time. While both carbon capture and carbon dioxide transport are technically feasible, the technical
feasibility of carbon sequestration for the Mesaba Energy Project cannot be validated in the near-term until
extensive field tests are conducted to fully characterize potential storage sites and the long-term storage of
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2. PROPOSED ACTION AND ALTERNATIVES
sequestered carbon has been demonstrated and verified through ongoing efforts conducted under the DOE
Carbon Sequestration Program.
Furthermore, commercially available combustion gas turbines envisioned for this project cannot
operate on carbon monoxide-depleted syngas where the hydrogen concentration approaches 100 percent.
With regard to economic feasibility, imposition of CCS on the project would increase the cost of electricity
such that the Mesaba Energy Project would not be economically viable without an order from the PUC that
incorporates the costs associated with CCS within the power purchase agreement. However, the design
and construction of the facility would be compatible with future implementation of any of the carbon
capture and sequestration options currently being considered.
Sulfur Recovery
The H2S carried along in the acid-gas from the AGR system would be converted to elemental sulfur in
the sulfur recovery unit (SRU) as illustrated in Figure 2.2-8. Each phase of the Mesaba Energy Project
would include two SRUs. The sulfur would be condensed and collected in molten form and could be sold
as a by-product raw material for fertilizer or other beneficial uses. The tail gas from the SRU is composed
mostly of CO2 and nitrogen with trace amounts of H2S and SO2 as it exits the last condenser. The liquid
sulfur would be pumped from the sulfur pit to a sulfur-degassing unit. The sulfur-degassing unit strips
dissolved H2S out of the liquid sulfur. The degassed sulfur would be pumped from the degassing unit to
the sulfur storage tank. The stripped H2S stream is routed to the tail gas recycle stream to the gasifier.
Liquid sulfur from the sulfur storage would be pumped to trucks or rail cars. The sulfur loading equipment
would include vapor recovery systems to control fugitive emissions by returning displaced vapors to the
storage tank. The SRU is a totally enclosed process with no discharges to the atmosphere.
Figure 2.2-8. Sulfur Recovery Unit
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2. PROPOSED ACTION AND ALTERNATIVES
Air Separation
The ASU would provide oxygen for the gasification process and nitrogen for CTG NOx control and for
purging. The ASU contains an air compression system, an air separation cryogenic distillation system
(“cold box”), an oxygen pump system and a nitrogen compression system. Two ASU equipment trains
would be provided for each phase of the facility. A multi-stage, electric motor-driven centrifugal
compressor would compress filtered atmospheric air that may be combined with additional compressed air
extracted from the gas turbines in the power block. The combined air stream would be cooled and directed
to the molecular sieve absorbers where moisture, CO2 and atmospheric contaminants are removed to
prevent them from freezing in the colder sections of the plant. The dry CO2-free air would be separated
into O2 and nitrogen gas (N2) in the cryogenic distillation system. A stream containing mostly oxygen
would be discharged from the cold box as a liquid and stored in an intermediate oxygen storage tank, from
which it would be fed to the gasifier.
The remaining portion of air mainly containing nitrogen would leave the ASU in three separate
nitrogen streams. A small portion of high-purity nitrogen would be used in the gasification plant for
purging and inert blanketing of vessels and tanks. The largest, but less-pure, portion of the nitrogen would
be compressed and sent to the combustion turbines for NOx emission control. A waste/excess nitrogen
stream would be vented to the atmosphere. There would be no emission of regulated air pollutants from
the ASU.
Slag Handling, Storage & Loading
The slag/water slurry from the gasifier (see Figure 2.2-4) would flow continuously into a dewatering
system where slag would be removed in a two-phased settling process. The clear water from the settler
would be passed through heat exchangers where it would be cooled as the final step before being returned
to the gasifier quench section. Dewatered slag would be transferred by in-plant trucks to the slag storage
area to be loaded into on-road trucks or rail cars for transport to market or storage. The dewatered slag
would be relatively inert and very moist, and it would not be a source of fugitive emissions.
Combined-Cycle Power Block
The power generation portion of the Mesaba Generating Station would be similar to a conventional
natural gas combined-cycle plant, which is one of the most efficient commercial electricity generation
technologies currently available. Each phase of the station (Phase I and Phase II ) would include two
advanced (F Class) CTGs configured to utilize syngas, two HRSGs, and a single STG. Each plant phase
would convert the chemical energy contained in the syngas fuel to electricity both directly, through
combustion, and indirectly, through steam generation.
In the process, preheated syngas from the gasification section would be mixed with compressed air and
supplied to the combustor of the CTG. Diluent nitrogen added to the syngas fuel would reduce the flame
temperature in the combustor and thereby reduce the production of nitrogen oxides. The hot exhaust gas
exiting the combustor would flow to the expander turbine driving the generator to produce electricity and
also turning the air compressor section of the combustion turbine. Hot exhaust gas from the expander
would be ducted through the HRSG to generate high-energy steam used to produce additional electricity in
the STG. The HRSG would generate three pressure levels of steam and also heat boiler feed water for the
syngas cooler in the gasification section. Following heat recovery, the cooled exhaust gas would be
discharged to the atmosphere through the HRSG stacks. The HRSG stacks would include emission
monitoring instruments as required to verify compliance with applicable emission standards and permit
conditions.
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2.2.1.4
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Plant Utility Systems
Tank Vent Boiler System
A tank vent system would be used to convert each off-gas component in the tank vents to its oxidized
form (SO2, NOx, H2O, and CO2) before venting them to the atmosphere. The tank vent streams would be
composed primarily of air purged through various in-process storage tanks and, with the exception of the
off-gas from the slag handling dewatering system, would be routed to the tank vent boiler (TVB). The tank
purge gas may contain very small amounts of sulfur-bearing components. The high temperature produced
in the TVB would thermally convert any H2S present in the tank vents to SO2. Heat recovery (in the form
of steam generation) would be provided for the hot exhaust gas from the TVB before it is directed to a
stack and emitted. Since the slag handling dewatering system off-gas contains high H2S concentrations, it
would be recycled to the gasifier to eliminate a potential source of SO2 emissions if released to the tank
vent system.
Sour Water Treatment
Water reuse within the gasification plant would minimize water consumption and discharge. Process
water containing dissolved contaminant gases produced within the gasification process must be treated to
remove dissolved gases before being recycled to the coal grinding and slurry preparation area or being
diverted to the Zero Liquid Discharge (ZLD) system.
The dissolved gases would be driven from the water by steam-stripping. Water condensed during
cooling of the sour syngas would contain small amounts of dissolved gases (CO2, NH3, and H2S) and other
trace contaminants, which would be stripped from the sour water in a two-step process as illustrated in
Figure 2.2-9. The CO2 and most of the H2S would be removed in the CO2 stripper and directed to the
SRU. The water exiting the bottom of this column would be cooled, and most would be recycled in the
feedstock grinding and slurry preparation. The remaining water would be treated in the NH3 stripper to
remove the ammonia and remaining trace components. The stripped ammonia would be combined with
the recycled slurry water. A portion of the treated water from the NH3 stripper would be blown down to the
ZLD system; the rest would be reused within the plant. The sour water treatment system would be a totally
enclosed process with no discharges to the atmosphere.
Zero Liquid Discharge (ZLD) System
At either the West Range or East Range location for the generating station, treated water from the NH3
stripper in the gasification process would be released to a ZLD system. The blowdown stream would be
pumped to a brine concentrator that uses steam to indirectly heat and evaporate water from the wastewater
stream. Resulting water vapor would be compressed and condensed, and the high quality distillate would
be recycled to the syngas moisturization system. The concentrated brine would be further processed in a
heated rotary drum dryer. There the remaining water would be vaporized and a solid filter cake material
collected for appropriate disposal. The use of the ZLD system would prevent the contaminants in the
feedstocks from being discharged to receiving waters. For the East Range Site only, an enhanced ZLD
system would also treat cooling tower blowdown to eliminate all direct wastewater discharges to receiving
waters as necessitated by the stringent requirements applying to discharges of mercury in the Lake Superior
Basin watershed.
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2. PROPOSED ACTION AND ALTERNATIVES
REUSE OR
ZLD
UNRECOVER
Figure 2.2-9. Sour Water Treatment System
Auxiliary Boilers
Two auxiliary boilers, one for each phase of the Mesaba Generating Station, would provide steam for
pre-startup equipment warm up and for other miscellaneous purposes when steam from the gasifiers or
HRSGs is not available. The boilers would provide steam in addition to, or in lieu of, the steam that would
be generated from the TVBs. Each boiler would produce a maximum of about 100,000 pounds per hour of
steam and would be fueled by natural gas. Annual operation of each boiler would be equivalent to or less
than 25 percent of the year at maximum capacity. Boilers would be equipped with low NOx burners to
minimize emissions.
Flare
During unit startup or during short-term combustion turbine outages, an elevated flare at the
gasification island would be used to burn off partially combusted natural gas and scrubbed/desulfurized
off-specification syngas. Syngas sent to the flare during normal planned flaring events would be filtered,
water-scrubbed, and further treated in the AGR and mercury removal systems to remove regulated
contaminants prior to flaring. Flaring of untreated syngas or other streams would only occur as an
emergency safety measure during unplanned plant upsets or equipment failures.
Emergency Diesel Engines
A 2-MW emergency diesel generator would be used for the gasification island and a 350-kW
emergency diesel generator would be used for the power block. One or two nominal 300-horsepower
diesel-driven firewater pumps would be provided for each plant phase. These engines would burn very
low sulfur distillate oil. Other than for plant emergency situations, each engine would be operated less
than five hours per month for routine testing, maintenance, and inspection purposes.
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2.2.2
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Resource Requirements (and Inputs)
The primary resource requirements for the Mesaba Generating Station (Phases I and II) would include
feedstock, natural gas, process water, infrastructure, transportation facilities, and land area. Each resource
is discussed in general terms below. Specific sources for these inputs for the West Range Site and the East
Range Site are described in Sections 2.3.1 and 2.3.2, respectively. Resources required for construction of
the Mesaba Generating Station are discussed in Section 2.2.4, Construction Plans.
2.2.2.1
Feedstock Requirements
The Mesaba Generating Station would be designed to be “fuel
flexible,” which means it could operate at or near maximum
capacity using various fuels or blends of fuels. This would provide
future cost benefits, because it would allow the station to adapt its
fuel mix over the life of the facility thereby minimizing the cost of
power. Fuel flexibility would also reduce the dependence on a
single fuel supplier or transportation provider.
The Mesaba Generating Station
could operate using bituminous
coal, sub-bituminous coal,
coal/petroleum coke blends, or
other blends of these fuels. This
fuel flexibility would allow the
facility to minimize the cost of
power.
The facility would be designed to utilize the following fuels:
•
•
•
•
Bituminous coal (e.g., Illinois No. 6) up to 100 percent;
Sub-bituminous coal (e.g., Powder River Basin [PRB]) up to 100 percent;
Petroleum coke blended up to 50 percent with coal; or
Blends of these fuels.
Coal and petroleum coke are typically characterized by their heating value, elemental analysis (percent
carbon, hydrogen, nitrogen and sulfur by weight), mineral matter (known as ash), and moisture content.
Phase I would utilize approximately 2.7 million tons of feedstock annually assuming operation at 90
percent capacity. Under maximum feedstock input, and assuming the gasifiers operated in full slurry
quench (FSQ) mode, each phase would require a maximum of 8,230 tons of coal (sub-bituminous) per day
on an as-received basis. Assuming partial slurry quench (PSQ) operation of the gasifiers, the daily
maximum would increase to 8,550 tons on an as-received basis, or about 3 million tons of feedstock per
year. With Phase I and Phase II operating at full load with the gasifiers in FSQ mode, a maximum 16,460
tons of coal feedstock per day would be consumed. With the gasifiers operating in PSQ mode at full load,
Phase I and Phase II would require a maximum of about 17,100 tons of sub-bituminous coal per day.
Operating in FSQ mode would result in reduced fuel use and, consequently, reduced pollutant
emissions/discharges, and Excelsior intends to operate the Mesaba Energy Project in the more-efficient
FSQ mode to the extent feasible. However, FSQ is an IGCC design improvement that is subject to further
engineering and verification by experience at Wabash River. Therefore, to avoid unrealistic expectations,
neither the maximum resource requirements nor maximum pollutant emissions/discharges operating under
FSQ are considered in this EIS.
Coal and petroleum coke feedstocks would normally be received by rail in dedicated unit trains from a
mine (or refinery). The proposed onsite rail line would be designed based on the following assumptions:
•
•
Unit trains would include up to 135 cars (the average unit train shipment would be comprised of
115 cars).
Each unit train car would carry an average of 119 tons of feedstock.
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•
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
A maximum of three unit trains per day (midnight to midnight) could be received and unloaded
based on an unloading rate of four hours per train.
Unloading facilities would include a thawing shed to loosen frozen cargo during the winter season, and
a partially enclosed rotary car dumping system with an automatic electro-hydraulic positioning system,
which would reduce the run time and associated emissions of the locomotive or switch engine during the
entire unloading process. Feedstock materials would fall from the rotated cars into an enclosed unloading
pit and would be transferred via a feeder/conveyor system to active storage pile stackers. Four active
storage piles for each phase (a total of eight for the Mesaba Generating Station) would provide working
feedstock storage. Reclaimers and conveyors would move coal/coke from the active piles to the slurry feed
preparation area. Additional inactive storage would be located on the opposite side of the rail sidings to
provide a reserve source of feedstock material in the event normal deliveries of unit trains are interrupted.
If needed, feedstock from the inactive pile would be moved by mobile equipment (bulldozers, scrapers,
and/or front-end loaders) to the unloading pit.
The feedstock handling system would include facilities necessary to unload solid feedstock materials,
convey them to storage areas, store them until required, reclaim them from storage, blend them as
necessary, and convey the blended materials to the slurry preparation system. On-site storage facilities
would be provided for two feedstock materials: coal and petroleum coke. Storage facilities would also be
provided for flux, which is a feedstock-conditioning material, described below. The feedstock storage
facilities would include, for each phase of the generating station, approximately 20 days of active storage
and approximately 25 days of inactive storage. The storage areas would incorporate dust suppression
systems (including covered conveyers and other enclosures, dust suppression sprays, and vent filters) and
would be paved, lined, or otherwise controlled to enable collection and treatment of stormwater runoff and
prevent infiltration of chemical species leached from feedstock materials and/or flux to groundwater.
At the high operating temperatures of the E-Gas gasifier, ash in feedstock material would normally
melt and drain to the bottom of the gasifier where it would be removed as molten slag and cooled in a
water bath until it solidified. Mineral matter in the ash determines the melting temperature of the slag and
its viscosity at a specific operating temperature. If too viscous, the slag would not easily flow from the
gasifier and could potentially plug the bottom. If too fluid, the slag could be excessively erosive to the
refractory in the gasifier. Flux, typically silica/sand, limestone, iron oxide, or a mixture of these materials,
would be blended with the feedstock under carefully monitored conditions to control the slag melting point
and viscosity.
Flux would be received by truck (or railcar) and pneumatically conveyed to enclosed storage silos
equipped with fabric filters for dust control. Flux from storage silos would be automatically blended with
feedstock by a weigh belt feeder system. The required quantity of flux would be a small fraction of the
total feed, typically less than 250 tons per day per phase.
2.2.2.2
Natural Gas Requirements
Although the primary fuel source for electric power production would be coal-derived syngas, the
Mesaba Generating Station would also be capable of operating on natural gas. Natural gas would be used
during startup of the facility and as a backup fuel. This ability to operate on natural gas would provide an
additional source of available generating capacity (and reliability for periods when the gasification island is
unavailable). In addition, it would offer the option of installing the combined-cycle power island early in
the construction process (that is, ahead of the gasification island), thereby allowing for electricity
production from natural gas until the gasification island could be installed and the unit would begin full
baseload operation on coal-derived syngas. Although not currently planned for the Mesaba Energy Project
(Phase I), the ability to come online early using natural gas would be a very useful resource planning
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option for Phase II. Excelsior has proposed permits to allow for natural gas firing at capacity factors of 30
percent, 20 percent, 10 percent, and 5 percent for years 1, 2, 3, and thereafter, respectively. The expected
maximum natural gas flow would be about 105 million standard cubic feet of gas per day per phase of the
Mesaba Generating Station.
Two major natural gas pipeline transmission companies serve Minnesota’s Iron Range: GLG and
NNG. The GLG natural gas pipeline system interconnects with NNG’s natural gas pipeline system near
Carlton, Minnesota. Section 2.3 describes the gas pipeline interconnection alternatives for the West Range
and East Range Sites.
2.2.2.3
Process Water Requirements
The Mesaba Generating Station would require process water for the following purposes:
•
•
•
•
As the prime mover in the steam cycle (Raw water must be treated to ultra purity standards to be
used in the HRSG for steam production. The steam produced in the HRSGs is delivered to the
steam turbine and condensed for reuse.);
To condense steam used in the power cycle (Water used for steam production in the HRSGs would
be of very high quality and, for economic reasons, would not simply be vented to the atmosphere
as low grade steam.);
To slurry coal for feed to the gasifier; and
For various other contact/non-contact cooling purposes.
Water requirements for the Mesaba Generating Station would differ somewhat depending on the siting
of the project for reasons explained in Section 2.3. The average and peak water requirements are indicated
in Table 2.2-3. Peak rates would occur on hot, humid days and would be projected to reach 5,000 to 6,500
gallons per minute per phase or 10,000 to 15,200 gallons per minute for both phases on such days.
Table 2.2-3. Process Water Requirements
West Range Site
Phase
a
East Range Site
Average Annual
Demand (gpm
b
[cfs])
Peak Demand
(gpm [cfs])
Average Annual
Demand (gpm
[cfs])
Peak Demand
(gpm [cfs])
Mesaba Energy
Project (Phase I)
4,000-4,400
(8.9-9.8)
6,500
(14.5)
3,700
(8.2)
5,000
(11.1)
Mesaba Generating
Station (Phases I & II)
8,800-10,300
(19.6-22.9)
15,200
(33.9)
7,400
(16.5)
10,000
(22.3)
a
To meet water quality criteria, the cycles of concentration in the cooling tower at the West Range Site must be reduced from 5
for Phase I to 3 for Phases I & II, which results in a greater than doubling of water requirements.
b
gpm – gallons per minute; cfs – cubic feet per second
The maximum process water requirement would be dependent upon many factors including, but not
limited to, the cycles of concentration in the cooling towers, fuel consumed, ambient conditions, extent to
which cooling tower blowdown is treated to remove total dissolved solids, chemistry of the receiving
waters, and water quality criteria standards applied to those waters. The cycles of concentration in the
cooling towers would be dependent upon source water chemistry, specifically the concentrations of
mercury, total dissolved solids; and hardness. In general, if the source water is relatively low in total
dissolved solids the cycles of concentration in the Mesaba Generating Station’s cooling towers could be
increased, resulting in lower make-up rates.
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Abandoned mine pits would be the primary source of water at either the West Range Site or the East
Range Site. A water pipeline and pumping system would convey water from the abandoned mine pits to
the Mesaba Generating Station. Water from the water pipeline would be filtered prior to use in the Mesaba
Generating Station. Sludge from the raw water treatment process would be taken to a local non-hazardous
landfill for disposal.
2.2.2.4
Infrastructure Requirements
The project’s generating facilities would connect to the power grid via new and existing HVTL
corridors to substations located near the unincorporated communities of Blackberry (West Range Site) or
Forbes (East Range Site). The HVTL infrastructure would need to be reconstructed and/or reinforced
under the Proposed Action for either the West Range Site or the East Range Site as described in Section
2.3.
Electric power would be produced in two CTGs (about 220 MW each) and in one STG (up to 300
MW). The electrical output of the CTG and STG at 16.5-kV and 18-kV, respectively, would be below the
level needed for electrical transmission to the grid; hence, transformation to the appropriate voltage would
occur prior to the Mesaba Generating Station’s switchyard. Excelsior’s design and cost for the power plant
have been based on such transformation delivering electric power to the switchyard at a voltage of 230-kV.
Based on a nominal net electric output of 606 MW at a 0.90 power factor, one bundled conductor 230kV transmission line rated at 1,585 Amperes would be sufficient to carry the peak electrical output of either
plant phase. A single 345-kV bundled conductor rated at 2,113 Amperes could carry the full 1,212
MWe(net) output from both phases. However, a single transmission line interconnecting the plant to the
point of interconnection (POI) would not meet the single failure (n-1) criterion and would result in a total
loss of output from the plant in the event of a forced line outage or when line maintenance is required.
Therefore, a minimum of three 230-kV HVTLs, two 345-kV HVTLs, or a combination of two 230-kV
HVTLs and one 345-kV HVTL would be required to satisfy the single failure criterion design element.
The choice of transforming voltage level for the Mesaba Energy Project between 230 and 345-kV is
not solely dependent on the plant site and length of transmission lines. This choice is also dependent on
the voltage levels at which the substation currently operates as well as existing “downstream” power flow
constraints. Presently, there is no 345-kV voltage transmission infrastructure at either the Blackberry
Substation or the Forbes Substation. Efforts to bolster Minnesota Power’s (MP) ability to exchange power
between regions with fewer attendant losses would dictate that new transmission developments in the
region operate at higher voltages. Excelsior believes that 345-kV would be the future standard on which
such transmission developments on the Iron Range will be focused and has based its decision for the
interconnection voltage on that premise. The results of the Midwest Independent System Operator’s
(MISO) Interconnection Studies will confirm whether Excelsior’s decision regarding the likelihood of
future 345-kV development at the two substations is appropriate.
Based upon the results of studies completed to date, MISO has determined that the output of Mesaba
Phase I would be fully deliverable within the MISO footprint. For the West Range Site, network upgrades
consisting of an additional 230-kV HVTL between the Boswell Substation and the Riverton Substation
would be required; however, no such upgrades would be required for the East Range Site. Excelsior has
requested that MISO conduct sensitivity analyses to examine whether successful development of the
Minnesota Steel project (initially assuming a 300 MW load) would eliminate the need for the additional
230-kV HVTL at the West Range Site. These sensitivity analyses are currently underway. MISO studies
are also underway to identify network upgrades required to ensure that Mesaba Phase II would be
deliverable within the MISO footprint at the West Range Site. Based upon the results of Excelsior’s
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preliminary studies, some existing transfer capability would be available to deliver the Phase II output;
however, it is likely that additional 230-kV and/or 345-kV network upgrades would be required at either
site for Mesaba Phase II to resolve local injection issues and ensure full power deliverability to the Twin
Cities. As in the case for Mesaba Phase I, for purposes of evaluating the network upgrades required for
Mesaba Phase II at the West Range Site, Excelsior has requested that MISO perform sensitivity analyses
assuming the successful development of Minnesota Steel but operating at two levels of power demand, 300
MW and 500 MW. The results of the MISO studies are expected to be available later this year.
Because of the pending MISO decisions affecting the interconnection voltage for Phases I and II,
Excelsior has requested an HVTL Route Permit that allows flexibility to change its West Range Site
interconnection voltage plans. The use of 345-kV at the East Range Site is dictated by the increased power
losses that would otherwise occur if the system were operated at 230-kV. Section 2.3 summarizes
Excelsior’s plans to deal with uncertainties related to MISO’s ongoing studies and pending decisions.
Easements across public and private lands would be required to provide HVTLs, pipelines, rail, and
highway access to the Mesaba Generating Station. Two HVTL corridors traverse the West Range Site and
one HVTL corridor traverses the East Range Site. Easements would also be required for infrastructure
associated with the Phase I and Phase II developments, construction of such infrastructure, and operation
of the Mesaba Generating Station. Water pipelines would require access from RGGS Land & Minerals,
LTD., L.P. (RGGS) for the West Range Site, and from Cliffs-Erie, LLC (CE) and the USDA Forest
Services for the East Range Site.
Potable water demand would be generated by construction and operational personnel. Approximately
30 gallons per day per person would be required. During construction peak water demand would be
45,000 gallons per day based on 1,500 construction workers. Once operational, water demand would
decrease to 7,500 gallons per day based on 250 workers on site. Use of city water would be anticipated,
although on-site treatment of water from abandoned mine pits through filtration and clarification could also
be performed to meet potable water standards.
2.2.2.5
Transportation Requirements
Coal and other materials would be delivered to the Mesaba Generating Station primarily by rail, with
some materials delivered by truck. The BNSF Railway (BNSF) and the Canadian National Railroad (CN)
are the two principal rail providers in the region. Rail loop access to either site would be required, and
potential rail alignments are described in Section 2.3. The plans for connecting the BNSF and/or CN with
the Mesaba Generating Station on the West or East Range Sites would require plan approvals from the
respective companies; however, no other public approvals would be needed.
Rail cars arriving via unit trains would be unloaded using a state-of-the-art rapid discharge rotary
dumper with an automatic railcar positioning system. The rail loop and system would allow a full-length
8,000-foot long coal train (i.e., 135-car unit train) to be pulled through the site without uncoupling any of
the cars. Each rail car would be rotated upside down inside the rotary dumper building to unload the coal
contained therein. The dumper building would be enclosed and maintained under negative pressure during
the unloading process to minimize fugitive emissions. Each unit train would take approximately three to
four hours to unload.
Other incoming materials delivered via rail could include petroleum coke, flux, and construction
materials and equipment. Construction deliveries would require two trains per week. Depending upon the
fuel being used, Phase I would produce between 500 and 800 tons per day of slag, which is a black, nonhazardous, glass-like material that has broad industrial uses. Also, depending upon the fuel being used,
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2. PROPOSED ACTION AND ALTERNATIVES
approximately 30 to 160 tons per day of elemental sulfur would be produced that would be sold and
transported off site. Sulfur would be transported off site by rail. Excelsior expects that slag would be sold
to local markets and transported off site by truck; however, the project would provide the capability to load
slag onto rail cars for transport to more distant markets depending upon economics.
An access road would also be required at either site for the plant. Roadway access would be required
for personnel and for deliveries by truck during construction and operation of the plant. Potential access
road alignments for the West Range and East Range Sites are described in Section 2.3.
2.2.2.6
Land Area Requirements
The Phase I site layout would encompass approximately 100 acres. An additional 80 acres of land
would be required for a temporary construction staging and laydown area for the Phase I equipment and
5 acres for a concrete batch plant. Since Phase II would be similar to Phase I with respect to its balance of
plant equipment, a total of approximately 200 acres would be required for Phases I and II, excluding
construction staging and laydown areas. Phase I would use the footprint reserved for Phase II as the
construction staging and laydown area; however, an additional 85 acres of land would be used onsite for a
construction and laydown area during Phase II. On-site rail alignments, access roads, and utility corridors
would also affect the amount of acreage required for project components. The balance of land area on the
West or East Range Site would remain wooded to the extent practicable to maintain a buffer area (for
visual screening and noise reduction) between the power plant footprint and surrounding land uses. The
site layout plans would be developed so as to reduce the extent of impact on environmental resources as
practicable within design constraints for the generating station components.
Construction of the proposed rail line to accommodate Phase I and Phase II would require additional
off-site ROWs to be obtained. The proposed ROW would be 100 feet wide with additional width needed
in some of the cuts or fill sections. The track work would begin immediately after construction approval
was received to allow for delivery of construction materials. Rail line construction would require
approximately 15 months.
The rail line would be constructed on a 32-foot wide prepared roadbed within the 100-foot wide rightof-way. Permanent or temporary easements may be required in some areas. The side slopes would be 1:3
with a 5-foot wide flat bottom ditch for drainage. The prepared roadbed would have the track offset to one
side of centerline to allow for a 12-foot railroad inspection road alongside. The coal unloading process
would require the final track elevation to be level; therefore, the approach grades would be limited to 0.3
percent. The grading and track work would conform to the American Railway Engineering and
Maintenance of Way Association (AREMA) standards.
Storage requirements for the major process feedstocks and byproducts are shown in Table 2.2-4. The
volumes of material storage requirements are for each phase; total storage for both phases would be double
the amounts shown.
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DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Table 2.2-4. Feedstock and Byproduct Storage Requirements for Each Phase
Material
Storage Requirements
385,000 tons (20/25 days active/inactive storage based on maximum PRB-1
coal usage);
Coal Pile
Dust control; Water runoff control
Pet Coke Pile (Storage would be
subset of total coal storage)
105,000 tons (20/25 days active/inactive storage);
Flux Silo
4,660 tons (20 days active storage)
Sulfur Tanks
Max 162 tons/day generated, based on Illinois No.6 coal (7 days on-site
storage; 30 rail cars parked on site)
Slag Pile
34,800 tons (45 day storage, wet basis, using PRB2:PRB3 coal blend)
2.2.3
Dust control; Water runoff control
Discharges, Wastes, and Products (Outputs)
2.2.3.1
Air Emissions
Air emissions by the Mesaba Generating Station would be largely independent of the project site. The
block flow diagram in Figure 2.2-1 shows air emission sources and their associated control equipment for
the Mesaba Energy Project (Phase I); the Phase II plant would be identical. Refer to Table 2.1-1 for
estimated air emissions. Excelsior’s design team estimated the maximum and average emission quantities
from each emission point using:
•
•
•
•
•
Equipment supplier data;
Best available control technology (BACT) as proposed for the Mesaba Generating Station in the
New Source Review Construction Authorization Permit (Air Permit application);
Test results for similar equipment at other IGCC facilities, especially the existing Wabash River
IGCC plant (which also uses E-Gas™ gasification technology);
Engineering calculations, experience, and professional judgment; and
Published and accepted average emission factors, such as the EPA Compilation of Air Pollutant
Emission Factors (AP-42).
Criteria Pollutants
Emissions of criteria pollutants would occur from the operation of the combustion turbines; TVBs;
flares; auxiliary boilers; cooling towers; fugitive emissions from handling, preparation, and storage of
coal/coke and slag during the operational phase; and emergency generators and emergency fire and water
pump engines. Transportation-related emissions would be low in comparison to the emissions from plant
operations.
Carbon Dioxide Emissions
The amount of CO2 emitted by the power plant would vary depending on the feedstock, as indicated in
Table 2.1-1, and the net heat rate. The project proponent has estimated that the Mesaba Generating Station
would emit approximately 10.6 million tons of CO2 per year using mainly sub-bituminous coal. CO2
emissions from power plants are not currently regulated under the Clean Air Act, and there are no
economic incentives in place to encourage reductions in the emission of this greenhouse gas. However, as
described in the Potential Carbon Capture Retrofit subsection of Section 2.2.1.3, the plant would be
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DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
designed to allow for future modification to add CO2 capture technology, and the project proponent has
performed a preliminary study of the potential geologic sequestration of CO2 emissions from the plant.
Combustion Turbine Generators
The production of syngas at relatively high pressure allows efficient and cost-effective syngas cleanup
prior to combustion in the CTGs to produce electricity. Air emissions would be controlled using the
following treatment steps applied to the syngas:
•
•
•
•
•
Hot gas particulate matter filtration via cyclone and ceramic filter to achieve more than 99.9
percent removal of particulate matter;
Water scrubbing to remove soluble contaminants, condensable materials, and suspended
particulate matter;
Amine treatment combined with COS hydrolysis;
Carbon adsorption for removal of mercury and other trace contaminants; and
Moisturization (water saturation) for NOx control and improved power production.
In addition to the syngas treatment, the moisturized product syngas fuel would be diluted
approximately 100 percent (1:1) with ASU nitrogen for additional NOx reduction. Steam injection, in lieu
of nitrogen dilution and moisturization, would be used for NOx control when operating on natural gas.
Finally, each CTG would be equipped with inlet air filters to minimize particulate matter emissions
potentially caused by advection of suspended atmospheric materials contained in the combustion air.
Emissions from the CTGs are based on the following gas concentrations as emitted at the HRSG stack
(or, in the case of particulate matter, the stack emission rate):
Syngas
•
•
•
•
•
SO2, based on 50 parts per million, volumetric dry (ppmvd) as H2S in the undiluted syngas, rolling
30-day average and assuming 100 percent conversion of H2S to SO2
NOx, 15 ppmvd (at 15 percent O2)
CO, 15 ppmvd (at 15 percent O2)
PM10, 25 lb/hr/CTG
Volatile Organic Compounds (VOC), 2.4 ppmvd (at 15 percent O2)
Natural Gas
•
•
•
SO2, pipeline-quality natural gas (assumed 1.0 grain/100 standard cubic feet (scf) total sulfur) and
assuming 100 percent conversion of sulfur to SO2
NOx, 25 ppmvd (at 15 percent O2)
Other criteria pollutants, equal to or less than syngas emission rates
Tank Vent Boilers
Two TVBs, one for each phase, would be designed to safely and efficiently dispose of recovered
process vapors from various process tanks and vessels associated with the gasification process. The TVBs
would prevent the atmospheric emission of reduced sulfur compounds and other gaseous constituents to
the atmosphere that could cause nuisance odors and other undesirable environmental consequences. The
TVBs may also be operated on natural gas to produce steam for the Mesaba Generating Station during
gasifier shutdowns.
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DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Flares
The elevated flares for each phase would be designed for a minimum 99 percent destruction efficiency
for CO and H2S. The flares would normally be used only to oxidize treated syngas and natural gas
combustion products during gasifier startup operations. The flares would also be available to safely
dispose of emergency releases from the Mesaba Generating Station during unplanned upset events.
Fugitive Emissions
Fugitive emissions are those emissions not caught by a capture system, and that are often due to
equipment leaks, evaporative processes, or wind. Such fugitive emissions for the proposed IGCC facility
would likely occur, based on normal equipment leakage, and were estimated using standard U.S. EPA
fugitive emissions factors for valve seals, pump and compressor seals, pressure relief valves, flanges, and
similar equipment.
Material Handling Systems
Fugitive particulate matter emissions (fugitive dust) would be generated by coal/coke and slag
handling, preparation, and storage during the operation of the Mesaba Generating Station. Sources of
these emissions would include the active and inactive coal/coke storage piles, conveyors/transfer points,
slurry preparation area, and the slag storage area. Estimated fugitive emissions are provided in Section 4.3,
Air Quality and Climate.
Wet spray dust-suppression systems would be employed at various points in the coal handling and
storage and coal slurry processes, which would require that water be supplied to the various injection
points. This water could be blended with glycol for freeze point suppression, and/or surfactants (wetting
agents) or chemical binding or encrusting agents. Because of the glycol addition, any free water draining
from the solids would be captured and treated as required before re-use on-site or disposal off site.
Fugitive dust would be generated from in-plant trucks hauling slag from the gasifier slag handling area
to the slag storage pile or bins to await shipment by rail or truck to offsite users. Watering of the roadway
near the pile to suppress dust and periodic removal/cleanup of dust-producing material would minimize
potential emissions from this source.
Cooling Tower Drift
Particulate emissions would also occur from the cooling towers as a result of drift. The total dissolved
solids (TDS) content of the drift is the maximum value estimated from water quality measurement data for
the makeup water.
The high concentration of TDS found in process water from mine pits at the East Range Site would be
the source of increased PM10 emissions from the East Range Site cooling towers relative to such emissions
from the West Range Site. TDS in process waters for the East Range Site have been shown to be present at
concentrations up to 1,800 milligrams per liter, whereas peak concentrations of TDS in mine pits
associated with the West Range Site are on the order of 340 milligrams per liter.
Auxiliary Boilers
The auxiliary boilers would normally operate only when no steam would be available from the
gasifiers or HRSGs. The annual capacity factor for these boilers would be 25 percent or less. The
auxiliary boilers would include low-NOx burners for emission control.
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DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Emergency Diesel Engines
Diesel engines driving the emergency generators and fire protection pumps would be operated for
emergency purposes only and would not operate otherwise for more than 100 hours per year each. The
operation of these engines would be an additional although minor source of overall operational air
emissions.
2.2.3.2
Wastewater Effluents
Process Water Effluents
The allowable quantities and concentrations of chemical components in wastewater discharges from
the Mesaba Generating Station would be dependent in large part on the characteristics of potential
receiving waters. In the case of the West Range and East Range Sites, the receiving waters would be
located in different watershed basins that have substantially different water discharge standards. Therefore,
this section addresses the general aspects of plant effluents. The site-specific aspects of effluent discharges
are addressed for the respective plant locations in Section 2.3.
Although the amounts of water appropriated, consumed, and discharged would vary between the West
and East Range Sites, the general requirements for water would be as listed previously in Table 2.2-3. A
generalized water balance diagram that applies to both potential sites is shown in Figure 2.2-10.
Wastewater generated from gasification and slag processing operations containing levels of heavy
metals and other contaminants from the feedstocks would be treated in a ZLD system. This system would
recover distilled water for reuse in the power plant, thereby reducing fresh water consumption, and it
would concentrate heavy metals and other contaminants of concern into a solid waste stream. The solid
waste, which is likely to be classified as a hazardous waste, would be disposed of at offsite waste
management facilities; therefore, no wastewater streams from the ZLD system serving the gasification
island would require disposal at either site.
At the West Range Site, the process wastewater discharge would primarily be generated from the
removal of portions of condenser cooling water (cooling tower blowdown) as necessary to control
dissolved solids in the system. The constituents in the wastewater would essentially be the same materials
present from the water supply sources, but they would be more concentrated. The plant cooling towers
would be expected to operate approximately three to eight cycles of concentration (COC). Therefore, the
contaminants in the cooling water blowdown would be concentrated (due to evaporation in the cooling
tower) by about three to eight times the concentration in the water supply source. The Mesaba Generating
Station would operate at five COC during Phase I and at three COC for Phases I and II.
In addition to the cooling tower blowdown, process wastewater would be generated from other plant
systems, including HRSG blowdown, reject water from the boiler feed water demineralizers and treated
stormwater (i.e., processed through an oil/water separator) from plant drains isolated from contamination
by process solids/liquids.
Typical chemical additives would be introduced into the circulating water system to control cooling
water corrosion and fouling and to neutralize certain undesirable constituents in the plant discharge stream.
The majority of the chemicals would be consumed in the plant processes and only residual amounts would
be expected in the wastewater discharge. These residual amounts have been specified by Excelsior in its
Permit Application under the National Pollutant Discharge Elimination System (NPDES) permit and
would be regulated in the permit when issued.
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DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Figure 2.2-10. Water Balance Diagram Applicable to Phases I & II
Stormwater Management
Stormwater runoff from the plant site during operation of the Mesaba Generating Station would be
managed in three ways:
•
•
•
Stormwater with potential to become contaminated with process solids/liquids would be
segregated from process equipment by curbs, elevated drain funnels and other means and returned
as make-up to the feedstock slurry system or for other process water use.
Stormwater that could become contaminated with oil (such as water runoff from parking lots)
would be routed through an oil/water separator and then to the cooling tower blow down sump
prior to discharge off site.
Stormwater from other areas not associated with industrial activity would be routed to the
stormwater detention pond where settling could occur and initial rainfall (“first flush”) could be
contained, checked, and released in a controlled manner to a permitted outfall.
2-37
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Sanitary Wastewater
Alternatives for treating sanitary (domestic) wastewater produced by plant employees include
connecting to the local/regional publicly owned treatment works (POTW) or providing an onsite septic
system with leach field. Excelsior’s preferred alternative would be to discharge sanitary wastewater to a
local POTW.
Based on the number of personnel required for the operation of Phase I and Phase II (see Section
2.2.5), and using an estimate of 30 gallons per day generated per person, the expected sanitary wastewater
discharge would total approximately 3,300 gallons per day for Phase I and 5,500 gallons per day for both
phases combined. These flows are based on the generating station having restrooms, locker rooms,
showers, and break room facilities. To accommodate flows when additional people would be on site
during tours, special maintenance activities, and outages, the capacity of the system would be based on
7,500 gallons per day of sanitary wastewater.
2.2.3.3
Solid Wastes
Solid wastes produced during plant operations would include spent catalyst materials (associated with
the COS hydrolysis and SRU systems), spent activated carbon beds associated with mercury removal
processes, spent activated carbon beds and char sludge associated with the sour water treatment system, the
solid waste stream produced by the ZLD system, commercial waste paper, and miscellaneous janitorial
streams.
The use of a ZLD process would prevent the discharge of heavy metals and other gasification wastes
with the plant wastewater effluent. The solid waste stream from this process, consisting mainly of
crystallized solids in a “filter cake,” would likely be classified as a hazardous waste due to metals content
and would be disposed in an approved hazardous waste landfill or other licensed facility.
Excelsior would manage operational wastes in accordance with applicable regulations, good industry
practices and established internal company procedures. Hazardous and non-hazardous wastes would be
properly collected, segregated, and recycled or disposed at approved waste management facilities within
regulatory time limits and in accordance with requirements. Plant staff would be adequately trained in
proper waste handling procedures. Waste manifests and other records and reporting would be maintained
as required by regulations and company procedures.
Typically, the ash content of coal would be in the range of 5 to 11 percent as received, and ash in
petroleum coke would average about 0.6 percent as received. However, the advanced features of E-Gas™
technology avoid two significant solid waste streams associated with some other types of coal-based power
generation: flue gas desulfurization (FGD) solids and ash. Removal of sulfur from IGCC syngas in a
relatively concentrated form and the subsequent production of elemental sulfur eliminate these significant
solid wastes. Slag production at full load would vary from about 500 tons per day up to a maximum of
about 800 tons per day per phase. Slag and elemental sulfur are considered to be potential revenueproducing streams that would be actively marketed by Excelsior.
2.2.3.4
Marketable Products
Although the primary product of the Mesaba Generating Station would be electric power, the plant
would also produce elemental sulfur and a glass-like, inert slag. A worldwide market exists for elemental
sulfur, although its value varies considerably with location, purity, and end use. The sulfur recovered from
the SRU would be stored in molten form and could be sold as a raw material for fertilizer and other
beneficial uses. No large-scale market exists for slag at this time; however, it is expected that slag can be
2-38
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
marketed for asphalt aggregate, construction backfill or landfill cover applications. Slag with a carbon
content of less than 5 percent by weight should be marketable as a higher value product such as roofing
shingle applications. There is also a potential to market the slag produced from petroleum coke gasification
for metals recovery.
The plant also would be designed to be retrofit for carbon-capture technology. Studies for Excelsior to
be undertaken as part of the Phase II Plains CO2 Partnership (one of seven regional partnerships funded by
the DOE Regional Carbon Sequestration Partnership Program) would produce a CO2 management plan
that would specify conditions required by potential purchasers of CO2. The carbon capture system may be
added after the generating station is in operation. For PRB coal, Excelsior would expect to capture
approximately one third of the carbon (as CO2) in the solid IGCC feedstock. This capture would come at a
reduction in capacity and an increase in heat rate.
2.2.3.5
Toxic and Hazardous Materials
Hazardous materials that would be used or stored for project operations include relatively small
quantities of petroleum products, liquid oxygen and nitrogen, molten sulfur, catalysts, flammable and
compressed gases, amine replacement and reclamation chemicals, water treatment chemicals, and minor
amounts of solvents and paints (Table 2.2-5). Materials and estimated quantities for the gasification/ASU
blocks were based on experience at the Wabash River plant.
Natural gas and syngas, which are flammable fuels, would be used in the Mesaba Generating Station,
specifically for the power block. Natural gas would be used as a startup or auxiliary fuel; it would be
utilized directly from the onsite pipeline (connecting to the off-site main pipeline) and would not be stored
on site. Syngas, which is a mixture of CO, H2, CO2, and water vapor, would be the primary fuel for the
combustion turbines generated on site and not stored. H2 would be used as a generator coolant. The H2
would be stored in pressurized gas tubes on a multi-tube trailer. The tube trailer would be stored outside
near the turbine-generators and would meet required building and fire codes. CO2 would be stored and
utilized for purging the generators after normal and emergency shutdowns.
Bulk quantities of liquid oxygen and nitrogen would be stored in tanks in the ASU to provide capacity
for startups and continued plant operation during short-duration ASU system outages. Other gases stored
and used at the facility would include those typically used for maintenance activities, such as shop
welding, and emission monitoring and laboratory instrument calibration. These gases would be stored in
approved standard-sized portable cylinders, and in appropriate locations.
Water treatment chemicals would be required and stored on site. Bulk chemicals, such as acids and
bases for pH control would require storage in appropriately designed tanks, with secondary containment
and monitoring. Gaseous chlorine (used/stored in compliance with all applicable regulatory requirements)
or hypochlorite bleach may be used for biological control of the various circulating and cooling tower
streams. Other water treatment chemicals would be required and used as biocides, pH control, dissolved
oxygen removal, and corrosion control for boiler feed water, cooling tower and cooling water treatment.
For raw water treatment, coagulants and polymers may also be used. Chemicals used for these purposes
are generally specified by the water treatment provider, and are available under a number of trade names.
Stored quantities of these materials would be small, ranging from 55-gallon drums to 500-gallon tanks.
2-39
Material
Quantity
(Phases I and II)
Form
General Location On-Site
Use
GASIFICATION/AIR SEPARATION UNIT AREAS
BULK CHEMICALS
Chlorine or Sodium Hypochlorite
Gas or Liquid
TBD*
Cooling Towers
Sodium Hydroxide
Liquid
60,000 gallons
Outdoors
Amine Reclamation and Sour Water
Treatment
Potassium Hydroxide
Liquid
2,000 gallons
Indoors
Dry Char Filter Cleaning
Water Treatment Chemicals
Liquid
Typically 55-gallon drums to
less than 500-gallon tank
Indoors
Pump Bldg, Slurry Prep Bldg,
Cooling Towers
Oxygen (95%)
Liquid
1,800 tons
Outdoors (Tanks)
ASU Backup Supply
Nitrogen
Liquid
5,000 tons
Outdoors (Tanks)
ASU Backup Supply
Molten sulfur
Liquid
200,000 gallons
Outdoors
By-product for Sale
Ammonium lignosulfonate
Liquid
TBD
Indoors
Slurry Prep Bldg for maintaining %
solids in slurry
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.2-5. Onsite Toxic and Hazardous Materials (Totals for Phase I and II)
MISCELLANEOUS/DISTRIBUTED MATERIALS
Liquid
Minimal
Indoors
Shop/Warehouse
Lubrication Grease/Oils
Solid/Liquid
Minimal
Indoors
Pump Bldg, Slurry Prep Bldg.,
Shop/Warehouse
Compressed Gases (Ar, He, H2)
Pressurized Gas Minimal
Indoors
Lab
Indoors
Lab
Chemical Reagents (acids/bases/standards) Liquid
Minimal
OTHER HAZARDOUS MATERIALS
Flammable/Toxic Gases (H2, CO, H2S, SO2)
Pressurized
Syngas Mixture
TBD
Outdoors
Process Piping/Vessels
Acetylene, Oxygen, other welding gases
Gas
Minimal (approved cylinders)
Indoors
Welding
Natural Gas
Gas (high
pressure)
Gas Pipeline
Supply piping only
Startup/Backup Fuel
2-40
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Paint/Thinners/etc.
Material
Diesel Fuel
Form
Liquid
Quantity
(Phases I and II)
2,000 gallons
General Location On-Site
Use
Outdoors
Emergency generator/fire water
pump fuel
POWER BLOCK AREA
Liquid
12,000 gallon aboveground
storage tank
Outdoors
Cooling water and BFW pH control;
battery acid
Sodium Hypochlorite
Liquid
20,000 gallon aboveground
storage tank
Outdoors
Cooling Tower biological control
Circulating Water Chemical Additives (e.g.,
Magnesium nitrate, magnesium chloride,
2-bromo-2-nitropropane-1,3-Diol,
5-chloro-2-Methyl-4-Isothizaoline-3-one)
Liquids
Typically 55-gallon drums to
less than 500-gallon tank
Indoors
Corrosion Inhibitor/ Biocides
Boiler Feedwater Chemicals (e.g., Carbonic
Dihydrazide, Morpholine, Cyclohexamine,
sodium sulfite)
Liquids
Typically 55-gallon drums to
less than 500-gallon tank
Indoors
Boiler feedwater pH/Corrosion/
Dissolved Oxygen/Biocide control
Mineral Insulating Oil
Liquid
30,000 gallons (estimated, to
be confirmed)
Indoors
Electrical Transformers
Lubricating Oil
Liquid
21,000 gallons (estimated, to
be confirmed)
Indoors
Combustion Turbine/Steam
Turbine/Misc. Equipment Lube Oils
Combustion turbine wash chemicals
Liquids
Intermittent use/Chemicals not
stored onsite/cleaning by
NA
contractor
Combustion Turbine Generator
cleaning
HRSG Cleaning Chemicals (e.g., HCl, Citric
acid, EDTA Chelant, Sodium Nitrite)
Liquids
Multiyear cleaning requirement/
Indoors
Temporary storage only
HRSG Chemical Cleaning
Carbon Dioxide
Pressurized Gas 50,000 standard cubic feet
Hydrogen
2-41
*TBD – to be determined
Pressurized
Gas
29,000 standard cubic feet
Outdoors
Outdoors (Assumes use of
multi-tube trailer. Active
volume based on 1 of 10
tubes per trailer)
Generator purging after normal and
emergency shut down
Generator cooling
(To be verified - Assumes use of
H2-cooled generators –
dependent on selected
manufacturer)
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Sulfuric Acid
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.2-5. Onsite Toxic and Hazardous Materials (Totals for Phase I and II)
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Diesel fuel would be used for the emergency generator and for the fire water pump. The expected
stored quantity (2000 gallons) was based on approximately eight hours of operation of the diesel generator
at full output (about 3 MW). This limited storage would require the plant to have contracts with fuel
providers specifying that deliveries of diesel fuel could be provided in less than 8 hours in the case of an
emergency. Appropriate containment and monitoring for spillage control would be provided.
Other petroleum-containing hazardous materials include the combustion and steam turbine lube oils,
steam turbine hydraulic fluid, transformer oils and miscellaneous plant equipment lube oils. These
materials would be delivered and stored in approved containers, stored in areas with appropriate secondary
containment, and would be used within curbed areas that only drain to internal drains connected to an oilwater separator system. Oil reservoirs, containment areas, and the separators would be checked regularly
to identify potential leaks and to initiate appropriate actions.
2.2.3.6
Pollution Prevention, Recycling, and Reuse
The Mesaba Generating Station would be designed to minimize process-related discharges to the
environment while demonstrating industrial technology in the use of coal for power generation. Table
2.2-6 lists the key pollution prevention, recycling, and reuse features that would be employed as part of
that plan.
Table 2.2-6. Key Pollution Prevention, Recycling and Reuse Features
Spill Prevention Control and
Countermeasure (SPCC) Plan
The SPCC Plan would develop measures to take in the event of a spill,
thereby insulating environmental media from the effect of accidental
releases. All aboveground chemical storage tanks would be lined or
paved, curbed/diked, and would have sufficient volume to meet all
regulatory requirements. A site drainage plan would also be developed
that would isolate routine, process-related operations from affecting the
surrounding environment.
Feed Material Handling
The coal storage area would be paved or lined so that runoff can be
collected, tested, and treated as necessary. The coal storage area has
facilities to control fugitive dust emissions. The coal conveyors would be
covered.
Coal Grinding and Slurry Preparation
The coal grinding equipment would be enclosed and any vents would be
routed to the tank vent incinerator/auxiliary boiler. The water used to
prepare the coal slurry would be stripped process condensate (recycled).
Gasification, High Temperature Heat
Recovery, Dry Char Removal and
Slag Grinding
The char produced in gasification would be removed and returned to the
first stage of the gasifier (recycled). This improves the carbon conversion
in the gasifier and reduces the amount of carbon contained in the gasifier
slag. Reduced carbon content makes the slag more marketable and
reduces the likelihood that it must be disposed in a landfill.
Slag Handling
The slag dewatering system would generate some flash gas that contains
H2S. The flash gas would be recycled back to the gasifier via the syngas
recycle compressor. Water that is entrained with the slag would be
collected and sent to the sour water stripper for recycling.
Sour Water System
Sour water would be collected from slag dewatering and the low
temperature heat recovery system, and the NH3 and H2S would be
stripped out and sent to the SRU. The stripped condensate would be
used to prepare coal slurry. Surplus stripped condensate would be sent to
the ZLD unit.
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DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Table 2.2-6. Key Pollution Prevention, Recycling and Reuse Features
Zero Liquid Discharge System*
The ZLD system would concentrate and evaporate the process
condensate. The ZLD system would produce high purity water for reuse
and a solid filter cake for disposal off site. The ZLD would concentrate
and dispose of heavy metals and other contaminants in the process
condensate. The ZLD would also be a recycle unit because the recovered
water would be reused, reducing the total plant water consumption.
COS Hydrolysis
The gasifier would produce small quantities of COS that cannot be
absorbed in the AGR system. The COS hydrolysis unit would convert
COS to H2S, which would then be removed in the AGR unit. The COS
hydrolysis unit would improve the sulfur recovery efficiency and reduce the
total amount of sulfur in the syngas, and ultimately, the release of SO2
from the HRSG stacks.
Mercury Removal Features
The mercury removal unit would use specially formulated activated carbon
to capture trace quantities of mercury that may remain in the syngas.
Mercury in the sour water handling system would be captured via
activated carbon filters strategically placed prior to potential release
points.
Acid Gas Removal
The AGR system would remove H2S from the raw syngas and produce a
sweet (low sulfur) syngas for use in the combined cycle power block. The
AGR would produce concentrated H2S feed for the SRU.
Sulfur Recovery Unit
The SRU would convert the H2S to elemental sulfur that would be
marketed for use as a fertilizer additive or for production of sulfuric acid.
The tail gas from the SRU would be recycled back to the gasifier.
Fuel Gas Moisturization
The fuel gas moisturization system would improve the recovery of low
level heat from the gasification process and serve as a diluent for the
syngas used in the combustion turbines. Nitrogen from the ASU would
also be used as a diluent. Dry, clean syngas typically has a heating value
in the range of 250 to 300 Btu per standard cubic foot. If the dry syngas
was used directly in the combustion turbines, the thermal NOx formed
would be too high. Earlier IGCC plants used steam injection for NOx
control, which is less efficient than using fuel moisturization and nitrogen.
Integration of the ASU and Power
Block
The ASU would produce nitrogen as a by-product; this is an effective
diluent for NOx control. The ASU would require large amounts of electrical
power for air compression. Part of the air compression requirements
would be provided by the combustion turbine compressors, further
integrating the gasification and combined cycle power block portions. This
integration reduces the ASU auxiliary power requirement and increases
the net power output by the plant.
Boiler Blowdown and Steam
Condensate Recovery
Boiler blowdown and steam condensate would be recovered from the
combined cycle power block and gasification facilities and would be
reused as cooling tower makeup.
Training and Leadership
All corporate and plant personnel would be trained on continuous
improvement in environmental performance especially as such training
and programs apply to: i) setting, measuring, evaluating and achieving
waste reduction goals and ii) reporting the results of such programs in
annual reports made available to the public.
*A ZLD system would treat water from the bottom of the ammonia stripper at either site to prevent contaminants in feedstocks from
being discharged to surface waters. For the East Range Site only, an enhanced ZLD system would also treat cooling tower
blowdown to eliminate all direct effluent discharges to receiving waters as necessitated by the stringent requirements applying to
discharges of mercury in the Lake Superior Basin watershed.
2-43
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
2.2.4
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Construction Plans
2.2.4.1
Construction Staging and Schedule
Under Excelsior’s proposed schedule, construction of Phase I would begin on the selected site early in
2008 and would be completed by 2011. Construction of Phase II would begin in 2010 and would be
operational by 2014. For Phase I start-up, system and feedstock testing, and long-term performance and
reliability demonstration of the project would require a minimum of one year (beginning in 2011), after
which the plant could continue in commercial operation.
Prior to construction, environmentally sensitive areas at the selected site would be identified and
flagged such that these areas would not be disturbed during site preparation activities. In accordance with
40 CFR Part 122.26(b)(14)(x), a Storm Water Pollution Prevention Plan (SWPPP) would be developed to
identify best management practices (BMPs) for erosion prevention and sedimentation control that would be
implemented during construction. The plan would include a description of construction activities and
address the following:
•
•
•
•
•
•
•
Potential for discharging sediment and/or other potential pollutants from the site;
Location and type of all temporary and permanent erosion prevention and sediment control BMPs
along with procedures to be used to establish additional temporary BMPs as necessary for the site
conditions during construction;
Site map with existing and final grades, including dividing lines and direction of flow for all pre
and post-construction stormwater runoff drainage areas located within the project limits. The site
map must also include impervious surfaces and soil types;
Locations of areas not to be disturbed;
Location of areas where construction would be phased to minimize duration of exposed soil areas.
Identify surface waters and wetlands either onsite or within one-half mile from the site boundaries,
which could be affected by stormwater runoff from the construction site, during or after
construction; and
Methods to be used for final stabilization of all exposed soil areas.
Initial site preparation activities would include building access roads, clearing brush and trees, leveling
and grading the site, bringing in necessary utilities, and undertaking dewatering activities that may be
required. Construction of temporary parking, offices, and material storage areas at this time would involve
the use of large earthmoving and logging equipment to clear and prepare the site for construction of the
plant. Trucks would be required to bring fill material for roadways and the plant, removing harvested
timber, removing debris from the site, and stockpiling fill material. Gravel and road base would be utilized
for the temporary roads, material storage, and parking areas.
The construction plan description generally would apply to both Phases I and II of the project. The
Phase II portion of the Mesaba Generating Station would be installed in the equipment staging and lay
down area utilized for Phase I construction. Therefore, a new Phase II staging and lay down area would be
identified and prepared at the beginning of the Phase II work, with the required permits and approvals
obtained prior to beginning the site preparation work. Detailed construction plans and specifications for
Phase II would include provisions necessary to protect construction and plant operating personnel and
equipment from potential impacts from the adjacent operating Phase I plant and to minimize operational
disruption during Phase II construction.
2-44
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
2.2.4.2
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Construction Materials
Construction material would be delivered to the site by truck and rail. A plant access road would be
developed for construction traffic. Completion of the rail spur at the start of construction activities would
allow plant equipment to be delivered by rail. An estimated 15 to 20 semi-trailer trucks daily would be
required to deliver material to the site. Construction deliveries by rail would likely require two trains per
week. The relatively small amounts of ballast required for construction of the rail loop would be obtained
from existing quarries that serve the BNSF and CN railway companies. The impacts of the small
incremental demand for ballast would not affect the production capacities of the quarries.
During construction, temporary utilities would be provided to support construction offices, worker
trailers, lay down areas and the construction areas. Temporary construction power would be provided by
the local utility company. Temporary generators could also be used until the temporary power system
would be completed. Area lighting would be provided and strategically located for safety and security.
Local telecommunication lines would be installed for phone and IT communications. Potable water bottles
would be provided for drinking water. Construction water would be supplied either by pumping and
treating surface waters in the vicinity or by connection to the local municipal water system.
2.2.4.3
Construction Wastes
Construction of the Mesaba Generating Station would generate certain amounts of wastes. The
predominant waste streams during construction would include site clearing vegetation, soils, and debris,
hydrostatic pressure-testing (hydrotest) water, used lube oils, surplus materials, and empty containers.
Surplus and waste materials would be recycled to the extent practical. If feasible, removed site
vegetation would be salvaged for pulp and paper production, or recycled for mulch. Construction water
use would be heaviest during the testing phase. Hydrotest water would be reused for subsequent pressure
tests if practical. Spent hydrotest water would be tested to determine if it exhibits hazardous
characteristics. If hazardous, the hydrotest water would be sent offsite for treatment; if non-hazardous, it
would be routed to the detention basin for discharge to local surface waters (in accordance with an NPDES
permit). Potential scrap and surplus materials and used lube oils would be recycled or reused to the
maximum practical extent. Temporary sanitation facilities would include portable toilets that would be
cleaned daily and the wastes hauled to a local disposal facility.
Although Excelsior would ultimately be responsible for the proper handling and disposal of
construction wastes, construction management, contractors, and their employees would be responsible for
minimizing the amount of waste produced by construction activities and would be expected to fully
cooperate with project procedures and regulatory requirements for waste minimization and proper
handling, storage, and disposal of hazardous and non-hazardous wastes. Each construction contractor
would be required to include waste management and waste minimization components in their overall
project health, safety, and environmental site plans. Typical construction waste management measures may
include:
•
•
Dedicated areas and a system for waste management and segregation of incompatible wastes.
Waste segregation should occur at time of generation;
A waste control plan detailing waste collection and removal from the site. The plan would identify
where waste of different categories would be collected in separate stockpiles, bins, etc., with
appropriate signage to clearly identify the category of waste;
2-45
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
•
•
•
•
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Hazardous wastes, as defined by the applicable regulations, would be stored separately from nonhazardous wastes (and other, non-compatible hazardous wastes) in accordance with applicable
regulations, project-specific requirements, and good waste management practices;
Periodic construction supervision inspection to verify that wastes are properly stored and covered
to prevent accidental spills and wastes from being blown away;
Appropriately labeled waste disposal containers; and
Good housekeeping procedures. Work areas would be left in a clean and orderly condition at the
end of each working day, with surplus materials and waste transferred to the waste management
area.
2.2.4.4
Construction Labor
The average number of construction personnel during Phase I (2008 through 2011) would be about
600, with as few as 50 and as many as 1,400 construction personnel onsite at any given time. It is
estimated that the on-site work force at the time of peak construction activities would be approximately
1,500 personnel, which would include Excelsior’s staff, consultants, and visitors in addition to
construction personnel. Excelsior expects that labor would be provided through the local Building Trades.
It is estimated that most of the construction activities would occur during a single shift between the
hours of 7:00 am and 5:30 pm, Monday through Saturday. Additional hours and/or a second shift may be
necessary to make up schedule deficiencies or to complete critical construction activities. During the warm
weather season, a second shift may be utilized to complete civil work activities. There would be X-ray
inspection, weld stress-relieving, and some production welding that typically occurs during a second shift.
The commissioning activities, prior to initial plant startup, would occur 24 hours per day.
2.2.4.5
Construction Safety Policies and Programs
Emergency services during construction would be coordinated with the local fire departments, police
departments, paramedics, and hospitals. A first aid office would be provided on site for minor first aid
incidents. Trained/certified Health Safety and Environmental personnel would be on site to respond and
coordinate emergencies. All temporary facilities would have fire extinguishers, and fire protection would
be provided in work areas where welding work would be performed.
The natural gas pipeline facilities would be designed, constructed, tested, and operated in accordance
with all applicable requirements included in the DOT regulations in Title 49 CFR Part 192 Transportation
of Natural and Other Gas by Pipeline: Minimum Federal Safety Standards; and other applicable Federal
and state regulations, including U.S. Department of Labor, Occupational Safety and Health Administration
(OSHA) requirements. These regulations are intended to ensure adequate protection for the public and to
prevent natural gas pipeline accidents and failures. Among other design standards, Part 192 specifies
pipeline material and qualification, minimum design requirements, and protection from internal, external,
and atmospheric corrosion.
2.2.5
2.2.5.1
Operational Plans
Operational Demonstration Test Plans
Excelsior would develop and submit an Operational Demonstration Test Plan to the DOE for review
and comment prior to plant startup. The plan would be intended to achieve the following objectives:
2-46
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
•
•
•
•
•
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Demonstrate mercury removal, activated carbon life expectancy, and operational costs in an IGCC
application;
Demonstrate smooth ramp-up to full capacity and greater than 90 percent annual availability with
the spare gasification train;
Demonstrate manifolding of gasification trains and operational swapping;
Demonstrate that phased refractory repair contributes to improved gasifier availability; and
Demonstrate the feedstock-flexible design.
2.2.5.2
Plant Demonstration and Operations
The plant demonstration would require approximately 12 months. Excelsior would implement the
Operational Demonstration Test Plan and document the results of the demonstration in relation to the
project objectives.
Following the demonstration phase, Mesaba Generating Station would be operated as a baseload
generation facility. The station would operate 24 hours per day except during scheduled outages for
maintenance. The facility would be designed for high reliability with multiple process trains. Although
the plant would include three gasification trains (from slurry preparation through dry char removal), only
two gasification trains would be required for full output (at 50 percent capacity each). The spare train
would normally be in standby service unless maintenance was being performed on one of the gasifier
trains. The Mesaba Generating Station would be designed to achieve an availability of greater than 90
percent during full operation.
The Mesaba Generating Station would be capable of “single train operation” where only one gasifier
and one combustion turbine would operate. The single train plant output would be somewhat below one
half of the full load output. Additional turndown would be possible by reducing the gasifier throughput in
either of the two trains or single train operation. Operation at reduced loads would be limited by physical
constraints, as well as the combustion turbine supplier’s emission guarantees, to about 70 percent of the
full load output.
The combustion turbine generators must be started on natural gas and loaded to a minimum level
before the fuel can be switched to syngas. The combustion turbine generators would be able to co-fire
natural gas and syngas within limits set by the combustion turbine manufacturer. The CTGs could also
operate on 100 percent natural gas. The power block would be designed to operate on 100 percent natural
gas when required, but at reduced capacity relative to operation on syngas.
2.2.5.3
Operational Labor
Operator hiring and training would begin about one year before the commencement of start-up.
Gasification area personnel would need extensive training in plant operations, reactive chemicals and
safety, industrial hygiene, and environmental compliance similar to that of operators in refineries and
chemical plants. Process simulators would be used as part of the training program. Generally, the staff
would consist of management and engineers, shift supervision and operations management, and shift
operating personnel. The operations staff would be integrated into the commissioning team so that they
would have hands-on experience with the plant when each system is operational after construction.
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DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
In addition to operations and management personnel, the Mesaba Generating Station would require
qualified staffing to support power production planning; equipment maintenance; procurement; laboratory
chemists and technicians; health, safety, and environmental specialists; administrative support;
benefits/human relations; and other necessary functions. The expected number of personnel during
operations is presented in Table 2.2-7.
Table 2.2-7. Estimated Operating Staff Required for the Mesaba Generating Station
System
Phase I
Staff
Phase II
Staff
Total Staff
(Phases I and II)
Gasification & ASU Subtotal
96
64
160
Combined Cycle Power Block Subtotal
11
11
22
Total Staff Requirement
107
75
182
2.2.5.4
Health & Safety Policies and Programs
Facility design features and management programs would be established to address hazardous
materials storage locations, emergency response procedures, employee training requirements, hazard
recognition, fire control procedures, hazard communications training, personal protection equipment
training and accidental release reporting requirements. Significance criteria would be determined on the
basis of Federal, state and local guidelines, and on performance standards and thresholds adopted by
responsible agencies.
Basic approaches to prevent spills to the environment include comprehensive containment and worker
safety programs. The comprehensive containment program would ensure that appropriate tanks, walls,
dikes, berms, curbs, etc. are sufficiently contained. Worker safety programs would be established to ensure
that workers are aware and knowledgeable about spill containment procedures and related health and
environmental protection policies.
The Minnesota Office of Pipeline Safety (MOPS) would have jurisdiction over the gas pipeline.
Pipeline facilities would be designed, operated and maintained in accordance with DOT Minimum Federal
Safety Standards in 49 CFR Part 192, which defines and specifies the minimum standards for operating
and maintaining pipeline facilities. The regulations require an Emergency Plan that would provide written
procedures to minimize hazards from a gas pipeline emergency. Key elements of any emergency plan
would include procedures for:
•
•
•
•
•
Receiving, identifying, and classifying emergency events such as gas leakage, fires, explosions,
and natural disasters;
Establishing and maintaining communications with local fire, police, and public officials and
coordinating emergency responses;
Making personnel, equipment, tools, and materials available at the scene of an emergency;
Proactive protection for people and insuring human safety from actual or potential hazards; and
Emergency shutdown of the system and safely restoring service.
The safety standards specified in Part 192 require each pipeline operator to:
•
Develop an emergency plan, working with local fire departments and other agencies, to identify
personnel to be contacted, equipment to be mobilized, and procedures to be followed in
responding to a hazardous condition caused by the pipeline or associated facilities;
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DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
•
•
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Establish and maintain a liaison with the appropriate fire, police, and public officials in order to
coordinate mutual assistance when responding to emergencies; and
Establish a continuing education program to enable customers, the public, government officials,
and those engaged in excavation activities to recognize a natural gas pipeline emergency and
report it to appropriate public officials.
Before placing the pipeline in service, a procedural manual for operation and maintenance of the
proposed pipeline would be prepared. The pipeline facilities would be operated and maintained in
compliance with MOPS regulations. The operator would become a member of the Gopher State
Excavators One-Call system that is utilized to prevent damage to underground pipelines by excavators and
others performing underground construction. Periodic aerial and ground inspections by pipeline personnel
would be conducted to identify dead vegetation, soil erosion, unauthorized encroachment or other
conditions that could result in a safety hazard or require preventative repairs or maintenance. In addition,
gas leak detection and cathodic protection surveys would be conducted periodically to ensure proper and
adequate corrosion protection and proper operation.
2.2.5.5
Worst-Case Operating Scenario
For development of its “worst case” operating scenario, parameters yielding maximum emissions were
identified. Operating conditions producing maximum emissions/discharges from the Mesaba Generating
Station are identified in Table 2.2-8, which assumes operation of the gasifiers under PSQ conditions and
considers known seasonal influences and the range of potential feedstocks for which the Mesaba IGCC
Generating Station would be designed to utilize. Pollutant emissions, discharges, and waste products
described in this chapter were quantified by Excelsior assuming the conservative PSQ conditions.
Table 2.2-8. Key Performance Indicators Used to Assess Worst Case Environmental Impacts or
Emissions of Mesaba Energy Project (Phase I, PSQ Mode)
Performance Parameter
CTG gross power, MW
Estimated
Range*
440
Comments
Total for two CTGs
STG gross power, MW
265 – 300
Varies depending on quantities of steam generated by
Gasification Island and HRSGs
Net plant generation, MW
580 – 606
Output from CTGs plus STG, less internal consumption and
losses
Coal/coke feed rate, tons/day (as
received)
5,300 – 8,550 Feed rate to gasifiers
Coal/coke feed energy, million Btu/hr
(HHV)
5,280 – 5,910 Energy content of gasifier feedstock
Product syngas energy, million Btu/hr
(HHV)
4,190 – 4,368 Energy content of syngas fuel delivered to CTGs
Coal conversion efficiency
Net overall heat rate, Btu/kW-hr (HHV)
Flux feed, tons/day
0.71 – 0.80
Fraction of solid feedstock energy in syngas feed to CTGs
8,900 – 9,500 Solid feedstock energy used per unit of net electricity to grid
0 – 250
Conditioning agent for gasifier feedstock
Slag by-product production, tons/day
500 – 800
Varies depending on feedstock composition and flux use
Sulfur by-product production, tons/day
30 – 165
Varies depending on feedstock composition
*emission or discharge range
Acronym: HHV – Higher Heating Value
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DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
PSQ would be achieved by increasing the slurry feed to the second stage of the gasifier to the point
where only slurry is used to quench the syngas, thereby eliminating the thermal loss associated with water
used to cool the syngas and increasing the overall efficiency of the plant. These efficiency gains would
translate into reduced feedstock use and, consequently, reduced pollutant emissions/discharges. However,
PSQ is an IGCC design improvement that is subject to further engineering and verification by experience
at Wabash River. Therefore, PSQ’s expected benefits have not been reflected in the maximum resource
requirements or maximum pollutant emissions/discharges quantified in this EIS.
2.3
DESCRIPTION OF ALTERNATIVE SITES AND CORRIDORS
This section describes the unique features of alternatives considered by Excelsior to implement the
Mesaba Generating Station at either the West or East Range Site, including potential plant sites and
respective alternatives for water sources and receiving waters, natural gas sources, rail and road
alignments, and HVTL corridors.
2.3.1
2.3.1.1
West Range Site and Corridors
Proposed IGCC Plant Site
The West Range Site, including the plant footprint and buffer land, is located within the city limits of
Taconite in Iron Range Township, Itasca County, Minnesota. The site is generally bounded by County
Road (CR) 7 to the west, a HTVL corridor to the north, and the Township boundary to the east (Figure
2.3-1). The site encompasses approximately 1,260 acres zoned by Itasca County for industrial use. Only
the northern-most 200 acres of the site are outside the Taconite city limits.
Two HVTL corridors traverse the buffer land, one in a north-south direction and a second in an eastwest direction. The HVTLs that occupy the north-south corridor are not currently in use. The closest
residential properties are located along CR 7, approximately 3,800 feet west of the proposed power plant
footprint, and on the north shore of Big Diamond Lake, approximately 3,850 feet to the southeast.
2-50
Existing Railroads
N
169
Iron Range
Township
PIT
Draft EIS
V EL
Mesaba Energy Project
G RA
Holman
Lake
RD
West Range Site
Plant Layout
Municipal Boundaries
Civil Township Boundaries
Potable Water
Gravity Sewer
HVTL Phase 2
T.
O LD
Little Diamond Lake
K
AR
Y
E
W DRIVE
HVTL Alt 1, 1A and Gas Alt 1 and 2
Proposed Blowdown, Sewer,
Potable and Process Water Lines
Gas Alt 3
Proposed Process Water Lines
Proposed Blow Down Alternatives
D
16
9
2,500
Itasca County - South
Coordinate System
0
SOUTH AVE.
ALICE AVE.
EKMAN AVE.
Greenway
Tow nship
Feet
5,000
West Range Plant Site
[Insert Figure 2.3-1. West Range EPlant
Site]
T HE L S T.
Gross -Marble Mine Pit
Greenway
Township
CHENEVERT AVE.
Figure 2.3-1
Twin Lakes
OL
Marble
Arcturus Mine
28
LINE
28 LINE
HVTL Alt 1, 1A and Gas Alt 1, 2 and 3
RA NG E EXPRE
SS WAY
Big Diamond Lake
VI
Geographic Names
Surface Water
Mine Pits
Streams
Existing Roads
S
TY H
WY
7
SP
G IB
Legend
H OD G I
BEASLEY
AVE.
COU
N
Dunning Lake
BA
National Energy Technology Lab
OLD HWY 7
Canisteo Mine Pit
RD
Figure 2.3-1. West Range Plant Site
U.S. Department of Energy
Col er aine
Taconite
RD
Bovey
Iron Range
Township
Island Lake
Little Reiley Lake
Reiley Lake
Shamrock Lake
Law r ence
Tow nship
Y7
HW
N TY
D
CO U
ER
HARRI ET ST.
K
LA
LY
N R E IL
RD
NELSON ST. SO.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
S
2-51
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
2.3.1.2
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Transportation Facilities
Existing Rail Lines in Vicinity of the West Range Site
The West Range Site is located approximately 1.5 miles north of the mainline tracks of the BNSF and
CN Railroads.
BNSF Rail Line
Rail shipments of coal from the PRB would be transported on the BNSF rail line across North Dakota
and then to Gunn and Taconite, Minnesota. Currently, about six trains per day travel along the BNSF rail
line from North Dakota to Gunn at speeds up to 25 miles per hour. From Gunn to the West Range Site
(approximately 12.5 miles) BNSF carried about 4 to 10 trains per day. This track is now closed because of
danger associated with pit wall collapse. Alternately, the BNSF rail line could be used from Brookston
northward to Kelly Lake and Keewatin westward to the West Range Site. This route would primarily be
used to transport materials other than coal to the West Range Site. Unit coal trains would only use this
route if there were a track problem east of Gunn; use of this route to transport coal from Powder River
Basin would increase the travel distance by 100 miles in each direction.
CN Rail Line
CN would deliver coal by way of the Superior, Wisconsin, area northward to Virginia, Minnesota, and
then west past Hibbing and Keewatin to Taconite/Bovey. CN unit coal trains would approach the West
Range Site from the east, travel past the site, and either back into the site or stop in Bovey, have the
locomotives disconnect and reconnect to the other end of the train, and access the site from the west. A
reverse move would be required for the empty train. Unit coal trains supplied by CN would use an
existing siding in Bovey that would need to be lengthened to accommodate this move. Delivery of other
materials to the plant would occur via the same type of movement, but with shorter trains.
A short span of existing CN track near the site is temporarily out of service because of the water
elevation in the Canisteo Mine Pit (CMP). Since the cessation of mining, the pit has filled with water and
affected the integrity of the CN track along the steep edge of the CMP near Bovey. CN has determined
that repairs to this line would not be appropriate without a solution to the rising water levels in the CMP.
Under common carrier regulations, the track would be required to be repaired and returned to service at the
request of BNSF or another shipper. Development of the West Range Site would lower water levels in the
pit allowing this section of the rail line to be redeveloped and returned to operation (Excelsior, 2006b).
Rail Access to the West Range Site
Coal could be delivered to the West Range Site by either BNSF or CN, which operate on a single track
located less than 2 miles from the West Range Site. Direct access to the site would be achieved by the
construction of short spurs from the mainline tracks onto the site boundary. Construction of 2 miles of new
track would be required between the existing mainline track and the boundary of the West Range Site; an
additional 4 miles of new track would be required for the portion of the rail loop within the site boundaries.
Three alternative rail access alignments were considered for the West Range Site, identified as
Alternatives 1A, 1B, and 2. The alternatives are shown in Figure 2.3-2 and described below. Table 2.3-1
provides a summary of each alternative.
2-52
Draft EIS
T.
7
O LD
169
Little Diamond Lake
ss
West Range Site
Plant Layout
Municipal Boundaries
Civil Township Boundaries
Iron Range
Tow nship
Holman Lake
Big Diamond Lake
A cc e
Y
E
W DRIVE
Proposed Roads
Proposed Rail Alt 1-A
Proposed Rail Alt 1-B
Proposed Rail Alt 2
VI
Mesaba Energy Project
S
TY H
WY
Ro
Dunning Lake
BA
Geographic Names
Surface Water
Mine Pits
Streams
Existing Roads
Existing Railroads
Legend
HOD G I
BEASLEY AVE.
Ta conit e
CO U
N
Ac
ce
ss
Iron Range
Tow nshi p
D
OL
16
SOUTH AVE.
ALICE AVE.
EKMAN AVE.
Marble
Greenway
Tow nship
IV E
DR
Mud Lake
Calumet
0
3,000
Itasca County - South
Coordinate System
Feet
6,000
West Range Rail and Road Alternatives
Figure 2.3-2
S
CHENEVERT AVE.
Twin Lakes
9
Arcturus Mine
Barbara Mine
Gross -Marble Mine Pit Hill Trumbull Mine
Greenway
Tow nship
Figure 2.3-2. West Range Rail and Road Alternatives
National Energy Technology Lab
OLD HWY 7
Canisteo Mine Pit
Bovey
RD
NS
U.S. Department of Energy
Coler ai ne
Little Reiley Lake
Island Lake
Y7
HW
N TY
CO
U
Reiley Lake
NELSON ST.SO.
HARRIET ST.
RD
L PIT
EX
RD
GE
AY
W
VE
GRA
SS
K
AR
PR
E
SP
GI B
RA
N
KE
COREY ST.
GARY ST.
Shamrock Lake
[Insert Figure 2.3-2. Rail and Road Access Alternatives, West R
KINNUN EN RD
ad
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Table 2.3-1. Rail Access Alternatives – West Range Site
Attribute
Alternative 1A
Alternative 1B
Alternative 2
Total length of track (miles)
6.0
6.9
4.5
Off-site length of track (feet)
15,900
19,000
9,000
10
10
10
0.30%
0.35%
0.40%
2 degrees
30 minutes
3 degrees
3 degrees
Train speed (mph)
Maximum grade
Maximum Curvature (loaded coal train)
Off-site right-of-way (acres)
35
43
20
Largest Cut (feet)
65
120
*
Largest Fill (feet)
25
25
*
Approximate Cut Qty (cubic yards)
3,000,000
8,500,000
*
Approximate Fill Qty (cubic yards)
2,000,000
2,000,000
*
Potential wetland impact (acres)
77
64
*
No. of residences within 1,000 feet
3
0
0
Closest residence (feet)
400
2,000
1,200
Alignment Meets Applicable Standards
Yes
Yes
No
Preferred
Alternative
Eliminated
Comments
Notes:*Was not computed because alignment was eliminated.
Rail Alignment Alternatives 1A and 1B
As shown in Figure 2.3-2, the common alignment for Alternatives 1A and 1B would divide from the
existing CN and BNSF main lines that run parallel to U.S. Highway (US) 169, generally following an old
railroad grade around the southern tip of Big Diamond Lake. East of the lake, Alternative 1A would turn
to the northwest between Big Diamond Lake and Dunning Lake to the proposed generating station. The
alignment for Alternative 1B would follow the same route east of Big Diamond Lake. But, instead of
diverting northwest between Big Diamond and Dunning Lakes, it would continue north on the east side of
Dunning Lake. Once north of the lake, it would bear west to the site. Both Alternatives 1A and 1B would
include a loop to the north of the proposed Mesaba Generating Station.
The alignments for Alternatives 1A and 1B would meet a Railroad Design Guideline developed by
Excelsior based on BNSF and CN unit train standards and could accommodate access by both rail service
providers. Acceptable curve radii require that the track alignment be directed east of Big Diamond Lake.
To provide an acceptable grade for Alternative 1A, track would require filling low areas located between
the two lakes and cutting from terrain obstacles approaching the plant site. To provide an acceptable grade
for Alternative 1B, construction would require cutting through a large tailing pile east of Big Diamond
Lake and through a large wetland area on the northeast corner of Dunning Lake; it would also require
significant additional contouring near the plant site. The rail loop for either alternative would be mostly on
a fill section.
Alternative 1A would be located within 400 feet of a residence on the north shore of Big Diamond
Lake and within 700 feet of a residence on the south shore of Dunning Lake. Alternative 1B would pass
within about 1,200 feet of the residence on Dunning Lake. Either Alternative 1A or 1B would require
construction of a bridge over the proposed new access roadway to the West Range Site to avoid public
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crossings that could cause traffic disruption near the Mesaba Generating Station. Existing forest roads
affected by the rail alignment could be re-routed to avoid traffic disruptions.
Excelsior identified Alternative 1A as the preferred alignment based on cost, better alignment of
curves, and lower anticipated environmental impacts. Alignment 1B would place the rail dumper building
in an area that would require coal to be conveyed across a greater distance to the Mesaba Generating
Station and would require significant earth removal work (as the route would cut across several large
tailing piles). The only practical benefit the alignment offers over Alternative 1A is that it would divert rail
traffic away from the several residential properties located on Big Diamond and Dunning Lakes.
Alternative 1A would require easements over, or acquisition of, some private property. Both alternatives
would have a surplus of cut/fill material that would require disposal.
Rail Alignment Alternative 2
Excelsior initially considered Alternative 2 for a rail alignment west of Big Diamond Lake (Figure 2.32). However, due to railway routing restrictions, BNSF would not be able to originate a shipment to the
site using the CN tracks. Instead, the origination point for the BNSF alignment would be west of the CN
rail spur. To maintain acceptable curvatures for this alignment in accordance with the Railroad Design
Guideline, based on BNSF standards, the origination point would require the alignment to be routed across
a portion of Big Diamond Lake. Excelsior determined that such an alignment would not be economically
or environmentally feasible and, therefore, eliminated it from further consideration.
Other Rail Alternatives Considered
Excelsior considered other rail alignments, including CN access from the west side of Big Diamond
Lake and BNSF access from the east side of Big Diamond Lake. These alternatives were eliminated from
further consideration because of the duplication of tracks, track alignments making it difficult to position
the coal dumper, topographic limitations on rail placement to avoid unacceptable curves, and the impact on
a larger area around Big Diamond Lake as compared to the other alternatives.
Roadway Access to the West Range Site
The West Range Site is located about 1.5 miles north of US 169, which is a two-lane east-west
highway locally, and about 0.25 mile to the east of Itasca CR 7, commonly referred to as “Scenic Highway
7,” which is a two-lane highway running mainly in a north-south direction. Other roadways include the
Cross-Range Heavy Haul Road, which is a gravel road used to allow heavy or slow loads to be transported
between mines across the Iron Range. The Cross-Range Heavy Haul Road also provides access to a cluster
of homes in the Big Diamond Lake/Dunning Lake area. The existing roadway system in the area of the
West Range Site is shown on Figure 2.3-2. Excelsior considered two access road components (Access
Road 1 and Access Road 2) to provide access to the West Range Site.
Proposed Access Road 1
The Itasca County engineer expressed the county’s interest in re-routing the alignment of CR 7 to
better serve local traffic patterns and the additional traffic related to the two large projects undergoing
environmental review (the Mesaba Energy Project and a Minnesota Steel Industries, LLC project designed
to produce sheet steel from taconite ore). The current intersection of CR 7 and US 169 has poor visibility,
relatively steep grades, and problems with slope stability. The realignment of CR 7 (Figure 2.3-2) would
serve as the primary access road (Access Road 1) to the Mesaba Generating Station, and would better
handle heavy equipment and increased traffic volumes resulting from construction activities tied to the two
projects. Itasca County would construct and own the realigned roadway, which would involve constructing
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a new two-lane roadway beginning at a new access point on US 169, approximately 7,000 feet east of the
existing CR 7 intersection. The new road would cross underneath the adjacent rail line, proceed north,
then curve west between Big Diamond and Dunning Lakes before terminating in its connection with
existing CR 7, just southwest of the West Range Site. The road would pass within a half mile of 22
residences, including 6 residences within 500 feet. The closest residence would be within 300 feet.
Itasca County would seek to move the CR 7 designation to the new roadway and include it as part of
the county’s state aid system. This would put all future maintenance of the road under the County’s
responsibility. The section of existing CR 7 between the plant and US 169 would remain in place as either
a lower level county road, or be turned over to the City of Taconite as a city street.
Proposed Access Road 2
Access Road 2 would provide access to the Mesaba Generating Station from Access Road 1 (the new
CR 7 alignment). If Access Road 1 were in place prior to construction of Phase I, all construction and
plant employee traffic would use it to access the plant site. However, based on the timing of Itasca
County’s construction of Access Road 1, it might be necessary for the plant to be served by an access road
from existing CR 7 (an extension of Access Road 2) until Access Road 1 was completed. If Access Road 1
were never constructed, special turning lanes onto CR 7 and US 169 would be required.
2.3.1.3
Water Sources and Discharges
Process Water Supply
For the West Range Site, the process water requirements would range from an annual average of 4,400
gallons per minute for Phase I to 10,300 gallons per minute for Phases I and II. The peak requirements
would range from 6,500 gallons per minute (Phase I) to 15,200 gallons per minute (Phases I and II).
Excelsior considered three alternatives for providing process water to the West Range Site, including the
use of nearby abandoned mine pits, the Mississippi River, and groundwater sources. Each alternative is
described below. Excelsior identified Alternative 1 (obtain water from nearby abandoned mine pits) as the
preferred alternative.
Process Water Alternative 1 (Obtain Water from Abandoned Mine Pits and Prairie River)
Alternative 1 (Excelsior’s preferred alternative) would involve pumping water from nearby abandoned
mine pits, including the CMP, the Lind Mine Pit (LMP), and the Hill Annex Mine Pit (HAMP) Complex
(Figure 2.3-3). The HAMP Complex includes the Arcturus, Gross-Marble, Hill-Trumble, and Hill Annex
Mine Pits. These pits currently are either filled with water and overflowing, are being pumped to avoid
flooding of important historical resources (the Hill Annex Mine State Park) due to rising water levels, or
are threatening to flood due to rising water levels. Both the CMP and the HAMP Complex could support
the water requirements for Phase I, while additional water resources from the LMP and possibly the Prairie
River would be sufficient to support Phase II. Excelsior proposes to withdraw water from the Prairie River
at a point downstream of the Prairie Lake Hydropower Facility, so water withdrawals would not impact
power production at the hydropower facility.
Routings for the pipelines would be located on public property adjacent to existing transportation
corridors wherever practicable. The pumps would be operated remotely from the Mesaba Generating
Station.
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2. PROPOSED ACTION AND ALTERNATIVES
Alternative 2 (Obtain Water from the Mississippi River)
For Alternative 2, water would be piped from the Mississippi River to the West Range Site. This
would require approximately 10 miles of pipeline and several pump stations, electrical facilities, support
structures, and land acquisitions. This alternative was not considered feasible due to the distance from the
river and the cost to construct and operate the necessary facilities.
Alternative 3 (Obtain Water from Groundwater Wells)
For Alternative 3, groundwater wells would be pumped to provide water to the site. Most wells in the
area produce only between 200 and 300 gallons per minute; therefore, this alternative would require the
development, operation and maintenance of up to 50 groundwater wells, pump stations, force mains,
electric services, and support structures to provide adequate flow for the Mesaba Generating Station. For
these reasons, Alternative 3 was not considered feasible and was eliminated from further consideration.
Process Wastewater Discharges
Process wastewater discharges would consist primarily of cooling tower blowdown blended with
relatively low-flow additional wastewater streams from other plant systems (including HRSG blowdown,
boiler feed water demineralizers and intermittent treated water from the oil/water separator serving the
plant drainage system). All other contact process water would be managed and treated in the ZLD system.
All sanitary wastewater would be treated separately. The projected peak and annual average process
wastewater discharge rates for the Mesaba Generating Station are summarized in Table 2.3-2. As described
in Section 2.2.3.2, nearly all of the wastewater discharged from the Mesaba Generating Station would be
condenser cooling water for control of dissolved solids (cooling tower blowdown). Hence, the constituents
in the discharge essentially would be the same as those in the water supply to the plant but more
concentrated.
Table 2.3-2. Estimated Wastewater Discharge Rates to Receiving Waters – West Range Site
Phase
Cycles of Concentration
Peak Discharge (gpm)
Average Annual Discharge (gpm)
I
5
1,300
550-900
I and II
3
5,140
2,200-3,500
The receiving waters for process water discharges from the West Range Site would be the CMP
(proposed Outfall 001) and Holman Lake (proposed Outfall 002) as shown in Figure 2.3-3. Wastewater
discharge rates to the CMP and Holman Lake would be inversely proportional to the cycles of
concentration at which the cooling towers would be operated. The number of cycles of concentration
operative in the Mesaba Generating Station would be determined by the concentration of mercury in the
CMP waters and the conditions of an NPDES permit for discharges to Holman and Panaca Lakes.
Excelsior expects that the Mesaba Generating Station would operate at five cycles of concentration during
Phase I and at three cycles of concentration during combined Phases I and II. A NPDES permit would
establish limits for parameters such as total concentration of mercury, TDS, and hardness.
Potable Water Supply
During construction, the Mesaba Generating Station would require a peak of 45,000 gallons per day of
potable water based on 1,500 personnel using 30 gallons of potable water per day each. After construction
of Phase I and II, the water demand will drop to about 7,500 gallons per day assuming 250 individuals on
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2. PROPOSED ACTION AND ALTERNATIVES
site year around. The annual usage for the facility during normal operation is estimated at approximately
2.7 million gallons. Two alternatives were considered to provide potable water to the West Range Site as
described below. Alternative 1 is Excelsior’s preferred alternative based on economic and permitting
considerations.
Alternative 1 (Obtain Potable Water from the City of Taconite)
The closest potable water source to the site is the City of Taconite. To provide potable water to the
West Range Site, an 8-inch diameter pipeline would be constructed from the Taconite system to the site as
shown in Figure 2.3-3. A booster station would be needed near the connection point to the city water
distribution system in order to provide the required water pressure for the Mesaba Generating Station. The
booster station would pump water from the Taconite system at a variable rate from 20 to 100 gallons per
minute. The wide pumping range would be required due to the fluctuations in water use that would occur
throughout the day at the facility.
Taconite is currently authorized via MNDNR Water Appropriation Permit No. 1976-2206 to withdraw
a total of 20 million gallons of groundwater per year to provide for its potable water needs. The most
recently published records from the MNDNR show that between 1988 and 2005, inclusive, Taconite’s
groundwater withdrawal rates varied between 11.3 and 17.3 million gallons per year. The Mesaba Energy
Project would require a peak usage rate of 16.5 million gallons per year during construction and average
roughly 2.7 million gallons per year of potable water during operations. This indicates that, at present, the
Taconite water supply system does not have sufficient capacity to supply potable water to the Mesaba
Energy Project during the construction phase and that the system will be close to full capacity once
operations of the Mesaba Energy Project begin.
In March 2007, the City of Taconite prepared and adopted a Water Management Plan (SEH, 2007) that
identified the improvements required to supply for the needs of the community and the Mesaba Energy
Project. These improvements include two additional groundwater wells, additional pumping facilities and
booster stations, along with future expansion of water storage facilities. If these system improvements are
completed by the time construction begins on the Mesaba Energy Project, there will be sufficient water
supply capacity, without impacting the existing firefighting and community needs. However, if these
improvements are not completed prior to construction, Excelsior would provide potable water to meet
construction workers’ needs by bringing in tanker trucks or through development of its own wells.
Alternative 2 (Construct On-Site Water Treatment Facility)
Alternative 2 would consist of constructing an on-site treatment facility with the capacity to treat 7,500
gallons per day of water from the CMP and HAMP Complex to provide potable water to the Mesaba
Generating Station. A micro-filtration system would be used to treat raw water pumped to the site from the
local mine pits at a rate of 10 gallons per minute to meet potable drinking water standards. This treatment
rate was determined based on a run time of approximately 12.5 hours to provide the daily water
requirement of the facility. Construction of a building to house the filtration system, a 5,000-gallon
underground reservoir, and pump would be required. The pump would supply the water from the reservoir
to the facility at the required flow rate and pressure. Excelsior would own the water treatment facility and
be responsible for the operation and maintenance of the facility.
The EPA classifies any facility that provides potable water to 25 or more of the same individuals every
day as a non-transient non-community public water supply system. Because the Mesaba Generating
Station would employ 182 permanent employees it would fall into that classification. Therefore, the
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2. PROPOSED ACTION AND ALTERNATIVES
treatment facility must be operated by a certified water operator and the treated water must meet all
standards of the Federal Safe Drinking Water Act and the Minnesota Department of Health (MDH).
During construction of the Mesaba Generating Station, potable water would not be available until the
process water features were completed. Therefore, potable water would be supplied to the site by other
means (e.g., tanker trucks) during construction.
Domestic Wastewater Treatment Alternatives
Excelsior considered two alternatives for treating and disposing of domestic wastewaters produced
during construction and operation of Phase I and Phase II. Alternative 1 would include the construction of
an onsite wastewater treatment plant. Alternative 2, preferred by Excelsior based on economic and
permitting considerations, would connect the Mesaba Generating Station to the Coleraine-Bovey-Taconite
wastewater treatment system via the Taconite pump station located approximately 2 miles south of the
West Range Site. The alternatives are illustrated in Figure 2.3-3.
Alternative 1 (Construct On-Site Wastewater Treatment System)
Alternative 1 would consist of constructing an onsite wastewater treatment facility using a stabilization
pond adjacent to the Mesaba Generating Station with a capacity to treat 45,000 gallons per day of domestic
wastewater (the maximum projected flow during construction). Once Phase I were operational, the
wastewater treatment facility would receive a maximum of 7,500 gallons of domestic wastewater per day
due to the reduced staff required to operate the station relative to that required during construction, and
part of the wastewater treatment facility would be closed in accordance with Minnesota Rules.
Treated effluent from the domestic wastewater treatment facility would be routed off-site either
through an 8-inch diameter gravity sewer to Little Diamond Lake or via the cooling tower blowdown
pipeline to Holman Lake (or CMP) approximately 1.4 miles south of the West Range Site. The facility
would require a NPDES permit to discharge treated domestic wastewater to Little Diamond Lake, Holman
Lake, or the CMP. A part-time on-site licensed operator would be required to monitor discharges and
ensure that the wastewater treatment facility meets the monitoring and discharge requirements specified in
the NPDES permit.
Alternative 2 (Connect to the Coleraine-Bovey-Taconite Wastewater Treatment Facility)
Alternative 2 would discharge domestic wastewater to the Coleraine-Bovey-Taconite wastewater
collection and treatment system, which receives wastewater from the three cities and discharges treated
effluent to the Swan River. The system has a design capacity of 499,000 gallons per day and received an
average flow of 334,000 gallons per day during the period from January 1 through May 31, 2005. During
the wettest 30-day period, the system received an average of 444,000 gallons per day with a peak day of
969,000 gallons per day.
Alternative 2 would consist of constructing approximately 10,000 feet of 12-inch gravity sewer, a
pump station, and 2,400 feet of force main from the West Range Site to the City of Taconite’s main pump
station located in the northeast corner of the city (Figure 2.3-3). The alternative would require a 50-foot
construction right-of-way and a permanent 30-foot ROW affecting approximately 14 acres and 8 acres,
respectively. The facilities would have the capacity to convey a maximum projected wastewater flow of
30,000 gallons per day during construction (7,500 gallons per day during generating station operations),
which is within the existing capacity of the Coleraine-Bovey-Taconite wastewater treatment facility.
2-59
Arbo
Tow nship
Draft EIS
Mine Pits
Streams
Existing Roads
Existing Railroads
Geographic Names
Surface Water
Legend
OLD HWY 7
HODGI N
ST
BEASLEY AVE.
Canisteo Mine Pit
West Range Site
Plant Layout
Municipal Boundaries
Civil Township Boundaries
Proposed Blowdown, Sewer,
Potable and Process Water Lines
RD
Mesaba Energy Project
A
Bov ey
Iron Range
Tow nshi p
3RD ST.
1ST ST.
RD
.
AY
Y
VI
E
W
DR I V
E
D
OL
Spring Lake
Loon Lake
9T
HA
VE
RD
Bass Lake
Mud Lake
W SWAN RI V ER RD
Greenway
Township
Twin Lakes
9
16
A
EKMAN AVE.
A VE.
CE SOUTH AVE.
LI
Marble
Arcturus Mine
Gross -Marble Mine Pit Hill Trumbull Mine
Barbara Mine
0
3,000
Itasca County - South
Coordinate System
Feet
6,000
West Range Water Sources
and Discharges
Figure 2.3-3
Foot Lake
Unorganized Territory of Little Sand Lake
Tow nship
Proposed Process Water Lines
Proposed Blow Down Alternatives
Potable Water
Gravity Sewer
Tr out Lak e
Tow nshi p
Iron Range
Township
Holman Lake
Little Diamond Lake
Big Diamond Lake
Dunning Lake
Gre enway
Township
Figure 2.3-3. West Range Water Sources and Discharges
National Energy Technology Lab
U.S. Department of Energy
LE Y
VE
Lakeview Cemetery
R
CU
RD
Buckeye Lake
Coler ai ne
Island Lake
BA
Jessie Mine
ARBO RD
Y7
HW
N TY
CO U
Shamrock Lake
TWIN LAKES RD
I rLittle
o n Reiley
R a n Lake
ge
Township
Taconite
Buckeye Two Tailings Basin and Dyke
GAYLEY AVE.
BA LL
ST .
Reiley Lake
RD
Grand R a pi ds
Tow nshi p
Greenway Mine
West Hill Mine
Lower Prairie Lake
Hill Mine Pit
Prairie Lake
Prairie River Dam
RD
D DR
IVE
BEN
PIT
0
RD
O AK
Dirty Mike Lake
POW ELL AVE.
P
EX
E
V EL
RA
NG
S
W
G RA
S
RD
K
AR
RE
S
SP
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Excelsior prefers Alternative 2 for treatment of domestic wastewater from the Mesaba Generating
Station because it would avoid the discharge of treated domestic effluent to public waters impaired for DO
and nutrients.
2.3.1.4
Natural Gas Facilities
Excelsior proposes to construct, own, and operate one 16-inch (or potentially 24-inch) diameter gas
pipeline to supply natural gas to the Mesaba Generating Station that would tap the two existing 36-inch
GLG pipelines approximately 12 miles due south of the West Range Site. Three potential natural gas
pipeline alternatives were initially considered by Excelsior to provide natural gas to the West Range Site as
indicated in The Table 2.3-3. Excelsior identified Alternative 1 as the preferred route (Figure 2.3-4) based
on economic factors.
On March 7, 2007, Nashwauk Public Utilities Commission submitted a permit application (PUC
Docket No. PL, E280/GP-06-1481) proposing to construct and operate a 24-inch diameter, high-pressure
natural gas pipeline between a take-off point on the existing 36-inch GLG pipelines in Blackberry
Township and a termination point near the City of Nashwauk. The new pipeline would follow essentially
the same alignment as proposed by Excelsior for its natural gas pipeline Alternative 1 between Blackberry
and Taconite near the West Range Site. From Taconite, the proposed pipeline would follow an additional
9-mile alignment to the City of Nashwauk. The commission indicated in its application that the proposed
pipeline would provide natural gas required to fuel the proposed Minnesota Steel facility and that the
Nashwauk Public Utilities Commission would be seeking other industrial customers in the future.
Therefore, the proposed gas pipeline would be sized to allow for industrial expansion near Nashwauk.
Excelsior has indicated that if this pipeline were approved by PUC and constructed in sufficient time as to
be available for use by the Mesaba Energy Project, Excelsior would enter into negotiations with the
Nashwauk Public Utilities Commission to purchase nature gas from the utility and would not construct a
separate natural gas pipeline for the power plant.
Table 2.3-3. Natural Gas Pipeline Alternative Routes – West Range Site
Attribute
Pipeline Length
Residential Dwellings
Water Crossings
Alternative 1
Alternative 2
Alternative 3
Existing Corridor
2.5 miles
10.5 miles
7 miles
New Corridor
10.7 miles
4.5 miles
5.5 miles
Within 300 ft
3
5
29
Stream
4
4
4
Lake
0
0
0
Both alternate routes, like the preferred route, would involve tapping the two existing 36-inch diameter
GLG pipelines. Unlike the preferred route, a pipeline developed along either of the other routes would be
licensed/permitted, constructed, owned and operated by NNG (as an interstate pipeline operator) rather
than Excelsior. Both alternate routes would originate approximately 9.4 miles southwest of the West
Range Site at the La Prairie tap and metering point located in La Prairie, Minnesota. Excelsior or the gas
pipeline owner would negotiate with landowners for easements to install the pipeline on each individual
tract that the route would cross.
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2.3.1.5
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
HVTL Corridors
Overview
As discussed in Section 2.2.2.4, power systems are designed according to the single failure (n-1)
criterion, which means that the power system must withstand the loss of a single line, generator,
transformer or bus bar without any severe disturbance of power supply. Excelsior applied for a HVTL
Route Permit including a combination of circuits and routes that would provide the necessary reliable
interconnection of Phases I and II to the power grid in accordance with the single failure criterion.
Point of Interconnection (POI)
The POI for the Mesaba Generating Station at the West Range Site would be the existing, 230/115-kV
Blackberry Substation owned and operated by MP and located approximately 8.5 miles south-southeast of
the West Range Site. The station is located at the intersection of CR 10 and CR 434 about equidistant
between the unincorporated community of Blackberry and the community of Marble. The Blackberry
Substation is the major HVTL hub in the area (Figure 2.3-4).
Alternative HVTL Routes to Support the West Range Site
As described in Section 2.2.2.4, Excelsior believes that 345-kV will be the future standard for
transmission developments on the Iron Range. Currently, however, there is no 345-kV transmission
infrastructure at the Blackberry Substation, and the likelihood of future 345-kV development at the station
is dependent on the results of MISO Interconnection Studies. Until such time as MISO confirms its
decision on the interconnection voltage for Phases I and II, Excelsior has requested an HVTL Route Permit
that would allow flexibility to change its West Range Site interconnection voltage plans. Excelsior’s Plan
A assumes the use of 345-kV circuits, while Plan B provides a contingency to allow the use of 230-kV
circuits. Both plans provide capacity for the Phases I and II combined output and allow for redundancy to
meet the single failure criterion. Accordingly, and in compliance with Minnesota Rules Chapter 4400,
Excelsior’s plans provide for preferred and alternative routes (that follow three potential alignments) as
described below and illustrated in Figure 2.3-4.
Plan A
Plan A would utilize two 345-kV HVTLs on a single steel pole structure (single ROW) from the
Mesaba Generating Station to the Blackberry Substation. This double-circuit 345-kV plan would
accommodate the full 1,212-MW output of Phases I and II while meeting the single failure criterion. Each
345-kV HVTL would have sufficient transfer capacity to carry the entire station electrical output, and both
lines would be installed during construction of Phase I. For Phase I, each of the two 345-kV HVTLs
would be operated at 230-kV, and either line would be capable of supporting the entire output of the plant
in the event of a contingency forcing one line out of service. Before Phase II would come on line, each of
the 345-kV HVTLs operating at 230-kV would be upgraded to its rated 345-kV capacity and thereafter be
capable of conveying the entire output capacity of the generating station to the substation. The necessary
upgrades would apply only to electrical substation equipment and involve no modification to the HVTL
structures or conductors installed to accommodate Phase I.
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NE 5TH ST
NW 4TH ST
W 16TH ST
0
Harris
Tow nship
SH
S
D
R R
R Y RD
NORBERG LANE
AR
G ra nd Ra pi ds
WYSS RD
Tow nshi p
S
A
W
RD
H
R
D
MAPLE DR W
Blackberry
D
R UCE DRIV E
Tr out Lak e
Tow nship
D R I VE
ELM
BIRCH DRIVE
Streams
Existing Roads
Existing Railroads
West Range Site
Mesaba Energy Project
Draft EIS
HVTL Alt 1A
HVTL Phase 2
Civil Township Boundaries
HVTL Alt 1
Mine Pits
RD
Greenway
Tow nship
Calumet
RD
RD
RD
KI NNU N E N
R
D
WE S
T BA
Y
DR
RD
RD
LY
HVTL Alt 1 and Gas Alt 1 and 2
Gas Alt 3
HVTL Alt 1, 1A and
Gas Alt 1, 2 and 3
HVTL Alt 1, 1A and Gas Alt 1 and 2
Gas Alt 1 and 2
Fe ele y
Tow nship
FE E
BLACKBERRY SUBSTATION
T
R
ES
TR
D
H AR T L A KE R D
R
PLUM RD
LK
ER
D
Goodland
Tow nshi p
D 65
Lone Pine
Tow nship
0
1
Itasca County - South
Coordinate System
Miles
2
West Range Natural Gas Pipeline
and HVTL Alternatives
Figure 2.3-4
FO
OL
Unor gani ze d Territ ory of Litt le Sa nd Lak e
Township
Gas Alt 1
Gas Alt 2
RD
National Energy Technology Lab
.
62
LI
NE
I
Plant Layout
Municipal Boundaries
VE
W SWAN RIVER RD
EA
5
D6
OL
Surface Water
Legend
IC
ST .
Iron Range
Tow nshi p
IN S
DO VE L ANET o w n s h i p
EAGLE RD BA
Iron Range
Township
Bovey
HOD
G
IC
AL
Marble
28
LINE
28 LINE
TWIN LAKES RD
7
TY H
WY
Ta conite
Coleraine
Y
D
Iron Range
Tow nship
VO
U.S. Department of Energy
BI
R
IX
RD
Cohasset
TE
RD
RD
NW 20 TH
ST
RD
RD
RD
POW ELL AVE.
Ar bo
Tow nshi p
R
A
PR
EX
E
ES
REAM RD
RD
SW 14TH AVE
RD
RI VE
A
NORWAY DRIVE
RD
RD
NG
JE
AK
C
RD
LA
N
RD
RD
AIRPORT RD
DS HW Y
DAVIS QD
OAK DRIVE
COU
N
RD
U
MISHE W
RD A
CT Y
O
SP
PIT
TWP RD B
V EL
S
0
NO RTHW OO
E ST SHO RE DRIVE
R
G RA
ES
RD
A RB
C
AC
6
3
L
IN
E
R
HEART LAKE ACCESS RD
W
Figure 2.3-4. West Range Natural Gas
Pipeline and HVTL Alternatives
RD
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
2-63
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Plan A provides for a preferred route (WRA-1, following alignment HVTL-1) and an alternative route
(WRA-1A, following alignment HVTL-1A) as illustrated in Figure 2.3-4. Both routes would share two
common segments (one existing and one new ROW), and each route would include two unique segments
(one existing ROW and one new ROW). The major difference between the routes is that WRA-1A would
run east of and parallel to Twin Lakes Road, while WRA-1 would run west of and parallel to Twin Lakes
Road. Both routes would avoid residences located on the road. Excelsior prefers WRA-1 because it would
have fewer water crossings, would cross fewer open fields, would avoid gravel mining operations, and
would generally be less visible. Both routes are similar in that they traverse areas that have a similar
residential density and are the shortest and most direct routes to the substation.
Plan A – Excelsior’s Preferred Route (WRA-1)
The preferred 345-kV double circuit HVTL route (WRA-1) would follow an alignment HVTL-1
including the following four segments:
(1) Approximately 1.6 miles of existing ROW shared with a MP 45 Line (45L) from the southern
boundary of the West Range Site south to the retired Greenway Substation located just south of US
169.
(2) Approximately 1.7 miles of new ROW from the retired Greenway Substation south and southeast
to a point near Twin Lakes.
(3) Approximately 4.6 miles of new ROW from the point near Twin Lakes south to the point of
intersection with MP’s 83L (230-kV) and 20L (115-kV) HVTL ROW.
(4) Approximately 1 mile of existing ROW shared with MP’s 83L and 20 Line 20L ROW east to the
interconnection with the Blackberry Substation.
The new alignment segments would require a ROW with a minimum width of approximately 92 feet;
however, Excelsior intends to acquire 100-foot ROWs (150-foot where natural gas pipeline and HVTL
would share routes), which would result in a total permanent ROW of approximately 134 acres. Existing
HVTL ROWs would not require widening of corridors. Approximately 66 residences would be located
within a half mile of the centerline of the preferred alignment, of which 17 would be located within a
quarter mile of the alignment. One residence would be located within 300 feet of the alignment and three
others would be located within 500 feet.
Plan A – Excelsior’s Alternative Route (WRA-1A)
Because route WRA-1 would require acquisition of about 6 miles of new ROW between the Greenway
Substation and the point of intersection with MP’s 83L and 20L HVTLs, Excelsior is required by
Minnesota Rules 4400.1150 Subpart 2.C to consider an alternative route.
The alternative route (WRA-1A) would follow alignment HVTL-1A and include the following four
segments:
(1) Same as first segment of WRA-1 (1.6 miles, existing ROW).
(2) Same as second segment of WRA-1 (1.7 miles, new ROW).
(3) Approximately 4.1 miles of new ROW from the point near Twin Lakes southeast then south to the
point of intersection with MP’s 62L (115-kV) HVTL ROW.
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DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
(4) Approximately 0.9 miles of existing ROW shared with MP’s 62L (115-kV) HVTL ROW south to
the interconnection with the Blackberry Substation.
The new alignment segments would require a ROW with a minimum width of approximately 92 feet.
However, Excelsior intends to acquire 100-foot ROWs (150-foot where natural gas pipeline and HVTL
would share routes), which would result in a total permanent ROW of approximately 121 acres. Existing
HVTL ROWs would not require widening of corridors. Approximately 62 residences would be located
within a half mile of the centerline of the preferred alignment, of which 21 would be located within a
quarter mile of the alignment. Two residences would be located within 300 feet of the alignment and five
others would be located within 500 feet.
Plan B
If MISO determines that the 345-kV transmission infrastructure is incompatible with regional
transmission planning initiatives, or if the timetable for building 345-kV transmission in the region would
not be acceptable, Excelsior would implement a 230-kV transmission contingency plan. Plan B would
begin by interconnecting the generating station to the POI with two 230-kV HVTL circuits mounted on a
single steel pole structure, which would accommodate the full 606-MW output of Phase I and meet the
single failure criterion. Although the double-circuit 230-kV HVTLs could accommodate the entire 1,212MW output of the combined Phases I and II, they would not meet the single failure criterion. Therefore,
Plan B would provide for an additional HVTL with the construction of Phase II. The routes considered
under Plan B are discussed in the four subsections below and shown in Figure 2.3-4.
Plan B, Phase I – Excelsior’s Preferred Route (WRB-1)
The preferred route for the double-circuit 230-kV HVTLs for Phase I of Plan B (WRB-1) would
follow alignment HVTL-1, the same as the preferred route WRA-1 of Plan A. However, the single-pole
HVTL structures required for 230-kV HVTLs would be shorter, ranging in height from 107 to 143 feet.
Approximately 10 structures would be 125 feet or taller. The new alignment segments would require a
ROW with a minimum width of approximately 73 feet. Existing HVTL ROWs would not require
widening of corridors.
Plan B, Phase I – Excelsior’s Alternative Route (WRB-1A)
The alternative route for the double-circuit 230-kV HVTLs for Phase I of Plan B (WRB-1A) would
follow alignment HVTL-1A, the same as the alternative route WRA-1A of Plan A.
Plan B, Phase II – Excelsior’s Preferred Route (WRB-2)
The preferred route for Phase II of Plan B would be the route not selected for the double-circuit 230kV HVTL in Phase I of Plan B. That is, if Excelsior’s route WRB-1 (alignment HVTL-1) were approved
for Phase I, route WRB-1A (alignment HVTL-1A) would be the preferred route for the single circuit 230kV HVTL for Phase II. Conversely, if WRB-1 were not approved as the preferred route for Phase I of Plan
B, it would be proposed as the preferred route for Phase II of Plan B.
The structures and new ROW requirements for the separate alignments would be comparable to those
described for WRB-1; however, the single-circuit 230-kV alignment would enable the use of shorter poles
(by approximately 20 feet). In the segments where the double-circuit 230-kV HVTL alignment would
coincide with the single-circuit 230-kV alignment, a minimum permanent ROW width of approximately
138 feet would be required for the parallel pole structures (affecting approximately 1.7 miles of new
2-65
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
ROW). The new alignments for Plan B, Phases I and II (including both routes) would require permanent
ROWs affecting approximately 255 acres. Existing HVTL ROWs would not require widening of
corridors.
Plan B, Phase II – Excelsior’s Alternative Route (WRB-2A)
Plan B would require an alternative route for the same reason as Plan A. The alternative route
proposed for Phase II of Plan B would combine segments from two existing HVTL corridors, one of which
traverses the northern section of the West Range Site. WRB-2A (alignment HVTL Phase 2 in Figure 2.34) would follow an alignment including portions of the ROWs for the MP 45L/28L and 62L/63L HVTLs.
Because the length of the HVTL for WRB-2A would be about 18 miles, Excelsior proposes to use HVTLs
rated at 345-kV on this route to avoid excessive line losses and elaborate switching requirements that
would be required for 230-kV. Both of the existing corridors are occupied by 115-kV HVTLs structures
owned by MP. Therefore, Excelsior proposes to use delta configuration 345-kV structures with an
underbuild feature that would carry the existing 115-kV HVTLs below the arms holding the 345-kV
conductors. The delta configuration structures would require a minimum permanent ROW width of
approximately 106 feet, which is generally within the parameters of the existing HTVL ROWs. Therefore,
the new alignments for Plan B, Phases I and II (including both routes) would require permanent ROWs
affecting approximately 134 acres. Approximately 214 residences are located within a half mile of the
ROWs that would be used for Alternative Alignment WRB-2A, 98 of which are located within a quarter
mile of the ROWs. Eight residences are located within 300 feet of the ROWs and 21 others are located
within 500 feet.
2.3.2
2.3.2.1
East Range Site and Corridors
Proposed IGCC Plant Site
The East Range Site, including the power plant footprint and buffer land, is located within the City of
Hoyt Lakes in St. Louis County, Minnesota (Figure 2.3-5). The site is generally bounded by CR 666 to the
east and a large mine tailings pile to the west. An existing 138-kV HVTL corridor leading to MP’s Laskin
Substation runs along the western boundary, and a rail line owned by a CN subsidiary runs along the east
and south sides of the property. The site encompasses approximately 810 acres of undeveloped property
owned by CE within the Superior National Forest and is zoned a mining district (MD) to support mining
operations that historically took place within the immediate vicinity of the site. The site has direct access
to CR 666 and includes a private, unpaved road used by CE to access its water pumping station on Colby
Lake. The closest residential properties are located along the southeast shore of Colby Lake,
approximately 1.2 miles south of the power plant footprint.
2.3.2.2
Transportation Facilities
Existing Rail Lines in the Vicinity of the East Range Site
One railroad, a subsidiary of CN, serves the area and could be used to transport coal and other
materials to the East Range Site. The nearest access to the BNSF Railway is at Hibbing, 40 miles from the
East Range Site. Therefore, the CN would be the only feasible near-term rail provider to the East Range
Site. The power plant footprint is located approximately one mile north and one mile west of two CN
railroad tracks. The east-west track runs from Eveleth, Minnesota, to Two Harbors, Minnesota. The northsouth track connects with the east-west track at Wyman Junction (about 1.7 miles southeast of the East
Range Site) and extends north to Embarrass, Minnesota.
2-66
Aurora
4th
Fore stry Rd
E 3rd Ave S
Aurora
2nd St E
Saint James Mine
S 1st St E
S Main St W
th ,
M is
Existing Railroads
Draft EIS
Rd
Wyand ott
6
666
Wyman Creek
Mesaba
Rail way
66
Wentworth Mine
Old Mesaba
CR 5 6
7R
d
Wyman
t 11
Allen
0
3,000
St. Louis County - Central
Coordinate System
Figure 2.3-5. East Range Plant Site
Feet
6,000
East Range Plant Site
Moose Mountain
Erie Mine Number Two Pit
Figure 2.3-5
res
5
Fo
Proposed Water and Sewer Lines
Proposed Process Water Lines
HVTL Alt 2
Shared HVTL Alt 1 and Alt 2
Gas Alt 1
HVTL Alt 1
e Rd Arling ton R
d
Hoyt Lakes
ty R d
Co un
Little Lake
Colby Lake
Civil Township Boundaries
Mesaba Energy Project
National Energy Technology Lab
Municipal Boundaries
Kennedy Memorial Dr
nt
y
sa be and Iron Range
Smolich Island
Du
lu
Mine Pits
Streams
Existing Roads
Legend
First Creek
Colby
East Range Site
Plant Layout
W 5th Ave S
Second Creek
Stephens Mine
Knox Mine
Geographic Names
Surface Water
U.S. Department of Energy
Forest Hill Cemetery
Stephens Creek
Donora Settling Basin and Dike
Little Mesaba Lake
White Township
W 3rd Ave S
4th St W
3rd St W
a
lro
S 3rd St W
Rd
Erie Mine Number One Pit
MP RR
y 135
State Hw
Rai
ve
dA
a ke
1st St W
yL
u
Co
Co lb
S
LTV
Mi
teel
nin g
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Figure 2.3-5. East Range Plant Site
2-67
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
The CN operates trains daily on the track serving Minnesota Power’s Syl Laskin Generating Station.
Coal would be delivered by other railroads to the CN at either Superior, Wisconsin, or at a rail yard south
of Eveleth, Minnesota. The CN rail line would be used to deliver coal to the site from Eveleth, and empty
trains would return by the same route.
Rail Access to the East Range Site
Excelsior considered two rail alternative alignments (Alternative 1 and Alternative 2) to connect the
East Range Site to the existing CN rail line. The alternatives are shown in Figure 2.3-6 and described
below. Table 2.3-4 provides a summary of each alternative.
Table 2.3-4. Rail Access Alternatives – East Range Site
Attribute
Alternative 1
Alternative 2
Total length of track (miles)
3.4
3.5
Off-site length of track (miles)
1.25
2.1
10
10
Train speed (mph)
Maximum grade
0.40%
0.40%
2 degree 30 minutes
3 degrees
Off-site right-of-way (acres)
15
26
Largest cut (feet)
50
50
Maximum Curvature (loaded coal train)
Largest fill (feet)
20
20
Approximate cut Qty (cubic yards)
2,300,000
2,100,000
Approximate fill Qty (cubic yards)
60,000
60,000
Potential wetland impact (acres)
59
18
No. of residences within 1,000 feet
0
0
Over 1,000 feet
Over 1,000 feet
Yes
Yes
Closest residence (feet)
Alignment Meets Applicable Standards
Rail Line Alternative 1
Alternative 1 would provide a traditional coal loop, which could accommodate a unit train that would
return in the same direction. The track would originate near MP’s Syl Laskin Generating Station rail spur
and travel east-northeast to the Mesaba Generating Station. The track would be about 17,800 feet long.
No residential dwellings are located near the proposed alignment.
Rail Line Alternative 2
Alternative 2 would accommodate a complete coal train, but it would cross the site (rather than looping
within it) and connect to the CN north-south track just north of Wyman Junction. This track would be
about 18,500 feet long with the rotary coal dumper near the midpoint. The track would depart the Syl
Laskin spur at an elevation of 1,455 feet, climb to an elevation of about 1,465 to 1,470 feet at the coal
dumper, and continue to climb to about 1,485 feet at the north-south CN track. To maintain a workable
grade, the track would need to cross under CR 666, which would require construction of a roadway bridge.
2-68
Draft EIS
Mesaba Energy Project
Existing Roads
Existing Railroads
Proposed Rail Alt 1-A
Proposed Rail Alt 2-A
Proposed Roads
6
National Energy Technology Lab
East Range Site
Plant Layout
Municipal Boundaries
Civil Township Boundaries
Rd
Wyman
11 7
Moose Mountain
0
1,500
St. Louis County - Central
Coordinate System
Feet
3,000
East Range Rail and Road Alternatives
Figure 2.3-6
est
Figure 2.3-6. East Range Rail and Road Alternatives
Geographic Names
Surface Water
Mine Pits
Streams
Legend
66
Wyman Creek
Fo r
]
U.S. Department of Energy
Rd
White Township
ty
n
Iro
Colby
C
n
ou
and
eR
Hoyt Lakes
h,
lut
Du
e
sab
Mis
ng
Ra
MP RR
Mesaba
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
ay
ailw
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DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
This alternative may have a lesser impact on wetlands; however, it would limit the choices for locating
the rotary coal dumper, and it would cause trains to climb 35 feet in elevation from west to east making the
profile grades difficult. The alternative would also affect a wider area than Alternative 1. Based on these
factors, Excelsior prefers Alternative 1.
Other Rail Alternatives Considered
The East Range Site could also receive shipments of fuel via water at Taconite Harbor, with
transportation to the site via CE’s privately owned 70-mile rail line that served the former LTV Mining
operations. However, Excelsior does not consider this alternative feasible in the near term.
Roadway Access to the East Range Site
Local Roadways
Roadway transportation in the area of the East Range Site is provided by county roads. The nearest
state highway is State Route (SR) 135, approximately 7 miles west of the site. The primary county road is
CR 110, which departs from SR 135 in Aurora and passes through Hoyt Lakes. CR 110 is the western
terminus of the Superior National Forest Scenic Byway (SR 11). This byway is newly constructed and
connects the north shore of Lake Superior with the Mesabi Iron Range. The east-west section of CR 110 in
Hoyt Lakes passes approximately 1.6 miles south of the East Range Site. Key local roadways are shown in
Figure 2.3-6.
Traffic approaching the East Range Site from the west would travel on CR 110 and turn north onto CR
666 in Hoyt Lakes. This intersection is controlled as a four-way stop. CR 666 extends to the north about
1.6 miles, where it adjoins the eastern boundary of the East Range Site for a distance of about 1.4 miles. It
continues beyond the East Range Site for about 2.1 miles north-northwest to the CE administration
building. Traffic approaching the East Range Site from the east on CR 110 would turn north onto
Hampshire Road in Hoyt Lakes for about 0.3 miles, then turn northeast onto CR 666 toward the site.
Proposed Access Road
CR 666 adjoins the proposed East Range Site and is the most practical choice for public road system
access. The proposed access road (Figure 2.3-6) would consist of a looped roadway intersecting CR 666 at
two locations to provide gentle curves and good sightlines. Traffic would enter the site from the north
access point. During construction and other periods of peak volumes, traffic would exit the site at the
south access point. Having two access points from CR 666 would also provide flexibility in accessing the
Station during construction and when maintenance or construction work is performed on CR 666.
2.3.2.3
Water Sources and Discharges
Process Water Supply
The water requirements for the East Range Site would be less than required by the West Range Site
because an enhanced ZLD system as described in Section 2.2.1.4 (required to comply with stringent
regulations affecting discharges to Lake Superior Basin surface waters) would be used to recycle water to
the maximum extent possible. Water requirements can be reduced by up to 700 gallons per minute per
phase through such recycling efforts. The enhanced ZLD system would allow for the potential use of
wastewaters from other industrial neighbors, but the system would require power above that required for a
station at the West Range Site making the generating station at the East Range Site less efficient and more
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DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
costly to operate. The system also would produce large amounts of residual minerals that would require
landfilling in a permitted facility.
Process water for the East Range Site would be drawn from numerous mine pits located in the vicinity.
The water level in several of these pits is rising, but there is currently no need to control water levels at any
of these pits. Therefore, water could be pumped as needed to support the Mesaba Generating Station.
Mine Pit 2 West Extension would serve as the primary source (similar to the CMP at the West Range Site).
A permanent pumping station would be added to this mine pit, and the pit would receive input from one or
more of the pits listed in Table 2.3-5. Excelsior proposes to link the various mine pits using water intakes,
pump stations, and pipelines as illustrated in Figure 2.3-7. In the event of high inflow rates into Colby
Lake during spring runoff or during high precipitation events, water also may be pumped from Colby Lake
into Mine Pit 2 West Extension.
Table 2.3-5. Process Water Sources – East Range Site
Water Source
Mine Pit 6
Mine Pit 2 West
Mine Pit 2 East
1
900
1
Donora Mine Pit
100
2
Stephens Mine Pit
Knox Mine Pit
Mine Pit 9S
700
1
2
2
150-450
300
130-380
260
190-590
390
20-70
45
90-270
180
0-1,000
1,000
2,000-8,000
4000
2
2
Mine Pit 1 Effluent
3
PolyMet Mining Dewatering
4
Operations
Colby Lake
5
2,900
Total Water Available
12,600
Average Water Requirements (Phase I/Phases I and II)
Peak Water Requirements(Phase I/Phases I and II)
1
Average Annual Flow (gpm)
1,800
Mine Pit 2 West Extension
Mine Pit 3
Estimated Range of Flow (gpm)
1
6
6
3,700/7,200
5,000/10,000
East Range Hydrology Report, MNDNR, Division of Lands and Minerals, Division of Waters, March 2004.
2
Range of flow based on the surface drainage area to the pit and average yearly rates of runoff. This should be considered a
gross approximation as the actual flow rates are likely much more dependent on groundwater components. The
groundwater inflow/outflow component in this area can be highly variable as a result of fractures in the bedrock and/or highly
pervious tailings dikes. Due to the complexity associated with the groundwater component, groundwater inflow/outflow has
not been evaluated.
3
Minnesota Pollution Control Agency NPDES Permit Issued to Mesabi Nugget. Mine Pit 1 effluent represents the wastewater
discharged from Mesabi Nugget’s permitted operation of Mine Pit 1 in accordance with terms of a NPDES Permit.
4
North Met Mine Environmental Assessment Worksheet.
5
Cliffs-Erie Water Appropriation Permit No. 490135; permitted withdrawal is 12,000 gpm daily average over continuous 60day average; 15,000 gpm peak; and 6,307.2 million gallons per year (Assumes no discharge from the operation of the
Mesaba Generating Station).
6
From Table 2.2-3.
2-71
Aurora
lr
Rai
oa
ve
dA
Forestr y Rd
E 3rd Ave S
Aurora
4th
Saint James Mine
White Township
1st St W
S 1st St E
S Ma in St W
Draft EIS
Mesaba Energy Project
nd
I
ro
nR
an ge
Ra i lway
East Range Site
Plant Layout
Municipal Boundaries
Civil Township Boundaries
Kenned y Memorial Dr
Arling
Fo
Proposed Water and Sewer Lines
Proposed Process Water Lines
7R
d
Allen
Moose Mountain
S
LTV
0
3,000
St. Louis County - Central
Coordinate System
Feet
6,000
East Range Water Sources and
Discharges
Figure 2.3-7
Wyman
t 11
5
r es
CR 5 6
Wyman Creek
Hoyt Lakes
Existing Roads
Existing Railroads
ton R d
Hoyt Lakes
Rd
Br andon
Mesaba
Wentworth Mine
Old Mesaba
Erie Mine Number Two Pit
Figure 2.3-7. East Range Water Sources and Discharges
National Energy Technology Lab
ea
m
Geographic Names
Surface Water
Mine Pits
Streams
Legend
iss
ab
Dr
Rd
U.S. Department of Energy
First Creek
lu t
h,
M
Colby Lake
Smolich Island Little Lake
ColbyD
u
Ha
re
hi
Forest Hill Cemetery
Second Creek
Stephens Creek
Stephens Mine
W 5th Ave S
Little Mesaba Lake
Donora Settling Basin and Dike
Knox Mine
e
W 3rd Ave S
4th St W
3rd St W
Erie Mine Number One Pit
Rd
y 135
State Hw
rch
Do
r
st e
ps
S 3rd St W
2nd St E
66
ake
d6
yL
yR
MP RR
Co
t
un
Co lb
in
Min
teel
g
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
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2. PROPOSED ACTION AND ALTERNATIVES
Process Wastewater Discharges
The East Range Site is located within the Lake Superior Basin watershed, which is regulated for
bioaccumulative chemicals of concern (BCCs), such as mercury, in discharges. Water quality criteria
applied to waters located within the Lake Superior Basin are defined at Minnesota Rules 7052.0211
Subpart 3 (“Mixing zones for bioaccumulative chemicals of concern [BCC]”) states:
After March 9, 1998, acute and chronic mixing zones shall not be allowed for new and
expanded discharges of bioaccumulative chemicals of concern (BCC) to the Lake Superior
Basin.
The water quality criterion for mercury in all waters within the Lake Superior Basin watershed is 1.3
nanograms per liter. Sampling in two of the pits from which water supplies for the Mesaba Generating
Station would be appropriated showed median concentrations of 0.75 nanograms per liter for Hg, meaning
that the cycles of concentration at which the cooling towers could operate would be reduced so severely as
to preclude the use of these sources. Excelsior concluded that there are no proven technologies to remove
mercury at such low concentrations at the high flow rates that would be necessary to operate the Mesaba
Generating Station (the peak discharge from Phase I and II would approach 3,500 gallons per minute).
Excelsior’s preferred method for dealing with the mercury discharge limitations at the East Range Site
would be to totally eliminate the discharge of cooling tower blowdown by expanding the use of ZLD
technologies to address all of the generating station’s process wastewater streams. The system would
evaporate any water that could not be reused in the plant processes leaving only a solid stream of salts for
disposal at a licensed treatment/disposal facility. The process would significantly increase the cost of the
Mesaba Generating Station but would enable utilization of the East Range Site.
Excelsior considered discharging process wastewater to the Hoyt Lakes POTW as an alternative, but
the POTW does not have sufficient existing capacity to manage the daily volumes of cooling tower
blowdown. An expansion of the POTW could not be done without a major non-degradation study.
Potable Water Supply
Excelsior considered two alternatives to provide potable water to the Mesaba Generating Station at the
East Range Site. Alternative 1 would rely on a connection to the Hoyt Lakes water system; Alternative 2
would provide an onsite water treatment facility. Alternative 1 is Excelsior’s preferred alternative based on
economic and permitting considerations.
Alternative 1 (Obtain Potable Water from the City of Hoyt Lakes)
The City of Hoyt Lakes 1.5 million gallons per day water treatment plant, which treats surface water
from Colby Lake, has adequate capacity to meet the potable water needs of the Mesaba facility. For
Excelsior’s preferred alternative, a 6-inch diameter pipeline would be constructed approximately 11,000
feet from the East Range Site connecting to a 12-inch water main that serves Minnesota Power (Figure
2.3-7). MP uses an average of 75,000 gallons per day or 100 gallons per minute over a 24-hour period,
which would leave adequate capacity in the existing 12-inch water main to supply the additional potable
water requirement for Phase I and II of 45,000 gallons per day during construction and 7,500 gallons per
day during operations. The proposed 6-inch pipeline would provide the required flow and pressure to the
Mesaba Generating Station without the need for a booster station. The City of Hoyt Lakes would own and
maintain the pipeline, and Excelsior would enter into an agreement with the city to purchase water.
2-73
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Alternative 2 (Construct Onsite Water Treatment System)
Alternative 2 would consist of constructing an on-site treatment facility with the capacity to treat 7,500
gallons per day of potable water for Phases I and II operations. A micro-filtration system similar to that
required for the West Range IGCC Power Station would be used to treat a portion of the process water
procured for project cooling systems that would be pumped to the East Range Site from nearby mine pits.
Chemical treatment of the source water may be required to meet all standards of the Federal Safe Drinking
Water Act and the Minnesota Department of Health and would be determined during detailed engineering
design of the Mesaba Generating Station. Excelsior would own the water treatment facility and be
responsible for its operation and maintenance.
During construction of the Mesaba Generating Station, potable water would not be available until the
process water features were completed. Therefore, potable water would be supplied to the site by other
means (e.g., tanker trucks) during construction.
Domestic Wastewater Treatment Alternatives
Excelsior considered two alternatives for treating and disposing of domestic wastewaters produced
during construction and operation of Phases I and II. Alternative 1 would include the construction of an
onsite wastewater treatment plant. Alternative 2, preferred by Excelsior based on economic and permitting
considerations, would connect the Mesaba Generating Station to the existing Hoyt Lakes wastewater
treatment system. The alternatives are illustrated in Figure 2.3-7.
Alternative 1 (Construct Onsite Wastewater Treatment Facility)
The on-site wastewater treatment facility (WWTF) for the East Range Site would be comparable to the
facility described for the West Range Site. A 12-inch gravity sewer would be constructed to convey treated
effluent to the mine drainage stream running from northeast to southwest through the site and discharging
into Colby Lake.
A disadvantage of this alternative is that the treatment facility would be required to have a capacity of
45,000 gallons per day to meet construction demands, but would receive only about 25 percent of this
design flow once construction was completed. Thus, part of the facility would have to be closed and other
modifications made to the facility after completion of Phase II. Another disadvantage is that effluent from
the system would discharge into Colby Lake, which is the source for the Hoyt Lakes drinking water
treatment plant. A part-time on-site licensed operator would be required to monitor discharges and ensure
that the wastewater treatment facility meets the monitoring and discharge requirements specified in the
NPDES permit.
Alternative 2 (Connect to the Hoyt Lakes Wastewater Treatment System)
Excelsior’s preferred alternative, Alternative 2, would discharge domestic wastewater to the City of
Hoyt Lakes’ wastewater collection and treatment system. The City of Hoyt Lakes owns, operates and
maintains a POTW that receives wastewater from the residential, commercial and industrial establishments
within the service area and discharges treated effluent to Whitewater Lake. The system has a design
capacity of 680,000 gallons per day and receives an average flow of approximately 300,000 gallons per
day.
Alternative 2 would consist of constructing approximately 9,500 feet of 12-inch diameter gravity
sewer, a pump station, and about 2,500 feet of 4-inch force main. The wastewater piping would parallel
the existing HVTL easement along the west side of the proposed property boundary, south to Colby Lake.
2-74
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
A pump station would be located on the north side of Colby Lake. The 12-inch diameter sewer would
have ample capacity to convey the estimated wastewater flow of 45,000 gallons per day during
construction, and the Hoyt Lakes wastewater treatment facility has adequate capacity to treat the estimated
flow from the proposed project. The City of Hoyt Lakes would operate and maintain the sewer line and
would be compensated through sewer user fees.
2.3.2.4
Natural Gas Facilities
NNG is the only pipeline company serving the immediate vicinity of the East Range Site. A 10-inch
diameter branch of NNG’s pipeline from Iron Junction, Minnesota serves the nearby CE plant (the CE
branch) and directly abuts the eastern boundary of the East Range Site. However, this branch line lacks
adequate capacity to supply the Mesaba Generating Station demand. Therefore, to provide natural gas in
the quantity and at the pressure required to supply the Mesaba Generating Station, the following
infrastructure would be required:
•
•
•
Installation of approximately 33 miles of new, 16- to 24-inch pipeline placed within the existing
ROW for the 10-inch CE branch line.
Addition of a new compressor at the existing point where the GLG and NNG pipelines
interconnect.
Installation of an ultrasonic meter facility to serve the Mesaba Generating Station.
The proposed pipeline route is illustrated in Figure 2.3-8. As an interstate pipeline, the East Range
natural gas supply pipeline would not be subject to Minnesota Pipeline Route Permit requirements but
would be permitted by NNG under the Federal Energy Regulatory Commission (FERC) review process.
Approximately 856 residences are located within a half mile of the existing pipeline ROW, 46 of which are
located within 300 feet of the ROW.
2.3.2.5
HVTL Corridors
Overview
Excelsior would configure the high voltage switchyard for the East Range Site at 345-kV for both
phases of the Mesaba Generating Station. The option to operate the switchyard at 345-kV at the start of
Phase I was based on a 5-MW lower net line loss than would occur if the facilities were operated at 230kV. Over the project life, the capacity gain associated with the 345-kV option would offset its higher
capital cost. The high voltage switchyard required to transmit the entire output from Phase I and Phase II
to the point of interconnection with minimum line loss would be installed during construction of Phase I.
No further development would be required to accommodate Phase II.
Point of Interconnection (POI)
Transmission lines in the vicinity of the East Range Site are part of the MP transmission network
known as the “North Shore Loop,” which extends from the east end of the Iron Range, along the north
shore of Lake Superior, and into Duluth. The 115/138-kV transmission facilities that make up this loop are
heavily loaded and currently operate with several special protection schemes involving generation
reduction and/or unit tripping to avoid overloading the remaining transmission facilities during critical
equipment outages. To minimize the impact on this already constrained local transmission system,
Excelsior proposes to construct new HVTLs to the Forbes Substation, approximately 30 miles directly
west-southwest of the East Range Site, which would be the POI for the Mesaba Generating Station (Figure
2.3-8). The Forbes Substation is a major electrical hub on the east end of the Iron Range that has 500-kV,
230-kV, and 115-kV buses owned by both MP (115/230-kV) and Xcel Energy (500-kV).
2-75
Spirit Lake Rd
County Hwy 137
Wolf Rd
Kane Rd
Iron Junction
McDavitt Township
Lavell Township
al
F ay
Eveleth
u
,
Town Line Rd
d
Ce
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e
ake
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B
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ac
Fayal Township
S Airport Dr
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ilw
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Mine Pits
Streams
Existing Roads
Existing Railroads
Surface Water
Legend
Wilso n Rd
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River Dr
Ro
Dr
ple
Balsam La
Oak Rd
Cu
Lon g
rt
La
La
Ba
ss
La
ke
Rd
Rd
Evergreen Rd
Faber Rd
County Hwy 16
La ke
ke
St
Twp Rd 6615
Plant Layout
Municipal Boundaries
Civil Township Boundaries
East Range Site
Moilan Rd
Rd
Pond Rd
ati
Ma
Biwabik Township
Redwood La
Elm Dr
Walnut Dr Ajax Rd
County Hwy 97
Bodas R
d
Rd
y
e
ng
RaHutter Rd
a
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Ra
McKinley
I
nd
e a Pettit Rd
ab
s
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Mi
Gilbert
D
Dr
N Airpo rt Dr
ar
d
an
sl
Tw p R
d 672 2
Dr
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National Energy Technology Lab
Graff Rd
Twp Rd 6845
Borg Rd
Wiley Rd
Old Mesabe Rd
Rd
Bo
n
rg i
n
ga
fi c
Draft EIS
7
ipe
nn
a ci
dP
State Hwy 135
Trigstad Rd 43
Road 45
White Township
Road 37
HVTL Alt 1
HVTL Alt 2
Gas Alt 1
Long Lake Rd
Erickso n Rd
Williams Rd
Colvin Township
38
Road 44
Ro ad 36
Road 37
Road 38
Banks Rd
os e
80
t7
Mo
CR 56 5
Su
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1
Miles
2
St. Louis County - Central
Coordinate System
d
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Town Line Rd
Lin
ir d
Rd
Forest Rt 129
La
Rd
R
17
st 1
Hoyt Lakes
e
For
East Range Natural Gas Pipeline
and HVTL Alternatives
Figure 2.3-8
Farmers Rd
tR
r es
Fo
Forest Rt 1822 Rd
Twp Rd 6511
Road 45
Palo Rd 41
Road 48
Ro a d
E Bodas Rd 39
Road 51
W 5th Ave S
Rd
50 -a
Ro ad
Twp Rd 6525
Loo p 54
Ro ad 54
str y
Fore
Aurora
lio n
Mesaba Energy Project
y
Virginia
Biwabik
il
Verm
U.S. Department of Energy
w
1st St S
9th St N
Sheldon Rd
H
Leonidas
C
y
nt
ou
Virginia Rd
169 US Hwy 169
Iron Junction Rd
Clinton Township
State Hwy 37
Nurmi Rd
6th St
9th Ave W
12th Ave W
County Hwy 102
Voss Rd
ve W
6th
A
13
y
wy
US H
Hanke Rd
Elbow Lake Rd
St
ld
O
at
e
5
ro
n
Kinney
Macon Rd
Macon Rd
d
Mountain Iron
Lilac Rd
1st St
18th Ave
Av
e
rk
Browns Rd
Maury Rd
Fraser Rd
Fraser Rd
Fraser Rd
Rd
S Admiral Rd
Tamarack Rd
3rd Ave N
Unorganized Territory of Hay Lake Township
Hoel Rd
Mineral Ave
Butler Rd
ua
al R
d
Es
Judd Rd
h
q
ua
ga
m
a
Hoover Rd
Peary Rd S Peary Rd
Heritag e Tr
Mc Kinley Rd
Pa
W Long Lake Rd
h
l ut
Du
Wi
Park Dr
Vermilion Tr
Lane 58
Wuori Township
Perala Rd
Stepetz Rd
Hult Rd
Lane 58-a
Lane 58
Coe Rd
R
Long Lake Rd
Q
Lane 57
Co
lby
Rd
ke
La
m
Fi
sh
er
Unorganized Territory of Sand Lake Township
S Fire Tr
US Hw y
53
Miller Trunk Rd
Haller Rd
Lane 57
Mudh en Rd
Fermoy Rd
Scout Camp Rd
Lane 51
Hw
River Rd
Rd
Admir al
Gavin Rd
Rd
Traven Rd
Lane 56
er
Lappi Rd
US Hwy 53
Rd
Clyde Rd
Rd
Little Lake Rd
Clyde Rd
Lane 55
Rd
Leimi Rd
k
Ba
Loon Lake Rd
Co nr ad
S Loon Lake Rd
ta
Vi r
er
ck
Aurora Rd
W
Lane 49
ro und Rd
Lane 50
Cam pg
e
St
Lane 48
78 8
a
e 49
Pin e L
e Lin e
La n
d
Moos
Deer Forest Rd
Rd
Twp Rd 6514
Rd
Pt
an
s
d
tR
nt y
Co u
Ke
n
ge R
Figure 2.3-8. East Range Natural Gas Pipeline
and HVTL Alternatives
Rd
r
Ri d
6
90
or
ve r D
Pike Ri
nts
66
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rv
i
G ia
Rd
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Davis Rd
ty
un
Co
r es
Fo
Re
se
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Tr
2-76
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Based upon preliminary system studies, interconnecting the Project directly to the Forbes 500/230-kV
Substation would result in minimal impact on the underlying MP system, including the already congested
“North Shore Loop.” The MISO generator interconnection process has been initiated to evaluate Forbes as
the POI and to determine what network upgrades are necessary to deliver the output of Phase I to the Xcel
Energy control area (Twin Cities).
HVTL Alternative Routes to Support the East Range Site
Excelsior’s preferred transmission plan for the East Range Site consists of constructing two new
345-kV HVTLs to link the Mesaba Generating Station with the Forbes Substation. As discussed in Section
2.2.2.4, even though one 345-kV HVTL is sufficient to accommodate the combined full load output of
Phases I and II, both new lines must be constructed to address the single-failure criterion concerns.
Excelsior proposes to utilize mostly existing ROWs of 115/138-kV HVTL corridors owned by MP that
interconnect the Syl Laskin Energy Center with the Forbes Substation and minimize any interruption in
electrical service of the existing lines within the corridors selected. Excelsior proposes to use two existing
corridors, the 39L/37L corridor and the 38L corridor, as routes for its two 345-kV HVTLs. These routes
are illustrated in Figure 2.3-8. The corridors span a length of 33 miles between the East Range Site and the
Forbes Substation.
The ROW of a 138-kV line (43L) connecting the Laskin Substation with the CE Substation adjoins the
western boundary of the East Range Site. The southern portion of this line could be replaced with double
circuit structures to carry the lines from the Mesaba Generating Station and the existing 138-kV HVTL to
the Laskin Substation via the existing ROW. However, Excelsior would avoid taking the existing 138-kV
HVTL out of service due to the critical role it plays as part of MP’s North Shore Loop.
To minimize the impact of the Mesaba Generating Station on the already constrained local
transmission system, Excelsior proposes to avoid removing any of the 115/138-kV facilities (the 43L, the
Laskin Substation, or the interconnecting HVTLs between the Laskin Substation and the Forbes
Substation) from service without providing a replacement HVTL. This can be done in one of two ways.
First, the existing 115-kV HVTLs can be handled in “hot” conditions (i.e., HVTLs that are energized)
allowing the new HVTL structures to be constructed within the existing ROW and the existing “hot” lines
to be transferred to the new structures with no interruption of service. Second, Excelsior could acquire a
minimal width of additional ROW along the existing corridor so that new structures can be constructed
with less risk.
To avoid the high cost and dangerous conditions associated with “hot” construction methods, Excelsior
proposes to acquire an additional 30 feet of ROW along one of the routes between the Laskin and Forbes
Substations.
Based on a review of aerial photographs and video taken during overflights of the routes in September
2005, Excelsior identified the 39L/37L corridor as the preferred route along which to acquire the additional
30-foot ROW. For the alternative plan, Excelsior would acquire the additional ROW along the 38L
corridor. The preferred and alternative route plans are described in the following subsections.
Either plan would require the acquisition of two new segments of ROW. One new ROW of about 2
miles in length would extend alongside the existing MP 43L HVTL corridor and would connect the
Mesaba Generating Station with the initiation point of the 39L and 38L corridors. A second section of
about 2 miles of new ROW would be required to link the 39L and 37L corridors near the City of Eveleth.
2-77
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Excelsior’s Preferred Route Plan (Additional Right-of-Way Taken Along 39L/37L Route)
Excelsior considers the best option for widening the 39L corridor to involve acquiring ROW on the
south side of the existing ROW from the Laskin Substation to CR 97, then moving to the north side from
CR 97 to, and across, the Thunderbird Mine. The 39L has single-family residential conflicts in three
potential locations and potentially one industrial site conflict. These narrow sections of ROW would
necessitate either hot line construction or construction in short, scheduled outage windows on the existing
line in affected ROWs. The 37L could be widened on either side of the ROW since the only conflicts
involve existing transmission lines, which may require outage windows for construction.
Approximately 962 residences are located within a half mile of the centerline of the existing ROWs of
the 39L and 37L, of which 369 are located within a quarter mile of the alignment. Approximately 16
residences are located within 300 feet of the ROWs and 33 others are located within 500 feet.
Excelsior’s Alternative Route Plan (Additional Right-of-Way Taken Along 38L Route)
The alternative route plan would involve the same alignments as the preferred route plan. However,
for the alternative plan, Excelsior would acquire the additional 30 feet of ROW along the 38L corridor.
Excelsior determined that the best option for widening the ROW for the 38L corridor would involve
acquiring ROW on the north side of the existing structures. This route conflicts with three to four short
sections of existing 38L ROW where single family residences are located on the north side of the existing
115-kV ROW. The ROW in these locations is too narrow for a 30-foot expansion. Therefore, Excelsior
would propose constructing these sections during short, scheduled line outages, or under hot line
construction, on the existing 38L 115-kV centerline.
Approximately 271 residences are located within a half mile of the centerline of the existing ROWs of
the 38L, of which 116 are located within a quarter mile of the alignment. Approximately 11 residences are
located within 300 feet of the ROWs and 11 others are located within 500 feet.
2.4
SUMMARY COMPARISON OF ALTERNATIVES AND IMPACTS
Table 2.4-1 summarizes the potential impacts for the No Action Alternative in comparison to the
Proposed Action at either of Excelsior’s alternative sites. The baseline conditions that are relevant to the
No Action Alternative are described in Chapter 3 for each resource area. The impacts for each
environmental resource are based on the detailed analyses of impacts in Chapter 4.
2-78
Aesthetics
No Action
No change in
existing
conditions; no
change in
viewsheds or
aesthetic
resources.
East Range
Power Plant Site: Change in viewshed for properties within
sightline of power plant location. Security lighting and aircraft
warning lights for power plant may be visible to closest residences
(~50 within 1 mi). Three public lands are located within 20 mi,
where vapor plumes may be visible at times (Hill Annex Mine State
Park, Forest History Center, and Chippewa National Forest). See
also: Noise.
Power Plant Site: Change in viewshed for properties within
sightline of power plant location. Security lighting and aircraft
warning lights for power plant may be visible to closest residences
(none within 1 mi). Site is on private land within Superior National
Forest boundary, and two other public lands are located within 20
mi, where vapor plumes may be visible. See also: Noise.
Transportation Facilities: Aesthetic impacts from rail and road
construction and operation for closest residences. See also: Noise.
• Rail alt. 1A within 0.5 mi of 16 residences (closest within 400 ft).
• Rail alt. 1B within 0.5 mi of 8 residences (closest, 2,000 ft).
CR 7 realignment and site access road within 0.5 mi of 22
residences (closest within 300 ft).
Transportation Facilities: Aesthetic impacts from rail and road
construction and operation for closest residences. See also:
Noise.
Water Sources and Discharges: Temporary aesthetic impacts
during construction.
• Process water pipelines within 0.5 mi of 104 residences
(four within 500 ft).
• Cooling water effluent pipelines within 0.5 mi of 14 residences
(two within 500 ft).
• Potable/sanitary pipelines within 0.5 mi of 114 residences
(four within 500 ft).
Water Sources and Discharges:
• No residences within 0.5 mi of process water pipeline segments
(closest residence >0.75 mi).
• No cooling water effluent pipeline (enhanced ZLD system).
• No residences within 0.5 mi of potable/sanitary pipelines
(closest >0.75 mi).
Natural Gas Facilities: Temporary aesthetic impacts during
construction. Permanently cleared ROW (low-growing vegetation)
• Alt. 1 within 0.5 mi of 153 residences (three within 300 ft).
• Alt. 2 within 0.5 mi of 339 residences (five within 300 ft).
• Alt. 3 within 0.5 mi of 935 residences (29 within 300 ft).
Natural Gas Facilities: Temporary aesthetic impacts during
construction. Proposed natural gas pipeline on existing pipeline
ROW within 0.5 mi of 856 residences (46 within 300 ft).
HVTL Corridors: Change in viewshed for properties within
sightline of new HVTLs (permanently cleared ROW with lowgrowing vegetation). Increased height and visibility of power poles
in existing HVTL ROWs.
• Route WRA-1 within 0.5 mi of 66 residences (four within 500 ft).
• Route WRA-1A within 0.5 mi of 62 residences (seven within 500
ft).
• Route WRB-2A (existing HVTL ROW) within 0.5 mi of 214
residences (29 within 500 ft).
HVTL Corridors: All HVTLs on existing HVTL ROWs; widening of
one corridor required (permanently cleared ROW with low-growing
vegetation). Increased height and visibility of power poles for
properties within sightline of HVTLs.
• 38L corridor within 0.5 mi of 271 residences (22 within 500 ft).
• 39L/37L corridors within 0.5 mi of 962 residences
(49 within 500 ft).
No residences within 0.5 mi of either rail alignment alternative
(closest, ~1 mi).
No residences within 0.5 mi of site access road (closest, >1 mi).
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
2-79
West Range
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Air Quality and Climate
No Action
No change in
existing conditions;
no new emissions
affecting air quality.
West Range
East Range
Power Plant Site: Annual emissions of criteria pollutants would
include 1,390 tons of SO2, 2,872 tons of NOX, 2,539 tons of CO,
0.03 tons of Pb, 493 tons of PM10, and 197 tons of VOCs;
therefore the facility would be a major source of SO2, NOX, CO,
PM10, and VOCs under the PSD regulations. Predicted
concentrations for each pollutant would be below allowable levels
under National Ambient Air Quality Standards (NAAQS) and
Minnesota Ambient Air Quality Standards (MAAQS). The plant
would potentially emit 0.026 tons per year (tpy) of mercury (below
the HAP threshold of 25 tpy) and would include additional
technologies to reduce mercury and meet the requirements of the
Clean Air Mercury Rule (CAMR). Process modification and
improved work practices would be implemented to limit potential
annual emission rates.
Power Plant Site: Annual emissions of criteria pollutants would
include 1,390 tons of SO2, 2,872 tons of NOX, 2,539 tons of CO,
0.03 tons of Pb, 709 tons of PM10, and 197 tons of VOC; therefore
the facility would be a major source of SO2, NOX, CO, PM10, and
VOCs under the PSD regulations. Because of the source water
quality at the East Range Site, emissions of PM10 would be higher
than at the West Range Site. Predicted concentrations for each
pollutant would be below allowable levels under NAAQS and
MAAQS The plant would potentially emit 0.026 tpy of mercury
(below the HAP of 25 tpy threshold) and would include additional
technologies to reduce mercury and meet the requirements of the
CAMR. Process modification and improved work practices would
be implemented to limit potential annual emission rates.
Class II PSD increment analysis indicates that the project would
comply with all state and Federal increment limits.
Class I area impacts analysis indicates that the project impacts
would be below allowable increments for all pollutants.
Class I area impacts analysis indicates that the project impacts
would be below allowable increments for all pollutants.
Visibility/regional haze analysis in Class I areas predict that, as a
result of the Proposed Action, there would be days with greater
than 5% visibility (with a potential for detectable change) or greater
than 10% visibility ( a level of unacceptable degradation) at some
point each year. Within the BWCAW 92 to 131 days of >5%
visibility and 44 to 69 days of >10% visibility. At VNP, it is 15 to 26
days of >5% visibility and 4 to 8 days at >10% visibility. However,
predicted impacts would occur during days of very high relative
humidity in winter and would coincide with days of natural visibility
degradation due to fog, precipitation, or low clouds.
Without mitigation or capture/storage (see Section 5.1.2.1), the
plant would emit approximately 9.4 to 10.6 million tpy of CO2;
thereby adding to the approximately 2.3 billion metric tpy of CO2
from electric power sources nationwide.
Class II PSD increment analysis indicates that the project would
comply with all state and Federal increment limits.
Without mitigation or capture/storage (see Section 5.1.2.1), the
plant would emit approximately 9.4 to 10.6 million tpy of CO2;
thereby adding to the approximately 2.3 billion metric tpy of CO2
from electric power sources nationwide.
2-80
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Visibility/regional haze analysis in Class I areas predict that, as a
result of the Proposed Action, there would be days with greater
than 5% visibility (with a potential for detectable change) or
greater than 10% visibility ( a level of unacceptable degradation)
at some point each year. Within the Boundary Waters Canoe
Area Wilderness (BWCAW), it is 17 to 39 days of >5% visibility
and 6 to 15 days of >10% visibility. At Voyageurs National Park
(VNP), it is 16 to 25 days with >5% visibility and 1 to 4 days >10%
visibility. However, predicted impacts would occur during days of
very high relative humidity in winter and would coincide with days
of natural visibility degradation due to fog, precipitation, or low
clouds.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Air Quality and Climate
No Action
West Range
East Range
Odors from H2S and NH3 would be negligible, because associated
processes would be enclosed.
Odors from H2S and NH3 would be negligible, because associated
processes would be enclosed.
The National Park Service (NPS) has established a Deposition
Analysis Threshold (DAT) of 0.01 kg/hectare/yr for both sulfur (S)
and nitrogen (N) deposition in Class I areas, which is the level
below which adverse impacts are not anticipated. The deposition
of S in VNP would be very close to the DAT, and deposition of N
would be below the DAT. Because the modeled deposition values
represent the highest deposition for any receptor in the Class I
area, and the annual emissions for the Mesaba plant used in the
model are very conservative, it is unlikely that the DAT threshold
for S deposition would be exceeded at any point in VNP.
Deposition values for S and N in the BWCAW would be below the
DAT.
The DAT of 0.01 kg/hectare/yr established by NPS for both sulfur
(S) and nitrogen (N) deposition in Class I areas would apply to the
East Range Site. The deposition of S in VNP would be very close
to the DAT, and deposition of N would be below the DAT.
Because the modeled deposition values represent the highest
deposition for any receptor in the Class I area, and the annual
emissions for the Mesaba plant used in the model are very
conservative, it is unlikely that the DAT threshold for S deposition
would be exceeded at any point in VNP. Deposition values for S
and N in the BWCAW would be below the DAT.
3
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
3
Deposition of mercury would be 1.3 x 10-5 µg/m at a rate of 0.01
cm/sec over lakes and 0.05 cm/sec over the rest of the watershed.
Colby Lake would be within the release plume of future facility
emissions; therefore, the concentration and rate of deposition was
used to determine the incremental contribution of mercury in fish
tissues caught from Colby Lake based on the analytical results for
Big Diamond Lake (see Section 4.17, Health and Safety). Mercury
emissions and subsequent deposition would be reduced by the
high efficiency IGCC technology combined with the design-added
mercury removal carbon absorption beds to ensure that mercury
emissions from the facility would be less than 10 percent of the
mercury in the feedstock.
Transportation Facilities: Fugitive dust emissions during
construction and operations from vehicle traffic, transportation of
materials, and material handling. The impacts would be localized
and would decrease with distance from site and alignments.
Transportation Facilities: Fugitive dust emissions during
construction and operations from vehicle traffic, transportation of
materials, and material handling. The impacts would be localized
and would decrease with distance from site and alignments.
Water Sources and Discharges, Natural Gas Facilities, and
HVTL Corridors: Fugitive dust emissions during construction
related to the respective lengths of potential alignments.
Water Sources and Discharges, Natural Gas Facilities, and
HVTL Corridors: Fugitive dust emissions during construction
related to the respective lengths of potential alignments.
2-81
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Deposition of mercury would be 1.3 x 10-5 µg/m at a rate of 0.01
cm/sec over lakes and 0.05 cm/sec over the rest of the
watershed. Big Diamond Lake would be within the release plume
of future facility emissions; therefore, the concentration and rate of
deposition was used to determine the incremental contribution of
mercury in fish tissues caught from Big Diamond Lake (see
Section 4.17, Health and Safety). Mercury emissions and
subsequent deposition would be reduced by the high efficiency
IGCC technology combined with the design-added mercury
removal carbon absorption beds to ensure that mercury emissions
from the facility would be less than 10 percent of the mercury in
the feedstock.
Geology and Soils
No Action
No change in
existing conditions;
no new land
disturbance.
West Range
East Range
Power Plant Site: The plant footprint (Phases I & II) would
occupy approximately 192 ac. Site grading and preparation for
3
the plant footprint would require approximately 2,975,000 yd of
3
cut land and approximately 1,750,000 yd of fill land.
Power Plant Site: The plant footprint (Phases I & II) would occupy
approximately 192 ac. Based on site topography, grading and
preparation for the plant footprint would require less cut and fill
volume than the West Range Site.
Although the site is situated on 137 ac of soils classified as prime
farmland or prime farmland if drained, no agriculture uses
currently occur on the property. The Minnesota Prime Farmland
Exclusion Rule does not apply to the site which is in or within 2 mi
of a statutory city.
There are no areas designated as prime farmland within the East
Range Site boundary and no agriculture uses currently occur on
the property. The Minnesota Prime Farmland Exclusion Rule does
not apply to the site which is in or within 2 mi of a statutory city.
Transportation Facilities: Construction impacts from rail and
road alignments. No long-term operational impacts.
• Rail alt. 1A would disturb 139 ac, require approximately
3
3
3,000,000 yd of cut land and 2,000,000 yd of fill land, and
occupy approximately 38 ac of prime farmland soils.
• Rail alt. 1B would disturb 179 ac, require approximately
3
3
8,500,000 yd of cut land and 2,000,000 yd of fill land, and
occupy approximately 40 ac of prime farmland soils.
CR 7 realignment and site access road construction would disturb
122 ac and occupy approximately 55 ac of prime farmland soil
classifications.
Transportation Facilities: Construction impacts from rail and
road alignments. No long-term operational impacts.
• Rail alt. 1 would disturb 77 ac and require approximately
3
2,300,000 yd of cut land and less fill than at West Range.
• Rail alt. 2 would disturb 74 ac and require approximately
3
2,100,000 yd of cut land and less fill than at West Range.
Access road construction would disturb 45 ac.
Water Sources and Discharges: Construction of process water
supply pipelines would disturb 165 ac and occupy 57 ac of prime
farmland soils. Cooling water effluent pipelines would disturb 83
ac and occupy 40 ac of prime farmland soils. Potable/sanitary
pipelines would disturb 34 ac and occupy 8 ac of prime farmland.
Water Sources and Discharges: Construction of process water
supply pipelines would disturb approximately 109 ac. No cooling
water effluent pipelines required (due to the use of an enhanced
ZLD system). Potable/sanitary pipelines would disturb 25 ac.
Impacts on prime farmland could not be determined (soil survey for
St. Louis County not complete).
Natural Gas Facilities: Construction impacts of alignments.
• Alternative 1 would disturb 160 ac and occupy 81 ac of prime
farmland soils.
• Alternative 2 would disturb 171 ac and occupy 86 ac of prime
farmland soils.
• Alternative 3 would disturb 142 ac and occupy 66 ac of prime
farmland soils.
Natural Gas Facilities: Pipeline would be constructed within an
existing gas pipeline ROW requiring disturbance of 350 ac.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Impacts on prime farmland could not be determined from data
available, because the soil survey for St. Louis County has not
been completed.
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
2-82
Geology and Soils
No Action
West Range
East Range
HVTL Corridors: Impacts of alignments.
• Route WRA-1 would disturb 134 ac and occupy <1 ac of prime
farmland soils.
• Route WRA-1A would disturb 151 ac and occupy <1 ac of prime
farmland soils.
• Route WRB-2A would disturb land on an existing HVTL ROW.
HVTL Corridors: All HVTLs constructed on existing HVTL ROWs
with new towers; widening of one or the other corridor required.
• 38L corridor would disturb 455 ac.
• 39L/37L corridors would disturb 457 ac.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Water Resources
No Action
East Range
Power Plant Site: Disturbance of land areas during plant
construction, as summarized for Geology and Soils, would create
potential for erosion and sedimentation. Impacts on surface
waters would be minimized through the implementation of a
sediment and erosion control (SEC) plan required for a National
Pollutant Discharge Elimination System (NPDES) General
Construction Permit. Potential impacts during operation would be
minimized through the implementation of a stormwater pollution
prevention plan (SWPPP) based on state requirements. Runoff
from the plant site and coal pile areas would be routed through
stormwater management ponds and oil/water separators, limiting
the discharge of pollutants. No impacts on groundwater from the
construction or operation of the plant are expected.
Power Plant Site: Disturbance of land areas during plant
construction, as summarized for Geology and Soils, would create
potential for erosion and sedimentation. Impacts on surface
waters would be minimized through the implementation of a SEC
plan required for a NPDES General Construction Permit. Potential
impacts during operation would be minimized through the
implementation of a SWPPP based on state requirements. Runoff
from the plant site and coal pile areas would be routed through
stormwater management ponds and oil/water separators, limiting
the discharge of pollutants. No impacts on groundwater from the
construction or operation of the plant are expected.
Transportation Facilities: Disturbance of land areas during road
and railway construction, as described for Geology and Soils.
Impacts on surface waters would be minimized through the
implementation of a SEC plan required for a NPDES General
Construction Permit. No impacts on surface waters or
groundwater from the operation of the road and railway expected.
Transportation Facilities: Disturbance of land areas during road
and railway construction, as described for Geology and Soils.
Impacts on surface waters would be minimized through the
implementation of a SEC plan required for a NPDES General
Construction Permit. No impacts on surface waters or
groundwater from the operation of the road and railway expected.
2-83
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
No changes to
water resources in
the project area.
The Hill-Annex
Mine Park would
not be dewatered to
the level necessary
to view all the
historical structures
in the mine pit.
Also, the CMP will
likely overflow
within the next 4 to
8 years, potentially
causing flooding
within Coleraine
and Bovey.
West Range
Water Resources
Water Sources and Discharges: Average process water
demand of 8,800 – 10,300 gpm (15,200 gpm peak) from CMP and
interconnected mine pits would not adversely affect water
sources. Lowering of water level in CMP would reduce potential
for overflow impacts on Coleraine and Bovey. Average cooling
water discharges of 3,500 gpm (6,000 gpm peak) to CMP; 825
gpm (6,000 gpm peak) to Holman Lake. Discharges of some
parameters may exceed water quality standards, however, the
cumulative effects on receiving waters would be monitored by
operating staff to ensure parameter concentrations do not exceed
NPDES permit limits. Potable water use of 7,500 gpd during
operation would not adversely affect Taconite water system,
however, the existing water system does not have sufficient
capacity to provide the 45,000 gpd during construction. Planned
improvements to the system would be necessary to handle this
demand, or Excelsior would provide potable water via truck during
construction. Domestic wastewater discharges would be within the
effective treatment capacity of the regional facility.
Water Sources and Discharges: Average process water demand
of 7,400 gpm (10,000 gpm peak) from interconnected mine pits
would not adversely affect water sources. No direct discharge of
cooling water to surface waters would occur (due to the enhanced
ZLD system). Potable water use of 45,000 gpd during construction
and 7,500 gpd during operation would not adversely affect the
Hoyt Lakes water system. Domestic wastewater discharges would
be within the effective treatment capacity of the municipal facility.
Natural Gas Facilities: Best management practices (BMPs)
would be implemented to minimize impacts from erosion and
sedimentation during construction.
Natural Gas Facilities: BMPs would be implemented to minimize
impacts from erosion and sedimentation during construction.
HVTL Corridors: BMPs would be implemented to minimize
impacts from erosion and sedimentation during construction.
HVTL Corridors: BMPs would be implemented to minimize
impacts from erosion and sedimentation during construction.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
2-84
Floodplains
No Action
No change in
existing conditions;
no impact on
floodplains.
West Range
East Range
Power Plant Site: No impact. The site is approximately one mile
from the nearest 100-year floodplain along the Prairie River.
Power Plant Site: No impact. The site is outside of the nearest
100-year floodplain of the Partridge River.
Transportation Facilities: No impact. Proposed rail and access
road alignments would be located outside of the 100-year
floodplain.
Transportation Facilities: No impact. Proposed rail and access
road alignments would be located outside of the 100-year
floodplain.
Water Sources and Discharges: No impact. Construction of
pipelines would occur outside of the 100-year floodplain.
Water Sources and Discharges: No impact. Construction of
pipelines would occur outside of the 100-year floodplain.
Natural Gas Facilities: Temporary impacts may occur during
construction of natural gas pipeline alt. 1, 2, or 3 as a result of
trenching, stockpiling of soil, and storage of equipment where
pipelines would cross the 100-year floodplain of Swan River or
Prairie River However, impacts would be mitigated through the
use of construction BMPs, and floodplain contours would be
restored following construction. No permanent impacts on flood
elevations would occur, because the pipelines would be located
below the land surface.
Natural Gas Facilities: Temporary impacts may occur during
construction of the natural gas pipeline as a result of trenching,
stockpiling of soil, and storage of equipment where the pipeline
would cross the 100-year floodplain of the Partridge River.
However, impacts would be mitigated through the use of
construction BMPs, and floodplain contours would be restored
following construction. No permanent impacts on flood elevations
would occur, because the pipelines would be located below the
land surface.
HVTL Corridors: No impact. Construction of HVTLs would occur
outside of the 100-year floodplain.
HVTL Corridors: Temporary impacts may occur during widening
of HVTL corridors (38L or 39L/37L) where the HVTLs would cross
the 100-year floodplain of the Partridge, Embarrass, or East Two
River. No permanent impact on flood elevations would occur,
because permanent structures would be limited to HVTL towers
that have small footprints.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
2-85
Wetlands
No Action
No change in
existing conditions;
wetlands would
remain in their
current status.
West Range
East Range
Power Plant Site: Permanent wetland loss or alteration relating to
the plant footprint (Phases I & II) would be approximately 31 ac.
Power Plant Site: Permanent wetland loss or alteration relating to
the plant footprint (Phases I & II) would be approximately 16 ac.
Transportation Facilities: Construction of rail and road access
would result in loss or destruction of wetlands in areas of
permanent impact (without mitigation). Areas of temporary impact
could result in the alteration of wetland types and functions:
• Rail alt. 1A would have a temporary impact on 26 ac and a
permanent impact on 77 ac (including center loop).
• Rail alt. 1B would have a temporary impact on impact on18 ac
and a permanent impact on 64 ac (including center loop).
CR 7 realignment and access road construction would impact 10
ac for temporary ROW; 6 ac for permanent ROW.
Transportation Facilities: Construction of rail and road access
would result in loss or destruction of wetlands in areas of
permanent impact (without mitigation). Areas of temporary impact
could result in the alteration of wetland types and functions:
• Rail alt. 1 would have a temporary impact on 17 ac and a
permanent impact on 59 ac (including center loop).
• Rail alt. 2 would have a temporary impact on 18 ac and a
permanent impact on 13 ac (no center loop).
Access road construction would impact 6 ac for temporary ROW; 3
ac for permanent ROW.
Water Sources and Discharges: Construction of pipelines:
• Process water supply pipelines would alter 12 ac for temporary
ROW (8 ac lost or altered in permanent ROW).
• Cooling water effluent pipelines would alter 26 ac for temporary
ROW (18 ac lost or altered in permanent ROW).
• Potable/sanitary pipelines would alter 4 ac for temporary ROW
(2 ac lost or altered in the permanent ROW).
Water Sources and Discharges: Construction of pipelines:
• Process water supply pipelines would alter <3 ac for temporary
ROW (<2 ac lost or altered in permanent ROW).
• No cooling water effluent pipelines required (due to the
enhanced ZLD system).
• No wetlands are located in the alignments for potable/sanitary
pipelines.
HVTL Corridors: Construction of HVTLs.
• Route WRA-1 would alter 30 ac for clearing ROW (<1 ac lost for
tower emplacements).
• Route WRA-1A would alter 25 ac for clearing ROW (<1 ac lost
for tower emplacements).
• Route WRB-2A would be constructed in existing HVTL ROWs;
no additional wetland impacts for clearing anticipated (<1 ac lost
for tower emplacements).
Natural Gas Facilities: Construction of the natural gas pipeline
would alter 67 ac for temporary ROW (47 ac lost or altered in the
permanent ROW).
HVTL Corridors: All HVTLs would be constructed on existing
HVTL ROWs with new towers; widening of one or the other
corridor would be required.
• 38L corridor would alter 29 ac for clearing ROW (<1 ac lost for
tower emplacements).
• 39L/37L corridors would alter 27 ac for clearing ROW (<1 ac lost
for tower emplacements).
2-86
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Natural Gas Facilities: Construction of pipelines:
• Alt. 1 would alter 25 ac for temporary ROW (17 ac lost or altered
in the permanent ROW).
• Alt. 2 would alter 29 ac for temporary ROW (18 ac lost or altered
in the permanent ROW).
• Alt. 3 would alter 13 ac for temporary ROW (9 ac lost or altered
in the permanent ROW).
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Biological Resources
No Action
No change in
existing conditions;
biological resources
would remain in
current status.
East Range
Power Plant Site: Approximately 155 ac of vegetation
communities would be lost or destroyed from construction for
Phase I and Phase II. Much of the Iron Range is within the
distributional range of the bald eagle, Canada lynx, and gray wolf,
which are Federally listed species. The U.S. Fish and Wildlife
Service (USFWS) has concurred with DOE’s determination that
the project is not likely to adversely affect the bald eagle and has
agreed to prepare a Biological Opinion (to be included in the Final
EIS) addressing potential effects on the lynx and wolf. Eight
state-listed plant species (17 occurrences) in general area of site,
but no occurrences within the site boundary. Possible, but
unlikely, that these species could be affected.
Power Plant Site: Approximately 167 ac of vegetation
communities would be lost or destroyed from construction for
Phase I and Phase II. Much of the Iron Range is within the
distributional range of the bald eagle, Canada lynx, and gray wolf,
which are Federally listed species. USFWS has concurred with
DOE’s determination that the project is not likely to adversely affect
the bald eagle. In the event that the East Range Site would be
selected for the Proposed Action, a Biological Opinion from the
USFWS would be required to address potential effects on the lynx
and wolf. No known occurrences of state-listed species within 1 mi
of site.
Transportation Facilities: Construction of rail and road access:
• Rail alt. 1A: 54 ac (104 ac within center loop) of vegetation
communities lost or destroyed. No known occurrences of statelisted species within 1 mi.
Access roads would result in the loss or destruction of 54 ac of
vegetation communities. No known occurrences of state-listed
species within 1 mi.
Transportation Facilities: Construction of rail and road access:
• Rail alt. 1 would result in the loss or destruction of 142 ac
(including center loop with 104 ac of impacts) of vegetation
communities. Two stream crossings could cause direct mortality
to aquatic biota, habitat fragmentation/conversion, increased
water temperature, and increased sedimentation (causing loss in
macroinvertebrate communities). No known occurrences of
state-listed species within 1 mi.
• Rail alt. 2 would result in the loss or destruction of 41 ac of
vegetation communities. One stream crossing could cause direct
mortality to aquatic biota, habitat fragmentation/conversion,
increased water temperature, and increased sedimentation
(causing loss in macroinvertebrate communities). No known
occurrences of state-listed species within 1 mi.
Access roads would result in the loss or destruction of 28 ac of
vegetation communities. No known occurrences of state-listed
species within 1 mi.
Water Sources and Discharges: Construction of pipelines:
Water Sources and Discharges: Construction of pipelines:
Process water supply pipelines would result in the loss or
destruction of 53 ac of vegetation communities. Five known
occurrences of five state-listed plant species within 1 mi of
proposed pipeline. Possible, but unlikely, that these species could
be affected by construction (usually found in different habitat
types).
Process water supply pipelines would result in the loss or
destruction of 34 ac of vegetation communities. Four stream
crossings could temporarily cause increased sedimentation
(causing loss in macroinvertebrate communities) and increased
biochemical oxygen demand during construction. No known
occurrences of state-listed species within 1 mi.
• Rail alt. 1B: 55 ac (116 ac within center loop) of vegetation
communities lost or destroyed. No known occurrences of statelisted species within 1 mi.
2-87
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
West Range
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Biological Resources
No Action
East Range
Cooling water effluent pipelines would impact:
• Alt 1 would cause the loss or destruction of 25 ac of vegetation.
No known occurrences of state-listed species within 1 mi.
• Alt 2 would cause the loss or destruction of 10 ac of vegetation.
No known occurrences of state-listed species within 1 mi.
Potable/sanitary pipelines would result in the loss or destruction of
7 ac of vegetation communities
No cooling water effluent pipelines are expected (due to the use of
an enhanced ZLD system).
Natural Gas Facilities:
• Alt 1 would cause the loss or destruction of 71 ac of vegetation
communities. Nine known occurrences of seven state-listed
plant species within 1 mi of proposed pipeline. Possible, but
unlikely, that these species could be affected by construction
(usually found in different habitat types).
• Alt 2 would cause the loss or destruction of 43 ac of vegetation
communities. Three known occurrences of one state-listed
plant species within 1 mi of proposed pipeline. Possible, but
unlikely, that these species could be affected by construction
(usually found in different habitat types).
• Alt. 3 would cause the loss or destruction of 43 ac of vegetation
communities. No known occurrences of state-listed species
within 1 mi.
Natural Gas Facilities:
HVTL Corridors:
• Route WRA-1 would cause the loss or destruction of 93 ac for
tree and shrub clearing resulting in habitat conversion within the
ROW. Seven occurrences of five state-listed plant species
within 1 mi of proposed HVTL, which could be affected during
construction and operation.
• Route WRA-1A would cause the loss or destruction of 72 ac for
tree and shrub clearing resulting in habitat conversion within the
ROW. Seven occurrences of five state-listed plant species
within 1 mi of proposed HVTL, which could be affected during
construction and operation.
• Route WRB-2A would not have a permanent impact on
vegetation because it would be located within an existing HVTL
corridor. Eleven occurrences of eight state-listed plant species
and one occurrence of a state-listed animal species within 1 mi
of proposed HVTL, which could be affected during construction
and operation.
HVTL Corridors:
• 38L corridor would cause the loss or destruction of 89 ac for tree
and shrub clearing resulting in habitat conversion as long as the
ROW is maintained. Two occurrences of two state-listed plant
species and 16 occurrences of three state-listed animal species
within 1 mi of proposed HVTL, which could be affected during
construction and operation.
• 39L/37L corridors would cause the loss or destruction of 86 ac
for tree and shrub clearing resulting in habitat conversion as long
as the ROW is maintained. Eight occurrences of five state-listed
plant species and eight occurrences of two state-listed animal
species within 1 mi of proposed HVTL, which could be affected
during construction and operation.
Potable/sanitary pipelines would cause the loss or destruction of 5
ac of vegetation communities. No known occurrences of statelisted species within 1 mi of potable/sanitary pipelines.
Proposed alignment would cause the loss or destruction of 187 ac
of vegetation communities. Five occurrences of three state-listed
plant species and seven occurrences of two state-listed animal
species within 1 mi of proposed pipeline. Possible that
construction could affect these species.
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
2-88
West Range
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Cultural Resources
No Action
West Range
Power Plant Site: Located within Western Mesabi Iron Range
Early Mining Landscape District. MN State Historic Preservation
Office (SHPO) has 11 historic properties recorded within the area
of potential effect for the West Range Site and corridors.
Coordination with SHPO required during construction to avoid or
minimize potential impacts to the historic character of the District.
No known archaeological resources or Native American cultural
resources known to exist within 1 mi of site.
The potential for the occurrence of archaeological resources is
high within 55 ac (1%) and moderate on 108 ac (2%) of the site.
Consistent with the recommendations of the SHPO, a Phase I
archaeological survey of locations with high and medium potential
was conducted in 2007. Although not yet final, the survey did not
uncover any previously unknown resources within the site
boundaries.
No new structures
built, no
archaeological or
Native American
sites disturbed.
Transportation Facilities, Water Sources and Discharges,
Natural Gas Facilities, HVTL Corridors: Located within
Western Mesabi Iron Range Early Mining Landscape District.
SHPO has 11 historic properties recorded within the area of
potential effect for site and corridors. Coordination with SHPO
required during construction to avoid or minimize potential
impacts to the historic character of the District. No known
archaeological resources or Native American cultural resources
exist within the transportation or utility corridors.
Archaeological surveys would be conducted only in those
corridors to be permitted by the PUC if the West Range site were
selected for permitting. Although surveys would necessarily be
completed after the DOE Record of Decision, the Record of
Decision would be conditional upon implementing the provisions
of an agreement between DOE, SHPO, and appropriate parties
for the identification and protection of resources.
Power Plant Site: No known archaeological sites or Native
American cultural resources identified within 1 mi of the site.
The study area (30,471 ac) included the site and associated
transportation and utility corridors. A total of 4,862 ac (16%) of the
study area has a high potential for archaeological resources and
457 ac (1.5%) has a moderate potential for archaeological
resources.
Phase I surveys are complete, and the SHPO has agreed that no
further study is needed, provided that there would be no terrain
disturbance at the Longyear historic site.
Transportation Facilities: Included in the discussion for the plant
site above.
Water Sources and Discharges: The water pipeline corridors
would be located within previously disturbed areas; therefore,
these corridors would not be expected to contain archaeological or
historical resources.
Natural Gas Facilities: The natural gas pipeline corridor would
follow an existing ROW; therefore, no archaeological or historical
resources are anticipated.
HVTL Corridors: The proposed HVTLs would follow existing
HVTL corridors, which would minimize potential for impacts.
There are two known archaeological sites located within 0.25 mi of
the 39L/37L corridors; however, they are outside of the
construction ROW. One National Register of Historic Places
(NRHP)-listed building and one potentially eligible building are
within the town of Eveleth in the vicinity of the 39L/37L route. One
eligible site within the HVTL visual area of potential effect crossed
by the HVTL corridor south of the plant site.
2-89
Archaeological surveys would be conducted only in those corridors
to be permitted by the PUC if the East Range site were selected
for permitting. Although surveys would necessarily be completed
after the DOE Record of Decision, the Record of Decision would
be conditional upon implementing the provisions of an agreement
between DOE, SHPO, and appropriate parties for the identification
and protection of resources
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
A total of 330 ac (5%) of high potential for archaeological
resources and 580 ac (12%) of moderate potential for
archaeological resources exists along the HVTLs, rail line, and
pipeline corridors (combined for all transportation and utility
corridors).
East Range
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Land Use
No Action
No change in land
use; sites and
corridors would
remain in current
status.
West Range
East Range
Power Plant Site: Generating station on 1,260-ac site, currently
undeveloped and zoned for industrial use. ~50 residential
properties within 1 mi of footprint (closest, 0.71 mi); buffered by
~0.5 mi of dense woodlands. No conflict with local or regional
zoning ordinances or land use plans.
Power Plant Site: Generating station on 810-ac site, currently
undeveloped and zoned for mining use. No residential properties
within 1 mi of footprint (closest, 1.28 mi); buffered by ~0.5 mi of
dense woodlands. No conflict with local or regional zoning
ordinances or land use plans.
No use of eminent domain is needed to acquire the site footprint
and its surrounding buffer land. The use of eminent domain as
allowed by MN Statutes 216B.1694 may be necessary to acquire
some public and private lands or easements if agreements to
purchase such lands or easements (for associated facilities,
utilities, or transportation infrastructure; or to interconnect the
Project with such features and available water resources) cannot
be negotiated with property owners.
No use of eminent domain is needed to acquire the site footprint
and its surrounding buffer land. The use of eminent domain as
allowed by MN Statutes 216B.1694 may be necessary to acquire
some public and private lands or easements if agreements to
purchase such lands or easements (for associated facilities,
utilities, or transportation infrastructure; or to interconnect the
Project with such features and available water resources) cannot
be negotiated with property owners.
Transportation Facilities: Rail alignment alternatives:
• Alt. 1A within 0.5 mi of 16 residences (closest, 400 ft).
• Alt. 1B within 0.5 mi of 8 residences (closest, 2,000 ft).
CR 7 realignment and site access road within 0.5 mi of 22
residences (closest within 300 ft).
Transportation Facilities: Rail and road alignments:
Water Sources and Discharges:
• Process water pipelines within 0.5 mi of 104 residences (4 within
500 ft).
• Cooling water effluent pipelines within 0.5 mi of 14 residences (2
within 500 ft).
• Potable/sanitary pipelines within 0.5 mi of 114 residences (4
within 500 ft).
Water Sources and Discharges:
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
No residences within 0.5 mi of either rail alignment alternative
(closest ~1 mi).
No residences within 0.5 mi of site access road (closest >1 mi).
2-90
Natural Gas Facilities: Natural gas pipelines:
• Alt. 1 within 0.5 mi of 153 residences (3 within 300 ft).
• Alt. 2 within 0.5 mi of 339 residences (5 within 300 ft).
• Alt. 3 within 0.5 mi of 935 residences (29 within 300 ft).
Natural Gas Facilities: Natural gas pipeline on existing ROW
within 0.5 mi of 856 residences (46 within 300 ft).
HVTL Corridors: HVTL routes:
• Route WRA-1 within 0.5 mi of 66 residences (4 within 500 ft).
• Route WRA-1A within 0.5 mi of 62 residences (7 within 500 ft).
• Route WRB-2A within 0.5 mi of 214 residences
(29 within 500 ft).
NOTE: See Geology and Soils for acreages affected.
HVTL Corridors: All HVTL routes on existing ROWs; widening of
one or the other corridor would be required.
• 38L corridor within 0.5 mi of 271 residences (22 within 500 ft).
• 39L/37L corridors within 0.5 mi of 962 residences
(49 within 500 ft).
NOTE: See Geology and Soils for acreages affected.
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
• No residences within 0.5 mi of process water pipeline segments
(closest >0.75 mi).
• No cooling water effluent pipeline (enhanced ZLD system).
• No residences within 0.5 mi of potable/sanitary pipelines (closest
>0.75 mi).
Socioeconomics
No Action
No change in
existing
socioeconomic
conditions; no
potential for
economic stimulus
from proposed
project.
West Range
East Range
General: Project spending and creation of new construction and
operation jobs would provide value added benefits to regional
economy ($3.1 billion over 6 years during construction; $1.1
billion/yr during operation of both phases; the power plant would be
expected to operate commercially for 20 years or more).
Power Plant Site: No displacement of population, housing,
businesses, or jobs. Ten or more residential properties closest to
the plant footprint could experience impacts on property values
based on proximity to facility and resulting aesthetic and noise
impacts. Potential temporary adverse impacts on housing
demand related to influx of workers during peak construction
(>1,500/yr in 2009-11); less than 3,000 housing units in Census
Tract 9810, of which 513 were vacant (non-seasonal) or rental
units in 2000.
Power Plant Site: No displacement of population, housing,
businesses, or jobs. No impact on property values anticipated
based on distances to nearest residences. Potential temporary
adverse impacts on housing demand related to influx of workers
during peak construction (>1,500/yr in 2009-11); less than 1,000
housing units in Hoyt Lakes (Census Tract 140), of which 143 were
vacant (non-seasonal) or rental units in 2000.
Transportation Facilities: No displacement of population,
housing, businesses, or jobs. Three residences within 1,000 ft of
Rail Alignment Alternative 1A could experience impacts on
property values due to proximity and resulting aesthetic and noise
impacts. Realignment of CR 7 by Itasca County (connected
action) may influence local housing development in vicinity.
Transportation Facilities: No displacement of population,
housing, businesses, or jobs. No impact on property values
anticipated based on distances to nearest residences.
Water Sources and Discharges: No displacement of population,
housing, businesses, or jobs. No impact on property values
anticipated.
Water Sources and Discharges: No displacement of population,
housing, businesses, or jobs. No impact on property values
anticipated.
Natural Gas Facilities: No displacement of population, housing,
businesses, or jobs. No impact on property values anticipated.
Natural Gas Facilities: No displacement of population, housing,
businesses, or jobs. No impact on property values anticipated.
HVTL Corridors: No displacement of population, housing,
businesses, or jobs. No impact on property values anticipated.
HVTL Corridors: No displacement of population, housing,
businesses, or jobs. No impact on property values anticipated.
2-91
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
General: Project spending and creation of new construction and
operation jobs would provide value added benefits to regional
economy ($3.1 billion over 6 years during construction; $1.1
billion/yr during operation of both phases; the power plant would
be expected to operate commercially for 20 years or more).
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Environmental Justice
No Action
No change in
existing conditions
relative to minority
and low-income
populations; no
potential for
economic benefits
from proposed
project.
West Range
East Range
Power Plant Site: Minority and low-income populations in the
region of influence for the power plant do not exceed 50% of the
population and are not meaningfully greater than the percentages
in the general population. Therefore, the plant site would not have
a disproportionately high and adverse impact on minority or lowincome populations.
Power Plant Site: Minority and low-income populations in the
region of influence for the power plant do not exceed 50% of the
population and are not meaningfully greater than the percentages
in the general population. Therefore, the plant site would not have
a disproportionately high and adverse impact on minority or lowincome populations.
The closest concentrations of American-Indian populations are
located approximately 20 mi from the site. Local tribes expressed
concern regarding health risks associated with project pollutants
and their impact on traditional food sources. However, the
increment of mercury (less than 0.5 percent increase) and other
pollutants from the project would be very low and human health
impacts from fish consumption would be negligible even within 2
mi from the power plant site.
The closest concentrations of American-Indian populations are
located approximately 50 mi from the site. Local tribes expressed
concern regarding health risks associated with project pollutants
and their impact on traditional food sources. However, the
increment of mercury (less than 0.5 percent increase) and other
pollutants from the project would be very low and human health
impacts from fish consumption would be negligible even within 2
mi from the power plant site.
Transportation Facilities, Water Sources and Discharges,
Natural Gas Facilities, HVTL Corridors: No disproportionately
high and adverse impacts on minority or low-income populations
are indicated.
Transportation Facilities, Water Sources and Discharges,
Natural Gas Facilities, HVTL Corridors: No disproportionately
high and adverse impacts on minority or low-income populations
are indicated.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Community Services
2-92
Power Plant Site: Demands by the generating station may
require staff at local fire and emergency response agencies to
increase by 20% or less. Large numbers of construction workers
(>1,500 during 3 years of peak construction) may affect capacities
of local law enforcement agencies. Security requirements for the
generating station may affect capacities of local law enforcement
agencies.
Transportation Facilities: Potential for delays to emergency
response vehicles at 17 rail grade crossings between Grand
Rapids and Taconite (8 in Grand Rapids). Approximately 2.5%
daily probability of delay at a crossing caused by train serving
Mesaba plant; 4% probability of delay from combined rail traffic.
Transportation Facilities: Potential for delays to emergency
response vehicles at 8 rail grade crossings between Clinton
Township and Hoyt Lakes. Approximately 2.5% daily probability of
delay at a crossing caused by train serving Mesaba plant; 5.5%
probability of delay from combined rail traffic.
Water Sources and Discharges: Security requirements for
process water intake facilities may necessitate terminating access
to Canisteo Mine Pit for recreational boating.
Water Sources and Discharges: No displacement of providers or
change in demand on community services.
Natural Gas Facilities: No displacement of providers or change
in demand on community services.
Natural Gas Facilities: No displacement of providers or change
in demand on community services.
HVTL Corridors: No displacement of providers or change in
demand on community services.
HVTL Corridors: No displacement of providers or change in
demand on community services.
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
No change in
existing conditions
relative to
community
services.
Power Plant Site: Demands by the generating station may
require staff at local fire and emergency response agencies to
increase by 30 to 50%. Large numbers of construction workers
(>1,500 during 3 years of peak construction) may affect capacities
of local law enforcement agencies. Security requirements for the
generating station may affect capacities of local law enforcement
agencies.
Utility Systems
No Action
No change in
existing conditions
relating to utilities;
the region would
not benefit from the
additional source of
power from the
Mesaba Energy
Project.
West Range
East Range
Power Plant Site: The project would tie into the existing grid
without service interruptions and would ensure necessary
upgrades to substations and other infrastructure would be installed
to prevent system failures. The project would provide another
source of power for the region that could reduce outages and help
meet future demand.
Transportation Facilities: No expected impacts.
Transportation Facilities: No expected impacts.
Water Sources and Discharges: The Mesaba Energy Project
would not adversely affect sanitary wastewater treatment capacity.
The wastewater collection system in Taconite currently overflows
during heavy rain and high water table events, which may be
worsened by new flow from the West Range Site. This collection
system would need to be redesigned or repaired regardless of the
outcome of this project. During the construction phase of the
project, potable water requirements would exceed the capacity of
the existing Taconite water supply system; however, planned
improvements to the system would provide sufficient supplies.
Otherwise, potable water supplies would be brought to the project
site by truck.
Water Sources and Discharges: The East Range Alternative
would not adversely impact existing potable and sanitary sewer
systems, as both have capacity to serve the project.
Natural Gas Facilities: No impacts on service providers or
capacity expected.
Natural Gas Facilities: No impacts on service providers or
capacity expected.
HVTL Corridors: The project’s proposed utility lines would be
constructed in accordance with all Federal and state regulations,
and would pose no adverse impact on other resources.
HVTL Corridors: The project’s proposed utility lines would be
constructed in accordance with all Federal and state regulations,
and would pose no adverse impact on other resources.
2-93
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Power Plant Site: The project would tie into the existing grid
without service interruptions and would ensure necessary
upgrades to substations and other infrastructure would be
installed to prevent system failures. The project would provide
another source of power for the region that could reduce outages
and help meet future demand.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Traffic and Transportation
No Action
No change in
existing vehicular
traffic; Level of
Service (LOS)
conditions would
remain the same.
Realignment of CR
7 might not occur;
hence, traffic
hazards would
remain at
intersection of CR 7
and US 169.
West Range
East Range
Power Plant Site: During construction: temporary LOS
degradation of US 169 – from a LOS of C to D; however, new CR
7 or proposed improvements at US 169/CR 7 intersection
expected to alleviate traffic congestion and hazards.
Power Plant Site: During construction: temporary LOS
degradation of most of nearby roads; however, lowest LOS would
be B (represents free flow traffic with little congestion).
Reconstruction of Hampshire Drive expected to minimize potential
congestion at intersection of CR 666 and CR 110.
During operation: LOS would remain the same on nearby
roadways, except for CR 7 (south of new Access Road 1), which
would improve from B to A because of new Access Road 1.
During operation: LOS would remain the same on nearby
roadways, except for CR 666 (north of CR 110), which would
degrade from A to B.
Transportation Facilities:
Transportation Facilities:
Rail use during construction and operations is expected to have
minimal adverse impacts to baseline rail traffic conditions.
Rail use during construction and operations is expected to have
minimal adverse impacts to baseline rail traffic conditions.
Access Roads:
• Access Road 1 would improve LOS on CR 7 (south of new
Access Road 1) from level B to level A.
• Access Road 2 would be used by site traffic only and would not
impact LOS.
Access Roads:
• Access Road 1 would provide two access points off of CR 666,
which would minimize impacts to traffic flow during any future
construction or maintenance work on CR 666.
Water Sources and Discharges: Temporary and localized traffic
congestion during construction.
Water Sources and Discharges: Temporary and localized traffic
congestion during construction.
Natural Gas Facilities: Temporary and localized traffic
congestion during construction.
Natural Gas Facilities: Temporary and localized traffic congestion
during construction.
HVTL Corridors: Temporary and localized traffic congestion
during construction.
HVTL Corridors: Temporary and localized traffic congestion
during construction.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
2-94
Materials and Waste Management
No Action
No change in
existing conditions;
no increase in the
risk of a hazardous
waste release.
West Range
East Range
Power Plant Site: Proper handling and storage of materials and
wastes would be conducted to minimize potential for a release of
a hazardous waste or material to the environment. In-state or outof-state solid waste collection services and landfills would have
the capability and capacity to accept solid wastes generated.
Power Plant Site: Proper handling and storage of materials and
wastes would be conducted to minimize potential for a release of a
hazardous waste or material to the environment. In-state or out-ofstate solid waste collection services and landfills would have the
capability and capacity to accept solid wastes generated.
Additional market analysis would be required to secure a market
and avoid disposal of slag (1000-1600 tons per day generated for
both phases); however, sufficient capacity is available if disposal
of the slag is necessary. Commercially available treatment,
stabilization, or disposal for waste streams generated. Generating
Station would be regulated as a large quantity generator of
hazardous waste (sulfuric acid, spent activated carbon and
potentially the ZLD filter cake, as well as smaller quantities of
other hazardous wastes). No substantial increase in risk of a
hazardous waste release to the environment. Proper handling
and storage of wastes in accordance with the Resource
Conservation and Recovery Act (RCRA) would be adhered to.
Additional market analysis would be required to secure a market
and avoid disposal of slag (1000-1600 tons per day generated for
both phases); however, sufficient capacity is available if disposal of
the slag is necessary. Commercially available treatment,
stabilization, or disposal for waste streams generated. Generating
Station would be regulated as a large quantity generator of
hazardous waste (sulfuric acid, spent activated carbon and
potentially the ZLD filter cake, as well as smaller quantities of other
hazardous wastes). No substantial increase in risk of a hazardous
waste release to the environment. Proper handling and storage of
wastes in accordance with RCRA would be adhered to.
Transportation Facilities: Proper handling and storage of
materials and wastes would be conducted to minimize potential
for a release of a hazardous waste or material to the environment.
Water Sources and Discharges: Proper handling and storage of
materials and wastes would be conducted to minimize potential
for a release of a hazardous waste or material to the environment.
HVTL Corridors: Proper handling and storage of materials and
wastes would be conducted to minimize potential for a release of
a hazardous waste or material to the environment.
Transportation Facilities: Proper handling and storage of
materials and wastes would be conducted to minimize potential for
a release of a hazardous waste or material to the environment.
Water Sources and Discharges: Proper handling and storage of
materials and wastes would be conducted to minimize potential for
a release of a hazardous waste or material to the environment.
Natural Gas Facilities: Proper handling and storage of materials
and wastes would be conducted to minimize potential for a release
of a hazardous waste or material to the environment.
HVTL Corridors: Proper handling and storage of materials and
wastes would be conducted to minimize potential for a release of a
hazardous waste or material to the environment.
2-95
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
Natural Gas Facilities: Proper handling and storage of materials
and wastes would be conducted to minimize potential for a
release of a hazardous waste or material to the environment.
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Safety and Health
No Action
No added health
and safety risk, and
no increase in the
probability of
construction or
operational health
and safety risks.
East Range
Power Plant Site: Construction workers would follow a safety
plan and standard safety practices to reduce the potential for
construction-related impacts. During the 5-year construction
period, statistically less than 1 worker fatality (0.4) would occur.
During the operational timeframe of the plant, statistically less
than 1 operations-related worker fatality (0.01) would occur.
Based on air emission modeling results, cancer or morbidity
hazards to workers or to the public would be small and would not
exceed EPA standards. Specifically, the projected acute, subchronic, and chronic non-cancer hazard indices would be 0.5, 0.1,
and 0.03, respectively, compared to a threshold index of 1, and
-07
the projected cancer risk would be 3x10 , compared to a
-05
threshold of 1x10 . Potential major operating accidents or
intentional destructive acts, although not anticipated, could result
in fires and localized airborne releases of toxic substances, such
as CO, H2S, and SO2. In such cases, plant workers would be the
most at-risk of injury or death, although the nearest residents,
located 0.6 to 0.8 mi from the plant, would also be at-risk from a
large release.
Power Plant Site: Construction workers would follow a safety
plan and standard construction safety practices to reduce the
potential for construction-related impacts. During the 5-year
construction period, statistically less than 1 worker fatality (0.4)
would occur. During the operational timeframe of the plant,
statistically less than 1 operations-related worker fatality (0.01)
would occur. Based on air emission modeling results, cancer or
morbidity hazards to workers or to the public would be small and
would not exceed EPA standards. Specifically, the projected
acute, sub-chronic, and chronic non-cancer hazard indices would
be 0.5, 0.1, and 0.03, respectively, compared to a threshold index
-07
of 1, and the projected cancer risk would be 3x10 , compared to
-05
a threshold of 1x10 . Potential major operating accidents or
intentional destructive acts, although not anticipated, could result
in fires and localized airborne releases of toxic substances such as
CO, H2S, and SO2. In such cases, plant workers would be the
most at-risk of injury or death, although the nearest residents,
located 1 mi from the plant, would also be at-risk from a large
release.
Transportation Facilities: During construction and operation, it
is estimated, respectively, that approximately 1.2 and 0.53
fatalities could occur due to the movement of workers and material
via trucks and personal vehicles. Because of the relatively low
incremental addition of project-related train trips (up to one and
two roundtrips per day during Phase I and II, respectively), it is
expected that increases to safety hazards at at-grade crossings
would be low because baseline vehicular traffic numbers within
the region of influence are considered low.
2-96
Water Sources and Discharges: No impacts would be expected.
Transportation Facilities: During construction and operation, it is
estimated, respectively, that approximately 1.2 and 0.53 fatalities
could occur due to the movement of workers and material via
trucks and personal vehicles. Because of the relatively low
incremental addition of project-related train trips (up to one and
two roundtrips per day during Phase I and II, respectively), it is
expected that increases to safety hazards at at-grade crossings
would be low because baseline vehicular traffic numbers within the
region of influence are considered low.
Water Sources and Discharges: No impacts would be expected.
Natural Gas Facilities: No impacts would be expected.
Natural Gas Facilities: No impacts would be expected.
HVTL Corridors: Research regarding the potential for public
health risks from the inhalation of pollutant particles charged by
HVTLs (i.e., the Henshaw Effect) is currently inconclusive.
Therefore, these risks are considered comparable to the risks
imposed by tens of thousands of mi of HVTLs already in use
throughout the U.S. Electromagnetic field (EMF) exposure from
utility lines would fall below the 2-kV/m limit at the edge of the
ROW. There would be no permanent residents located in areas
exceeding 2-kV/m.
HVTL Corridors: Research regarding the potential for public
health risks from the inhalation of pollutant particles charged by
HVTLs (i.e., the Henshaw Effect) is currently inconclusive.
Therefore, these risks are considered comparable to the risks
imposed by tens of thousands of mi of HVTLs already in use
throughout the U.S. EMF exposure from utility lines would fall
below the 2-kV/m limit at the edge of the ROW. There would be
no permanent residents located in areas exceeding 2-kV/m.
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
West Range
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Noise
No Action
East Range
Power Plant Site:
Power Plant Site:
During construction:
Aggregate noise levels at receptors not expected to exceed the
Minnesota Pollution Control Agency (MPCA) daytime threshold of
60 dBA (L50).
During construction:
Steam blows would be an unavoidable adverse impact. A series
of short steam blows, lasting two or three minutes each, would be
performed several times daily over a period of two or three weeks
during the final weeks of construction. Resultant levels at nearby
receptors would range from 88 to 103 dBA; however, steam piping
would be equipped with silencers that would reduce noise levels
by 20 dBA to 30 dBA at each receptor location.
Steam blows would be an unavoidable adverse impact. A series of
short steam blows, lasting two or three minutes each, would be
performed several times daily over a period of two or three weeks
during the final weeks of construction. Resultant sound levels at
nearby receptors would range from 88 to 103 dBA; however, steam
piping would be equipped with silencers that would reduce noise
levels by 20 dBA to 30 dBA at each receptor location.
During operation:
During operation:
Daytime – MPCA noise thresholds would not be exceeded.
Noise levels would not exceed daytime or nighttime MPCA
thresholds. Without mitigation, predicted daytime and nighttime
noise level increases were less than 1.5 dBA, which would not be
detectable at any receptor locations.
Nighttime – Without mitigation, the noise level exceedances
above the L50 threshold would occur at R2 through R5 and would
range from 1.6 dBA (R5) through 3.6 dBA (R4), respectively (R2
through R5 represent residential areas ranging from 3,900 ft to
4,400 ft from the proposed plant site – see Section 3.18 for
receptor location details). The noise levels would exceed the L10
threshold by 3.4 and 1.5 dBA at R3 and R4, respectively. The
greatest predicted increase occurs for the nighttime L10 limit at 3
dBA (at R2 and R5) and for the nighttime L50 limit at 2.7 dBA (at
R2). With the proposed mitigation, it is expected that state noise
standards would be met at all sites, except for the L10 limit at R3
and R4 because the levels are already over the standard due to
their proximities to CR 7. The greatest predicted increase would
occur for the nighttime L10 limit at 3 dBA (at R2 and R5) and for
the nighttime L50 limit at 2.7 dBA (at R2). With the proposed
mitigation, it is expected that any resulting increase in noise levels
from plant operations would not exceed 1 dB, thus would not be
perceived at any of the residential receptor locations.
MPCA residential daytime noise limits of 60 dBA (L50) would be
exceeded at one receptor site by 5 dBA; however, this is not a
residential receptor and the increase would be temporary (during
construction only).
2-97
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
No change in noise
emissions. There
would be no new
violations or
exceedances of
noise standards;
however, residential
noise Receptor 3
(R3) and Receptor
4 (R4) at the West
Range are currently
above the MPCA
noise thresholds.
R3 and R4 are
residential areas
3,900 and 4,400 ft,
respectively, west
of the proposed
plant site (see
Section 3.18 for
noise receptor
details).
West Range
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
Noise
No Action
West Range
East Range
Transportation Facilities:
Transportation Facilities:
Noise levels would range from 57 to 69 dBA at residential
receptors R2 and R5 during rail line construction, but would be
temporary (during construction only) and would be below the
ATPA guideline of 70 dBA.
Incremental rail noise increase may be discernable at residential
noise receptors R1, R2, and R3 (ranging from 800 ft to 9,200 ft
from the proposed plant site), but would be short-term (during
construction only) and below the ATPA guideline of 70 dBA.
Train horns, as required under Federal Railroad Administration
(FRA) regulations would be adverse unavoidable impacts at grade
crossings.
Train horns, as required under FRA regulations, would be adverse
unavoidable impacts at grade crossings.
Access Roads:
There are no residences or sensitive noise receptors in proximity
to the proposed access road intersecting CR 666.
Access Road 1 (new CR 7) would exceed the nighttime L10
threshold at 10 receptor sites (an average decibel increase of
1 dB – 6 dB over and above the threshold of 55 dB) and the
daytime L10 threshold of 65 dBA would be exceeded by 1 dBA at
one receptor. These impacts would be temporary.
Access Roads:
DOE/EIS-0382D
DRAFT ENVIRONMENTAL IMPACT STATEMENT
Table 2.4-1. Summary Comparison of Impacts (Phases I & II)
During operation: All receptor locations would be within the
daytime limits (L50 of 60 dBA).
Water Sources and Discharges: Temporary and localized
increases in noise levels during construction of water pipelines.
Natural Gas Facilities: Temporary and localized increases in
noise levels during construction of natural gas pipelines.
Natural Gas Facilities: Temporary and localized increases in
noise levels during construction of natural gas pipelines.
HVTL Corridors: Temporary and localized increases in noise
levels during construction of HVTLs.
Acronyms: ac – acre(s); alt. – alternative; ATPA – Andean Trade Preferences Act; BMPs – best management practices; BWCAW – Boundary Waters Canoe Area Wilderness;
CAMR – Clean Air Mercury Rule; CMP – Canisteo Mine Pit; CO – carbon monoxide; CO2 – carbon dioxide; CR – County Road; DAT – deposition analysis threshold; dBA – Aweighted decibels; EMF – electromagnetic field; FRA – Federal Railroad Administration; ft – feet; gpd – gallons per day; gpm – gallons per minute; H2S – hydrogen sulfide; HAP –
hazardous air pollutant; HVTL – high voltage transmission line; IGCC – integrated gasification combined cycle; kg – kilogram; kV – kilovolt; LOS – level of service; m – meter; M –
million; MAAQS – Minnesota Ambient Air Quality Standards; mi – mile(s); MPCA – Minnesota Pollution Control Agency; N – nitrogen; NAAQS – National Ambient Air Quality
Standards; NH3 – ammonia; NOx – nitrogen oxides; NPDES – National Pollutant Discharge Elimination System; NPS – National Park Service; NRHP – National Register of Historic
Places; Pb – lead; PM10 – particulate matter (aerodynamic diameter <10 µm); PSD – prevention of significant deterioration; RCRA – Resource Conservation and Recovery Act; ROW
– right-of-way; S – sulfur; SEC – sediment and erosion control; SHPO – State Historic Preservation Office; SO2 – sulfur dioxide; SWPPP – Stormwater Pollution Prevention Plan; tpy
– tons per year; US – U.S. Highway; VNP – Voyageurs National Park; VOCs – volatile organic compounds; yd – yard; yr – year; ZLD – zero liquid discharge
2-98
MESABA ENERGY PROJECT
2. PROPOSED ACTION AND ALTERNATIVES
HVTL Corridors: Temporary and localized increases in noise
levels during construction of HVTLs.
Water Sources and Discharges: Temporary and localized
increases in noise levels during construction of water pipelines.
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