147 Pollution Prevention Opportunities in the

147  Pollution Prevention Opportunities in the
Environmental
Studies
Research
Funds
147
Pollution Prevention
Opportunities in the
Offshore Oil and Gas
Sector - Final Report
October 2003
Pollution Prevention
Opportunities in the
Offshore Oil and Gas Sector
Final Report
March 2004
Environmental Studies
Research Funds
02-0743-0100
Submitted by:
Dillon Consulting Limited
with BMT Cordah
The correct citation for this report is:
Dillon Consulting Limited with DMT Cordah, Pollution Prevention Opportunities in the Offshore Oil
and Gas Sector, Final Report. March 2004. Environmental Studies Research Funds Report No. 147.
Calgary. 73p
The Environmental Studies Research Funds are financed from special levies on the oil and gas industry
and administered by the National Energy Board for the Minister of Natural Resources Canada and the
Minister of Indian Affairs and Northern Development.
The Environmental Studies Research Funds and any person acting on their behalf assume no liability
arising from the use of the information contained in this document. The opinions expressed are those of
the authors and do not necessarily reflect those of the Environmental Studies Research Funds agencies.
The use of trade names or identification of specific products does not constitute an endorsement or
recommendation for use.
Published under the auspices of the
Environmental Studies Research Funds
ISBN 0-921652-58-5
Environmental Studies Research Funds
Pollution Prevention Opportunities
in the Offshore Oil and Gas Sector
March 2004
Executive Summary
Pollution prevention is quickly becoming the preferred approach to protecting and conserving the
environment. Pollution prevention is defined in the Canadian Environmental Protection Act as
“the use of processes, practices, materials, products, substances or energy that avoid or minimize
the creation of pollutants and waste and reduce the overall risk to the environment or human
health”. This includes waste reduction through: process redesign or modification; substitution;
in-process recycling; improved maintenance; and administrative/corporate culture modifications.
This document is a review of pollution prevention practices and opportunities for offshore oil
and gas activities in Atlantic Canada. The purpose of the report is to provide guidance to
operators in applying pollution prevention to projects. It focuses on pollution prevention
opportunities for five priority aspects of offshore operations as identified by ESRF East Coast
Waste/Discharges Technical Advisory Group (TAG): air emissions; drilling muds and cuttings;
produced water; biocides and glycol.
The document identifies current practices already followed or designed into projects that are
pollution prevention practice and future opportunities that may become technologically and
economically feasible in the offshore environment in Atlantic Canada as the technologies
develop.
The five focus topics are addressed separately for ease of reference but this approach is not
consistent with the strategy of holistic application of pollution prevention. In making project
decisions about management of drilling muds, for instance, energy consumption, air emissions,
vessel requirements, potential environmental effects of discharges and health and safety risks all
may have relevance to the type of drilling fluids used. As a result, examples and case studies that
have implications across more than one of these topics are provided.
Pollution prevention is a re-thinking of the source of pollution, best applied at conception of an
undertaking and during design, when it is possible to consider whether an activity or process is
necessary to meet the objective of the undertaking and a process can be optimized or redesigned
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to reduce or eliminate the need for a toxic substance or reduce the amount of energy required.
Examples of pollution prevention planning techniques include: “Green” design and
reformulation, also known as Design for Environment (DfE) or Cleaner Production (CP); process
improvements and equipment modifications; materials or chemical substitution; inventory
control; corporate culture and employee training; on-site re-use; and preventive maintenance.
Costs and benefits in pollution prevention projects should be evaluated for a sufficiently long
period to capture the long-term benefits offered by many projects. Pollution prevention projects
may also offer significant savings in the areas of compliance, waste disposal and insurance.
Therefore when evaluating pollution prevention opportunities costs such as environmental
compliance costs and oversight or management costs should be taken into account along with
capital costs and operating costs. As well consideration should be given to: improved public
image; improved productivity; decreased environmental liability; improved environmental and
health quality; potential market opportunity (e.g., marketable by-products); and access to capital.
The document provides a number pollution prevention opportunities for consideration including:
•
Avoidance of well testing of initial exploration wells, which will reduce flaring.
•
Changes in power generation or selection of power generation methods that have the
potential to be more efficient such as substitution of diesel with natural gas or condensate.
•
Use of ignition systems that operate in any weather conditions to eliminate the need for a
pilot flare.
•
The use of low NOx turbines, also referred to as Dry Low Emissions (DLE) turbines,
however, there are trade-offs with the technology (e.g., increased fugitive and CO2
emissions).
•
Sequester CO2 through re-injection.
•
The use of jetting instead of drilling, if suitable unconsolidated overburden or soft rock is
present to reduce use of drilling muds.
•
Re-injection of muds and cuttings.
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•
The use of synthetic-based mud (SBM) or enhanced mineral oil-based mud (EMOBM)
reduces the diameter of wells drilled and, consequently, the volume of muds used and
cuttings produced. It also reduces drilling time and associated emissions.
•
To reduce drilling muds, the concept of slim hole technology applies the design of drilling
programs with the minimum diameter necessary to complete the well. Also expandable
casings have been used experimentally to drill wells.
•
Re-injection of produced water into source or depleted reservoir.
•
Downhole separation of oil and water and gas and water. Separation is also possible at the
seafloor. The produced water must then be re-injected.
•
Hydrocycloning of produced water using condensate to separate hydrocarbons from
produced water.
•
Where practical, alternative biocides may be used to substitute less toxic substances for those
currently used.
•
Monitoring of chlorine levels to adjust chlorine additions.
•
Installation of electrolytic systems using copper and aluminum or iron anodes to replace
biocides and chlorine.
•
Options for pollution prevention for monoethylene glycol (MEG) are limited, however,
propriety systems are available.
•
Emerging technologies include the use of anti-agglomerates and kinetic inhibitors to prevent
hydrate formation.
Pollution prevention includes the holistic consideration of the design of a project. The use of
project design workshops can be used to broadly evaluate development options in a nonjudgmental, inclusive environment.
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Résumé
La prévention de la pollution est rapidement en train de devenir l’approche préférée pour
protéger et conserver l’environnement. Dans la Loi canadienne sur la protection de
l’environnement, elle est définie comme « l’utilisation de processus, de pratiques, de matériaux,
de produits ou de sources d’énergie qui évitent ou réduisent au minimum la création de polluants
et de déchets et qui diminuent les risques pour la santé humaine ou l’environnement ». Cela
comprend la réduction des déchets par la reconception ou la modification des processus; la
substitution; le recyclage en cours de traitement; l’amélioration de l’entretien; et des
changements dans la culture administrative/organisationnelle.
Le présent document est un examen des pratiques et des occasions de prévention de la pollution
pour l’exploration pétrolière et gazière en mer dans le Canada atlantique. Il a pour but de guider
les exploitants dans l’application de mesures de prévention de la pollution aux projets, et se
concentre sur les possibilités de prévention de la pollution pour cinq aspects prioritaires des
activités en mer identifiés par le Groupe consultatif technique (GCT) sur les déchets (rejets sur la
côte Est du FEE : les émissions dans l’atmosphère, les boues et les déblais de forage, l’eau
produite, les biocides et le glycol.
Le document fait état des pratiques de prévention de la pollution déjà appliquées ou incorporées
à des projets, et des possibilités futures qui pourraient devenir technologiquement et
économiquement faisables dans les zones extracôtières du Canada atlantique à mesure que les
technologies se développeront.
Les cinq domaines prioritaires sont examinés séparément par souci de commodité, mais cette
approche ne concorde pas avec la stratégie d’application globale des mesures de prévention de la
pollution. Par exemple, dans le cadre des décisions de gestion des boues de forage dans un
projet, la consommation d’énergie, les émissions dans l’atmosphère, les exigences concernant les
navires, les effets potentiels sur l’environnement des rejets et les risques pour la santé et la
sécurité sont tous des éléments qui peuvent dépendre du type de fluide de forage utilisé. C’est
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pourquoi on fournit des exemples et des études de cas ayant des implications pour plusieurs de
ces éléments.
La prévention de la pollution est un réexamen de la source de pollution qu’il est préférable
d’effectuer au moment de la conception et durant l’élaboration d’une entreprise, quand il est
possible d’examiner si une activité ou un procédé est nécessaire pour atteindre l’objectif de
l’entreprise, et si un procédé peut être optimisé ou modifié pour réduire ou éliminer l’utilisation
d’une substance toxique ou réduire la quantité d’énergie requise. Parmi les techniques de
planification pour prévenir la pollution figurent les suivantes : la conception et la reformulation
« vertes », également appelées conception écologique ou production moins polluante,
l’amélioration des procédés et la modification de l’équipement, le recours à d’autres matériaux
ou substances chimiques, le contrôle des stocks, la culture organisationnelle et la formation des
employés, la réutilisation sur place, et l’entretien préventif.
Dans les projets de prévention de la pollution, les coûts et les avantages devraient être évalués
sur une période suffisamment longue pour qu’on puisse saisir les avantages à long terme offerts
par de nombreux projets. Ces projets peuvent également autoriser des économies importantes
dans les domaines de la conformité, de l’élimination des déchets et de l’assurance. Par
conséquent, au moment d’évaluer les possibilités de prévention de la pollution, il faudrait tenir
compte de coûts comme les coûts de conformité environnementale et les coûts de surveillance ou
de gestion, de même que des coûts d’immobilisation et d’exploitation. Il faudrait également
prendre en considération l’amélioration de l’image publique, l’augmentation de la productivité,
la réduction des responsabilités environnementales, l’amélioration de la qualité de
l’environnement et de la santé, les possibilités de marchés (p. ex., produits commercialisables), et
l’accès au capital.
Le document présente un certain nombre de possibilités de prévention de la pollution à examiner,
dont :
•
L’élimination des essais de puits d’exploration, ce qui réduira le torchage.
•
Le changement de méthodes de production d’électricité ou le choix de méthodes qui peuvent
être plus efficaces, comme de remplacer le combustible diesel par le gaz naturel ou un
condensat.
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•
L’utilisation de systèmes d’allumage pouvant fonctionner dans toutes les conditions
climatiques afin d’éliminer les veilleuses.
•
L’utilisation de turbines à faibles émissions de NOx, également appelées turbines à faibles
émissions sèches; il y a toutefois un prix à payer pour cette technologie (p. ex. augmentation
des émissions fugitives et des émissions de CO2).
•
La séquestration du CO2 par réinjection.
•
L’utilisation du fonçage au jet d’eau au lieu du forage dans les roches de recouvrement ou les
roches tendres appropriées afin de réduire l’utilisation de boue de forage.
•
La réinjection des boues et des déblais.
•
L’utilisation de boues synthétiques ou de boues à base d’huile minérale réduit le diamètre des
puits de forage et, par conséquent, le volume des boues utilisées et des déblais produits. Ce
remplacement réduit également le temps de forage et les émissions connexes.
•
Pour réduire les boues de forage, le filiforage permet de réaliser le forage d’un puits en
n’utilisant que le diamètre minimum nécessaire. On a également utilisé expérimentalement
des cuvelages extensibles pour le forage des puits.
•
La réinjection de l’eau produite dans une source ou un réservoir épuisé.
•
Séparation dans le puits du pétrole et de l’eau ainsi que du gaz et de l’eau. La séparation est
également possible sur le plancher océanique. L’eau produite doit alors être réinjectée.
•
L’hydrocyclonage de l’eau produite au moyen d’un condensat pour séparer les hydrocarbures
de l’eau produite.
•
Dans la mesure du possible, on peut utiliser des biocides moins toxiques pour remplacer ceux
présentement utilisés.
•
La surveillance de la concentration de chlore pour en régler les ajouts.
•
L’installation de systèmes d’électrolyse utilisant des anodes de cuivre et d’aluminium ou de
fer pour remplacer les biocides et le chlore.
•
Les options de prévention de la pollution pour l’éthylèneglycol sont limitées, mais des
systèmes brevetés sont disponibles.
•
Les nouvelles technologies comprennent l’utilisation d’anti-agglomérats et d’inhibiteurs
cinétiques pour empêcher la formation d’hydrates.
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La prévention de la pollution implique la prise en considération de la conception du projet dans
son ensemble. Les ateliers de conception de projets peuvent être utilisés pour évaluer les options
de développement générales dans un environnement inclusif et sans préjugés.
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Acknowledgements
Dillon Consulting Limited gratefully acknowledges the assistance of those in the oil and gas
industry who gave their time to discuss pollution prevention within Atlantic Canada. Industry has
been supportive of the project and has implemented a proactive approach to pollution prevention
and anticipates its further incorporation in current and future projects.
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Table of Contents
Page
1.0
Introduction ..............................................................................................1
1.1
1.2
1.3
1.4
1.5
1.6
2.0
Pollution Prevention Priority Topics ............................................... 20
2.1
2.2
2.3
2.4
2.5
3.0
Definition and Legal Context...................................................................................2
Structure and Use of This Document.......................................................................3
Pollution Prevention and the Offshore Waste Treatment Guidelines......................5
Pollution Prevention and Environmental Management Systems.............................7
Pollution Prevention Techniques .............................................................................7
Pollution Prevention Planning ...............................................................................14
Air Emissions.........................................................................................................20
2.1.1 Background ............................................................................................... 20
2.1.2 Current Practice ....................................................................................... 22
2.1.3 Pollution Prevention Opportunities.......................................................... 23
Drilling Fluids and Drill Cuttings ..........................................................................25
2.2.1 Background ............................................................................................... 25
2.2.2 Current Practice ....................................................................................... 28
2.2.3 Pollution Prevention Opportunities.......................................................... 29
2.2.4 Future Pollution Prevention Opportunities .............................................. 33
Produced Water......................................................................................................34
2.3.1 Background ............................................................................................... 34
2.3.2 Current Practices...................................................................................... 35
2.3.3 Pollution Prevention Opportunities.......................................................... 35
Biocides..................................................................................................................38
2.4.1 Background ............................................................................................... 38
2.4.2 Current Practice ....................................................................................... 39
2.4.3 Pollution Prevention Opportunities.......................................................... 39
MEG.......................................................................................................................40
2.5.1 Background ............................................................................................... 40
2.5.2 Current Practice ....................................................................................... 41
2.5.3 Pollution Prevention Opportunities.......................................................... 41
Other Opportunities, Examples and Case Studies ......................... 43
3.1
3.2
3.3
Slender Well...........................................................................................................43
Expandable Casings ...............................................................................................44
Mud and Cuttings Disposal....................................................................................44
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3.4
3.5
3.6
3.7
3.8
3.9
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Discharge of SBM Cuttings with Retained Oil to Sea as a Pollution
Prevention Measure ...............................................................................................45
Hydrate Control .....................................................................................................46
Natural Gas STAR .................................................................................................47
Produced Water......................................................................................................49
Carbon Dioxide Injection and Sequestration .........................................................49
Design Approaches ................................................................................................50
Information Sources ............................................................................. 51
4.1
4.2
4.3
4.4
References..............................................................................................................51
Additional Resource Documents ...........................................................................57
Additional Web Resources ....................................................................................58
Contact Information for Organizations Consulted in Preparing the Document ....59
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List of Figures:
Figure 1-1
Environmental Protection Hierarchy (Environment Canada, 2001)....................... 8
List of Tables:
Table 1-1
Table 1-2
Table 1-3
Table 1-4
Table 2-1
The Environmental Protection Hierarchy (Environment Canada, 2003).............. 13
Environmental Management Measures that are Pollution Prevention
and are Not (adapted from Box 1 and Box 2 of Ontario, 1993) ........................... 14
Pollution Prevention Planning Checklist (Environment Canada, 2001)............... 15
Possible Pollution Prevention Objectives and Practices
(adapted from Table 2, p. 15, Environment Canada, 2001).................................. 17
Worldwide Activities Relating to Drill Cuttings Disposal ................................... 31
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Introduction
Pollution prevention is quickly becoming the preferred approach to protecting and conserving the
environment. Pollution prevention in the Canadian context includes waste reduction through:
process redesign or modification; substitution; in-process recycling; improved maintenance; and
administrative/corporate culture modifications. As the principles, techniques and benefits of
pollution prevention become more broadly known and concepts such as whole-system
engineering are embraced in the industrial and commercial fields, new opportunities will become
apparent more and more pollution prevention initiatives will take place.
This document is a review of pollution prevention, as defined in Section 1.1, and pollution
prevention practices and opportunities for offshore oil and gas activities in Atlantic Canada. The
purpose of the report is to provide guidance to operators in applying pollution prevention to
projects. Pollution prevention was incorporated within the Offshore Waste Treatment Guidelines
(NEB et al., 2002) for the first time in the 2002 revisions. Operators need to provide pollution
prevention plans with a drilling program authorization (DPA) or a production operations
authorization (POA) when following the Offshore Waste Treatment Guidelines (OWTG).
One of the themes of this document is the identification of current practices already followed or
designed into projects that are pollution prevention practice. There are also opportunities
identified to replace current practices that may be good environmental management but are not
pollution prevention. Future opportunities are also identified, which may become technologically
and economically feasible in the offshore environment in Atlantic Canada as the technologies
develop.
Revisions
This document is intended to be a living document that will be formally updated concurrent with
the 5-year review cycle for the OWTG. In between the formal updates, the Boards (Canada-Nova
Scotia Offshore Petroleum Board and Canada-Newfoundland Offshore Petroleum Board) should
consider posting pollution prevention initiatives and updates to the document on the Boards’
websites. An email notification alerting interested parties of recent postings will also help to
disseminate new information.
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Definition and Legal Context
Pollution prevention is the central theme of the 1999 Canadian Environmental Protection Act.
The Act defines pollution prevention as “the use of processes, practices, materials, products,
substances or energy that avoid or minimize the creation of pollutants and waste and reduce the
overall risk to the environment or human health”. The Act also refers to pollution prevention
plans, allowing the Federal government to require the development and implementation of
pollution prevention plans for specific toxic substances (for example, acrylonitrile and
dichloromethane). Environment Canada through the National Office of Pollution Prevention and
its regional equivalents provide advice on pollution prevention for government, business and
individuals.
The Canadian definition of pollution prevention should take precedence in application to the
offshore oil and gas sector in Atlantic Canada. Multi-national companies operating in the
offshore oil and gas sector have developed corporate pollution prevention strategies based on
definitions such as those of the US EPA or the international standard of ISO 14000 series.
Therefore these definitions are presented here as context.
Following passage of the Pollution Prevention Act of 1990, the US Environmental Protection
Agency developed a formal definition of pollution prevention and a strategy for making
pollution prevention a central guiding mission. The US definition of pollution prevention means
source reduction but also other practices that reduce or eliminate the creation of pollutants
through (1) increased efficiency in the use of raw materials, energy, water, or other resources or
(2) protection of natural resources by conservation. While this is similar to the Canadian
definition, it does not provide an emphasis on reductions in the use of toxic substances.
ISO 14001:1996 specifies requirements for environmental management systems, to enable an
organization to formulate a policy and objectives taking into account significant environmental
impacts. ISO 14001 requires top management to define the organization’s environmental policy
ensuring, among others, that there is a commitment by top management to “prevention of
pollution”. Thus prevention of pollution becomes one of three pillars of the standard. The other
two are compliance to regulations and continual improvement. ISO 14001’s definition of
prevention of pollution is similar to those given above being the “use of processes, practices,
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materials or products that avoid, reduce or control pollution, which may include recycling,
treatment, process changes, control mechanisms, efficient use of resources and material
substitution”. This definition varies from the Canadian definition in several important factors.
Recycling off-site, treatment or most control mechanisms are not included within pollution
prevention in Canada.
In addition to Canadian Federal initiatives through the Canadian Environmental Protection Act,
activities are taking place at the provincial level. For instance, in the Alberta Leaders
Environmental Approval Document Program (which provides an alternative regulatory
framework for dealing with industrial activities), one of the entry criteria is a pollution
prevention or continuous improvement plan. The Province of Nova Scotia has a web site devoted
to pollution prevention (NSDEL). Through this web site the Department of Environment and
Labour provides free information and technical assistance to business, industry, government and
the public on how to develop and implement programs to prevent pollution. Nova-Scotia has
adopted the Canadian Council of Ministers of the Environment (CCME) definition of pollution
prevention as: "...the use of processes, practices, materials, products or energy that avoid or
minimize the creation of pollutants and wastes, at the source." The web site has a specific
section dealing with pollution prevention in business and industry.
Additional web based information sources are provided with References in this document.
1.2
Structure and Use of This Document
This document focuses on pollution prevention opportunities for five priority aspects of offshore
operations as identified by ESRF East Coast Waste/Discharges Technical Advisory Group
(TAG): air emissions; drilling muds and cuttings; produced water; biocides and glycol. Produced
water and glycol are relevant almost exclusively to production projects. Drilling muds and
cuttings are only related to exploration and development projects. Biocides and air emissions are
relevant to all projects.
For each of these topics there is a separate section that provides a summary description of the
industry aspects relevant to the topic. Sources of wastes and the reasons these are a concern are
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identified. Current conditions and practices in Atlantic Canada are discussed in relation to
alternative approaches. Where there are available or developing alternative practices or methods
that may be applicable as pollution prevention, these are presented. There are pollution
prevention practices now in use that were impractical or not applied until recently. These are
identified and provide a context for the identification of new methods that are in development or
are used elsewhere and may be suitable for use in the harsh conditions of Atlantic Canada in the
future.
Addressing the five focus topics separately and in isolation of each other is not consistent with
the strategy of the holistic application of pollution prevention. In making project decisions about
management of drilling, for instance, the energy consumption, air emissions, vessel
requirements, potential environmental effects of discharges and health and safety risks all may
have relevance to the type of drilling fluids used. Therefore in addition to the separate
presentation of the five focus topics, examples and case studies that have implications across
more than one of these topics are provided separately. Some of these also highlight recent
successes and expected future opportunities in pollution prevention.
Pollution prevention is not a static process. Continuous improvement is fundamental to pollution
prevention practice. Many opportunities for continuous improvement are likely to become
available to the offshore oil and gas industry through new technology. A number of these are
highlighted in this document. For example, expandable tubing has recently been taken from a
technical solution for localized drilling problems to an experimental method for cased well
sections in deep water. This offers considerable pollution prevention benefits as well as cost
savings. When the use of expandable tubing will be practical in Atlantic Canada is not known.
The intent is for this to be a living document that will be revised and updated with new pollution
prevention information as experience and technical advances make new methods available.
Rather than creating a guideline for pollution prevention, the intent is to develop a functional
handbook with an outline of pollution prevention practices in general, examples of current
practices and signposts for opportunities that may become available.
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Inclusion of the information sources is both to provide the reference sources for examples of
current practice in Atlantic Canada and to encourage operators, individually and in cooperation,
to find effective and innovative pollution prevention solutions.
1.3
Pollution Prevention and the Offshore Waste
Treatment Guidelines
The Offshore Waste Treatment Guidelines (NEB et al., 2002) provide practices and standards for
petroleum drilling and production projects for the treatment and disposal of wastes as well as
sampling and analysis of waste streams to ensure compliance. Each application for a drilling
program authorization (DPA) or a production operations authorization (POA) must demonstrate
how the operator will meet the guidelines with compliance monitoring and waste management
programs. Although specified concentrations of waste discharges are achievable using proven
and practicable best available waste treatment technology, the assessment and development of
new technologies are encouraged to reduce the amount of substances discharged.
Operators are expected to minimize the volumes of wastes produced and the quantity of
substances of potential environmental concern contained in the wastes of potential environmental
concern as well as to reduce the toxicity of substances used. Each DPA or POA should describe
the operator’s specific pollution prevention plans to reduce waste generation and discharge. The
plans should include monitoring the progress of waste reduction plans and at least annual
reporting.
Addressing the materials substitution approach to pollution prevention, operators are expected to
evaluate chemicals that are used following the Guidelines Respecting the Selection of Chemicals
Intended to be Used in Conjunction with Offshore Drilling and Production Activities in Frontier
Lands (NEB et al., 1999). These guidelines suggest a management system to assist in the process
of selecting the most environmentally appropriate chemical substances to use. However,
regulatory acceptance of the discharge of substances selected through the guideline process is not
automatic.
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In sections of the OWTG that address specific waste streams there are objectives that are
consistent with the pollution prevention approach, and operators are cautioned that meeting
minimum standards for treatment and disposal of waste streams is not necessarily sufficient to
meet the expectations of pollution prevention.
Air Emissions
Under air emissions, production operators are expected to provide as part of the DPA an estimate
of annual emissions of greenhouse gases (GHG) with plans to control and reduce the emissions.
Annual calculations of GHG should be submitted to the relevant offshore board in accordance
with the Global Climate Change Voluntary Challenge Guide (CAPP, 2000). Volatile organic
compounds (VOC) emissions should be determined and reported for each drilling or production
installation. VOC reporting should be in accordance with existing best management practices for
oil and gas operations in Canada.
Produced Water
Relative to produced water, production operators are expected to include in the DPA an
examination of the feasibility of alternatives to marine discharge of produced water. During
operations this is to be re-examined and reported every five years.
Drilling Muds
For drilling muds the OWTG recommend the minimization of the discharge of oil to the marine
environment and the use of water based muds (WBM) or synthetic based muds (SBM). Oil based
mud (OBM) use would only be approved by exception where WBM or SBM use is not
technically feasible. Enhanced mineral oil-based muds (EMOBM, also called low-toxicity
mineral oil [LTMO]) may be approved if the environmental performance is equivalent to or
better than that of an SBM.
Whole SBM or EMOBM cannot be discharged to sea. The OWTG recommends that remaining
muds of these types be: recovered and recycled; reinjected downhole; or transferred to shore for
approved disposal. Although spent WBM can be marine discharged without treatment, operators
are expected to reduce the need for bulk disposal of these muds.
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For the use of SBM or EMOBM in development drilling, operators are expected to report on the
technical feasibility of re-injection of drill cuttings. Where such re-injection is not technically or
economically feasible, marine discharge of solids may be approved with retained oil on cuttings
amounts achievable with best available technology.
Specific guidelines are provided in the OWTG (NEB et al., 2002). A tabular summary, which is
attached as Appendix A, has also been compiled by Taylor (2002).
1.4
Pollution Prevention and Environmental
Management Systems
An ISO 14001 compliant Environmental Management System is the ideal vehicle for promoting
pollution prevention.
At the policy stage, the commitment by top management to compliance, pollution prevention and
continual improvement ensures that pollution prevention activities are given a high visibility in
the organization.
At the aspects identification stage, priorities will be assigned such that significant aspects are
highlighted and actions taken to improve these aspects. Objectives and targets are set with a view
to preventing pollution, and subsequently management programs ensure that adequate resources
are assigned to carry out the projects. Monitoring, measurement and auditing confirm that the
projects meet the objectives that were set.
1.5
Pollution Prevention Techniques
Pollution prevention is a re-thinking of the source of pollution, best applied at the conception of
an undertaking, when it is possible to consider whether an activity or process is necessary to
meet the objective of the undertaking and a process can be optimized or redesigned to reduce or
eliminate the need for a toxic substance or reduce the amount of energy required. In its simplest
form, pollution prevention is roughly synonymous with source reduction, reducing the
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generation and toxicity of wastes or contaminants at their sources, and thereby reducing releases
to the environment that could pose hazards to the environment and public health. Strictly
speaking, recycling outside of a process stream is not a form of prevention (although ISO 14001
specifically mentions recycling as a pollution prevention activity). The EPA in particular has
held fast to a stricter interpretation because wastes that are recycled have not been prevented.
Figure 1-1
Environmental Protection Hierarchy
(Environment Canada, 2001)
The protection of the environment can
be thought of as a hierarchy of activities
POLLUTION PREVENTION
that are the exact reverse of the way
REUSE
RECYCLE
things used to be done. The new
hierarchy, as presented in Figure 1.1, is
POLLUTION CONTROL
thus prevention as a first initiative (i.e.,
the zero emission concept that is
DISPOSAL
achieved from project conception
through initial design), full life cycle
REMEDIATION
optimization and operation, source
reduction and on-site reuse, followed by
recycling, control (i.e., treatment and
disposal) and finally remediation as the
least desirable step. In the past,
emissions were essentially uncontrolled and, when required, remediation activities were carried
out. More recently, industries concentrated on end of the pipe treatment. Industries are now
realizing that these are costly and unnecessary steps and are investing in zero emissions factories
or as near as they can get to zero emissions by implementing pollution prevention thereby
managing emissions/discharges further up in the process. This is pollution prevention at work. A
useful conception of the new hierarchy is to re-think of waste as a product that has been paid for
but cannot be sold.
Pollution prevention plans form the basis of the pollution prevention process. These plans are
used to systematically identify all available options. Processes are analyzed in order to focus on
the root causes of pollution thus allowing for the identification of the most suitable solution.
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Many techniques can be used depending on the pollution source; some of these techniques
include:
“Green” design and reformulation; also known as Design for Environment (DfE) or
Cleaner Production (CP)
This is probably the most effective technique, because pollution can be “designed” out or
a product reformulated to use less toxic chemicals. This also includes design using a
whole-system approach or whole-system engineering that takes into account both capital
costs and resulting operational costs/benefits.
Process improvements and equipment modifications
Existing processes can be redesigned to consume less energy, use less water, produce
fewer rejects and wastes.
Materials substitution
Similar to product reformulation, materials substitution involves the use of materials or
feedstock that are less polluting.
Inventory control
“Green” purchasing policies help achieve significant waste reduction. Reducing
packaging, using returnable packaging and returning unused products to suppliers help to
reduce pollution.
Corporate culture and employee training
Management commits to creating and supporting corporate initiatives to reduce waste
through, for example, ISO 14001. Training helps to change wasteful habits and education
promotes environmental awareness in employees, suppliers and clients.
On site re-use
Reusing water contaminated by a process into another less sensitive process, internally
recycling scrap, filtering rather than replacing lubricants; re-using solvents for less
rigorous needs before distilling solvents are all techniques that reduce wastes and
pollution.
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Preventive maintenance
Effective maintenance programs help reduce energy consumption, improve operating
efficiencies and reduce the generation of rejects and wastes.
Costs and Benefits of Pollution Prevention
Pollution prevention can save money on the costs involved in an industrial process. Many
pollution prevention opportunities actually cost little money, being more behavioral change
projects than technical projects e.g., training; others must be analyzed carefully to measure their
profitability. Other opportunities may have initial capital or implementation costs but these costs
may result in longer term saving, such as reduced energy costs that in time will offset the initial
cost.
Project plans are usually evaluated on the basis of capital costs, and operating costs such as
utilities and materials. Pollution prevention projects may also offer significant savings in the
areas of compliance, waste disposal and insurance. Neglecting to account for these hidden costs
and savings may lead to the rejection of a perfectly viable project.
The following financial variables should be considered:
Usual costs
Depreciable capital (Equipment, site preparation, installation)
Operating expenses (Direct labour, raw materials, supplies, utilities, maintenance)
Operating revenues including by-products
Compliance costs
Receiving area (spill response equipment, emergency plans)
Raw materials storage (storage facilities, secondary containment, reporting and reports)
Process area (emissions control equipment, safety equipment, waste collection
equipment)
Solid and hazardous waste (personnel training and certification; disposal fees, storage
areas, transportation fees)
Air and water emissions control (capital costs, operating expenses, discharge fees,
permits)
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Oversight costs
Purchasing (inventory control, product/vendor research, regulatory impact analysis)
Engineering (hazard analysis, sampling and testing)
Production (rework, disposal management, training, medical monitoring, inspection and
audits)
Marketing (public relations)
Management (penalties and fines, legal fees, information systems, insurance)
Finance (credit costs, tied-up capital)
Apart from the beneficial effects to the bottom line, pollution prevention has many other
benefits:
Improved public image
Consumers view more favorably businesses that adopt pollution prevention strategies.
Improved productivity
Pollution prevention plans help organizations identify opportunities to decrease raw
material usage, eliminate unnecessary operations, maximize throughput, reduce off-spec
material, reduce waste and other inefficiencies and improve yields.
Decreased liability
Organizations that substitute toxic materials with safer alternatives reduce the liability
and high costs associated with an unsafe environment.
Improved environmental and health quality
Pollution prevention projects will contribute to reducing the air, water and land pollution
that results from waste generation, treatment and disposal and reduce worker health and
safety risks.
Other Potential Benefits
Market expansion/retention, supply chain compliance, access to capital.
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Costs and benefits in pollution prevention projects should be evaluated for a sufficiently long
period to capture the long-term benefits offered by many projects. It is important to consider all
costs and to evaluate the current cost of the project’s components and their alternative costs.
Each pollution prevention option considered may be evaluated using a variety of tools. The range
of these includes conventional cost accounting, and full cost accounting. A description of these
and their application is provided in the Pollution Prevention Planning Handbook (Environment
Canada, 2001). The web site for the associated tutorial can be found at
http://www.ec.gc.ca/NOPP/P2TUT/eg/indexe.html.
Environmental Protection Hierarchy
Environment Canada states that pollution prevention measures are the upper levels of an
environmental protection hierarchy. Table 1-1 provides more detail than the basic hierarchy
presented in Figure 1-1 as well as brief examples. Environmental protection activities are ordered
from those closest to the root causes of pollution. Product or service changes are given the
highest priority; reuse or recycling are given the lowest priority as pollution prevention activities
if the recycling is on-site. Off-site recycling is considered a higher priority environmental
protection activity, but is not considered as pollution prevention.
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ACTIVITY
Product or Service Changes
Product or Service Improvements
Process or Technology Improvements
Closer to the root causes of pollution
→
Input or Raw Material Changes
Operating Improvements
Reuse or Recycling
(possibly preceded by control or
containment*)
Reuse or Recycling
(possibly preceded by control or
containment*)
Waste-to-Energy
EXAMPLE
Replace environmentally-harmful product/service with
environmentally-responsible product/service
Redesign or reformulate product/service to make more
environmentally-responsible throughout life cycle
e.g., extend product life, design for reuse.
Redesign process or change technology, to make more
efficient use of materials or to avoid/minimize generation of
pollutants/waste
Minimize raw material use
Minimize water use
Minimize energy use
Change purchasing practices/specifications to substitute
environmentally-preferable materials (including less toxic
substances)
Optimize operating efficiency, scheduling
Improve maintenance procedures
Change inventory/purchasing practices to reduce waste
Improve housekeeping practices
Avoid/minimize losses/leaks/spills
On-site reuse materials
Close process loops
Recycle materials on-site
Off-site reuse of waste/by-product materials
Waste exchange
Off-site recycling, reprocessing, material recovery,
reclamation
Combustion of wastes/by-products for energy value, e.g.,
municipal waste incineration, landfill gas power generation
Treatment or Destruction
(possibly preceded by control or
containment*)
Biological treatment, including municipal sewage treatment
Physical treatment
Chemical treatment, e.g., neutralization, stabilization
Disposal (possibly preceded by control or
containment*)
Reclamation or Mitigation
Secure disposal, storage, encapsulation
Landfill
Site/soil remediation
Ecosystem restoration
Impact mitigation, increased health care requirements
Pollution prevention as defined in Canadian policy
and law
The Environmental Protection Hierarchy (Environment Canada, 2003)
Traditional pollution control and
waste management
Table 1-1
March 2004
*e.g., precipitation, scrubbing, baghouses, cycloning, screening, settling, filtration, dewatering, berming, shrouding, sumps, on-site
spill cleanup, etc.
An Ontario pollution prevention planning guidance document gives examples of process changes
considered to be pollution prevention, because the changes reduce the amount of waste created
during production, and provides a contrasting list of measures that are not pollution prevention,
because they are applied after waste is created (Table 1-2).
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Table 1-2
Environmental Management Measures that are and are Not Pollution Prevention
(adapted from Box 1 and Box 2 of Ontario, 1993)
Pollution Prevention Process Changes
On-site Reuse – closed loop recycling reduces
material use and waste production
Input Material Changes – replacement of toxic
process materials with less toxic ingredients;
purchase additives without trace quantities of
hazardous or toxic impurities
Technology Changes – redesign of equipment
such as piping to reduce the volume of material
contained; install hard piped vapour recovery;
use more efficient motors
Best Management Practices – train operators;
separate waste streams to avoid cross
contamination; track shelf life and manage
inventory to avoid unnecessary disposal; turn off
equipment and lighting when not in use; spill and
leak prevention
1.6
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Measures that are Not Pollution Prevention
Off-site Recycling – likely to be more residual waste
than with on-site reuse; likely to be more releases to
the environment during transportation and may be
added exposure risks for workers
Waste Treatment – changes in form or composition of
wastes to reduce or eliminate the amount, toxicity or
disposal space requirements, e.g. incineration or
stabilization
Concentrating Hazardous or Toxic Constituents to
Reduce Volume – dewatering of sludge before
disposal to reduce disposal volume
Diluting Constituents to Reduce Hazard or Toxicity –
the absolute amounts entering the environment are not
reduced
Transferring Hazardous or Toxic Constituents from
One Environmental Medium to Another – collection of
pollutants from one medium and discharging them in
another, for instance activated carbon removal of
solvents from water followed by air emission of the
solvents by regenerating the filter medium
Pollution Prevention Planning
Pollution prevention is primarily implemented through rethinking a project from its inception.
More effective protection of the environment is linked to lower production costs and increased
efficiencies. Increased productivity may be achieved through more efficient materials and energy
use. Pollution prevention may also reduce long-term liabilities from discharges or disposal of
wastes; reduce the risk of accidental spills and discharges to the environment; and reduce
occupational health and safety risks. This summary of pollution prevention planning is primarily
drawn from the Pollution Prevention Planning Handbook (Environment Canada, 2001) and is
closely akin to the ISO 14001 Standard and other environmental management system (EMS)
approaches. The handbook works best in application to manufacturing, but is adaptable in
principle to offshore oil and gas activities.
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Effective pollution prevention requires systematic and effective planning, and incorporation of
pollution prevention with broader organizational planning processes. A general outline of
implementation is provided by the pollution prevention planning checklist in Table 1-3:
Table 1-3
1.
2.
3.
4.
5.
6.
Pollution Prevention Planning Checklist (Environment Canada, 2001)
Commitment and Policy
a.
Obtain senior management commitment
b.
Prepare and communicate a written pollution prevention policy
c.
Assign an accountable manager
d.
Establish a pollution prevention planning team and commit adequate resources
e.
Integrate the pollution prevention planning process with existing management systems, including
any EMS
Baseline Review
a.
Define the system boundaries (scope) of the plan
b.
Assess the existing situation (with good baseline information)
i.
Establish a process and material flow profile of relevant operations and processes
ii.
Quantify inputs and outputs and mass balance
iii.
Calculate total costs and benefits of current approaches
iv.
Identify relevant legal requirements (international, federal, provincial, municipal)
v.
Identify related company policies and targets
vi.
Identify stakeholder concerns and market issues
vii.
Identify business issues including the existing planning and management systems
Planning
a.
Identify pollution prevention opportunities
b.
Establish objectives, targets and performance indicators
c.
Define and involve the affected community and employees
d.
Develop an action plan to meet objectives and targets
i.
Identify specific pollution prevention options, and their environmental, technical and cost
aspects
ii.
Evaluate and rank options based on environmental benefits, technical feasibility, costs
and applicable strategic considerations
iii.
Select preferred options and assign responsibilities, resources and timelines
Implementation
a.
Implement the selected options
b.
Identify employee training needs and provide training
c.
Integrate with existing management systems
d.
Create support mechanisms (e.g., incentives, penalties, internal and external communications,
reporting forms)
Monitoring and Reporting
a.
Monitor implementation of the plan and performance against objectives and targets
b.
Document the results, including costs, savings and other benefits
c.
Take corrective action if necessary
d.
Report to management and to the public
Review, Evaluation and Improvement
a.
Conduct regular reviews of implementation progress and performance results
b.
Identify changing internal and external circumstances
c.
Revise the objectives and targets, resource allocation and action plan as required
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Commitment and Policy
A written policy of preventive environmental management is needed to provide broad support
and demonstrate the commitment of the company. Accountability supported by sufficient
authority and resources should be provided to a senior manager. Pollution prevention may be
fully integrated into an EMS, so that separate documentation may not be required.
Baseline Review
Detailed information is required to identify the most significant pollution prevention
opportunities and information gaps. System boundaries should be defined, as where the boundary
is set can influence the options considered. For instance, value engineering practices can be
applied to identify pollution prevention opportunities; however, this tends to be focussed on
construction only or capital costs only and not on operating costs. Setting pollution prevention
boundaries so that all phases of a project can be considered holistically may justify higher
construction costs, when net pollution prevention benefit (and net project cost savings) can be
demonstrated.
Within the boundaries identified, the review requires the completion of a detailed profile of all
processes, including quantification of all inputs and outputs. This may require detailed life cycle
analysis, which would include emissions, discharges and disposal of materials.
Other internal or external factors may also be considered. These include regulatory requirements,
stakeholder issues and concerns, and internal policies and procedures.
Planning
Planning builds on the baseline review through iterations of objectives and targets from tentative
to specific and detailed options. These should be identified to prevent on-site releases and offsite transfers for disposal and recycling. They should also prevent pollution associated with
pollutants contained in products that are taken off-site.
Pollution prevention should be considered for the full life cycle. In manufacturing the full life
cycle of a product would be considered; in offshore oil and gas the full life cycle of a project can
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be considered. Objectives and types of pollution prevention practices for the full life cycle of
project are listed in Table 1-4.
Table 1-4
Possible Pollution Prevention Objectives and Practices (adapted from Table 2, p. 15,
Environment Canada, 2001)
Project Stage
Design
Raw material
acquisition and
processing
Exploration
and
development
Possible Objectives
Reduce material intensity
Extend product life
Reduce pollutants from product
use
Increase use of low-impact
materials – renewable, low
energy content, recycled and/or
recyclable;
Reduce materials – reduce
weight, reduce storage volume,
reduce transport volume, reduce
number of different materials
Increase clean operations – low
and clean energy use, water
conservation, low waste, few
and clean inputs
Production
Increase clean operations – low
and clean energy use, water
conservation, low waste, few
and clean inputs
Use, reuse and
maintenance
Minimize user impact – low
energy use, clean energy use,
low water use, low material use
and waste generation, low
emissions
Optimize initial life – adaptable
and upgradable, reliable and
durable, easily maintained and
repaired
Optimize end-of-life – ensure
that products are reused,
remanufactured, recycled or
safely disposed
Disposal
Possible Practices
Design and
reformulation
Example Applications
Slim hole design
Drilling fluid selection
Design and
reformulation
Materials and feedstock
substitution
Purchasing techniques
and inventory
management
Drilling fluid additive
selection and substitution
with less toxic chemicals;
optimize re-use of drilling
fluids; inventory
management to minimize
waste materials
Equipment
modifications and
process changes
Operating efficiencies
and training
On-site reuse and
recycling
Equipment
modifications and
process changes
Operating efficiencies
and training
On-site reuse and
recycling
Expandable casings;
Reuse WBM
Product design and
reformulation
Materials and feedstock
substitution
Product design and
reformulation
Materials and feedstock
substitution
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Downhole separation of
produced water; re-injection
of produced water; CO2 reinjection; H2S re-injection;
collection and recycling of
glycol and waste oil;
formation oil/water
separation using polymers
Improve efficiency of
motors
SBM use to avoid shipping
cuttings to shore; use muds
that can be renewed and
reused
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Options may be evaluated based on technical feasibility, environmental effectiveness, cost
effectiveness and business considerations relevant to the particular corporate organization.
Technical feasibility may include considerations of availability and proven performance; risk of
non-performance; maintenance requirements; compatibility with existing space, technical
systems and support systems; health and safety implications; labour skills and training
requirements; effect on operational flexibility; and shutdown requirements for implementation.
Environmental effectiveness should consider the magnitude of both benefits and possible adverse
impacts. A benefit in one medium may have potential adverse effects in another. Reductions in
air emissions may be offset by increases in hazardous waste or effluents.
Financial considerations include the difference between the costs of current processes and the
proposed options. Full cost accounting may demonstrate a reduction in overall costs.
Business considerations may provide priorities for evaluation criteria, which may be factors of
legal considerations, regulatory trends, social and cultural issues, corporate image and
opportunities for partnerships.
Action plans should be developed for each option selected. These plans should include specific
targets to meet, tasks required, responsible parties, affected parties, resource requirements, a
schedule and indicators for monitoring. Training requirements may be included. Both internal
and external parties (such as suppliers) should be engaged in both plan development and
implementation.
Further information on developing pollution prevention plans is available through Environment
Canada’s Pollution Prevention website: http://www.atl.ec.gc.ca/epb/pollprev/loapic.html.
Implementation
For implementation, various employees will have responsibility for components of the plan but
one manager should oversee implementation. All employees should be aware of the plan and
some may require relevant training, such as in new equipment operation or waste reduction
procedures.
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Monitoring and Reporting
Monitoring should include plans for status evaluations, including costs and savings as well as
progress towards objectives and targets. Monitoring methods, staff responsibility and monitoring
frequency should be part of the monitoring plans. Where possible, performance indicators and
milestones should be identified.
An outcome of regular monitoring would be detection of variance from objectives and targets to
allow early correction. Records of the monitoring and any corrective actions should be retained
for review. Progress reports are important to maintain momentum and evaluate progress. Public
reporting may be part of the plan to provide benefits in enhanced image and improved
community and government relations.
Evaluation and Improvement
Pollution prevention plans should be continuously re-evaluated and improved. Regular review of
achievements and the appropriateness of objectives and targets should be made in the context of
internal and external considerations. Changes in technology, finances or other considerations
may make new options feasible. The review may identify the need for reallocation of resources;
plan revisions; or objective and target changes.
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Pollution Prevention Priority Topics
The following priority topics are addressed: air emissions, drilling fluids and cuttings, produced
water, biocides and glycol. In addition a single section identifies various other pollution
prevention opportunities relevant to the industry. Under each topic the background is presented
with a description of emission and waste sources and the related processes, as well as the issues
of concern relevant to pollution prevention. Current practices in Atlantic Canada and elsewhere
are outlined. These practices are then discussed in the context of pollution prevention practices
that are available, may become available or may not be suitable for offshore use in Atlantic
Canada. Practices may be unsuitable under current operating or project risk conditions, may be
applicable for development but not for exploration or may be technically undeveloped, but have
some promise for future application. Again, it is noted that pollution prevention should be
applied holistically, so that pollution prevention plans should encompass and consider all waste
and emission sources and all phases and aspects of a project. Comparing options in drilling fluid
selection may incorporate effects on net energy consumption and consequent air emissions, as
well as potential marine effects and health and safety risks. This interrelationship of outcomes
between waste and emissions sources is addressed in Section 3 with case studies.
2.1
Air Emissions
2.1.1
Background
Air emissions include flaring and venting, fugitive emissions and combustion emissions. Flaring
is the combustion of natural gas and light condensates as waste or byproducts. When the
quantities cannot economically, feasibly or safely be collected for sale the practice has been to
burn them as waste. When produced gases do not contain sufficient hydrocarbons to maintain
combustion, they may be freely vented to the atmosphere. The non-hydrocarbon gases are
predominantly CO2 and others such as H2S. Also during well testing hydrocarbons may be
flared, since the quantities do not make collection, transportation and processing/sale of the
hydrocarbons practical.
Fugitive emissions are those that escape to the atmosphere from standard operations or
maintenance procedures. Sources of fugitive hydrocarbons include losses during coupling
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disconnection, leakage out of equipment and losses of the volatile gas volume in liquid storage
systems. Losses of unburned hydrocarbons that would otherwise be flared may also be
considered venting or fugitive losses.
Combustion air emissions are those derived from the engines and power systems used to operate
drilling and production systems. Subsidiary equipment such as cranes, compressors, pumps and
hydrocyclones are necessarily or may be separate emissions sources from the main power
system. Commonly, engines and motors are diesel fuel driven, but other fuels including natural
gas may also be used.
Sources of air emissions from offshore oil and gas activities in Atlantic Canada are characterized
in another ESRF document, Standardizing the Reporting of Emissions to Ambient Air From
Atlantic Canadian Offshore Petroleum Activities (Dillon and Cordah, 2003).
The OWTG require operators to provide in a DPA an estimate of the annual greenhouse gas
emissions from offshore installations and the plans to control and reduce such emissions (NEB et
al., 2002, s. 2.2).
Operators of drilling or production facilities should provide an annual calculation of greenhouse
gas emissions as well as a determination of the type and significance of volatile organic
compound (VOC) emissions. VOC emission rates are to be related to existing Canadian oil and
gas industry best management practices.
Concerns
Emissions of concern are both atmospheric losses of vented or incomplete combustion products
and emissions from complete combustion. The isolated locations of offshore activities generally
make air emissions primarily a concern at the global level, or at most a regional level. Emissions
from incomplete combustion can however impinge locally on the marine environment, if
hydrocarbons settle to the sea surface. The emissions of greenhouse gases, CO2 and methane are
of global concern. Methane emissions from venting, fugitive losses and incomplete combustion
are contributions to greenhouse gases that have a 21 times greater effect than the equivalent
carbon dioxide resulting from complete combustion (Houghton et al, 1995). Therefore, flaring is
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preferable to venting, when there is no alternative. Combustion efficiency is important to limit
the loss of hydrocarbons the atmosphere.
A significant source of flaring emissions can be flaring of methane and light hydrocarbons that
are produced with oil. In the offshore, where there is no available method for collection and
marketing of natural gas produced with oil the past practice has been to flare the gas.
2.1.2
Current Practice
Atlantic Canada Practices
The Hibernia project has ceased its previous operating practice of flaring natural gas and is now
compressing and reinjecting natural gas both for production enhancement and as storage for
potential production and sales in the future. Technologies for the shipping of liquified natural gas
and compressed natural gas may become economical. From 90 to 95% of produced natural gas is
now re-injected and 3 to 4% is used for power production. The power generation systems are
dual fuel turbines, so that when there is sufficient produced gas the use of diesel fuel is
displaced. Some flaring still occurs when the re-injection compressors are not operating, but
there has been a yearly decline in the flaring (Hibernia web site; D. Burley, pers. comm.).
The EnCana Deep Panuke project has been designed to prevent the discharge of both H2S and
associated CO2 by re-injection to an underground formation. Offshore processing would strip
acidic gases hydrogen sulphide and carbon dioxide from the natural gas to meet sales gas
specifications. Natural gas liquids and water would also be separated. Since the ratio of
condensates to natural gas is low, the condensate would be used as fuel for the power needs of
the production and processing facilities. Seawater scrubbing of these gases was considered in the
initial project design, and rejected in favour of re-injection. Seawater scrubbing would almost
eliminate H2S air emissions, but not CO2, and would transfer sulphur to the ocean. The reinjection formation would be selected to prevent accidental seepage of the gases, so that they
remain effectively sequestered. Some flaring of acid gas would be required during maintenance
or if equipment malfunctions in the injection system, which may be as much as 5% of the time.
The flaring is required for safety to burn off toxic H2S. Flaring will be minimized by optimizing
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shutdown times for injection compressor maintenance when production levels are low (EnCana,
2002).
Current Practice Elsewhere
Flaring represents around 30% of the UK offshore industry's CO2 emissions (5.5 m tonnes CO2).
During 2001, the industry participated in the voluntary Flare Consents Pilot Scheme. Eleven
companies participated in 2001 involving 63 offshore fields, representing some 45% of UK
offshore production. The companies involved agreed to targets averaging 10% below approved
levels. The scheme led to successes in reducing GHG emissions. Actual flare volumes released
in 2001 (across the industry) were 12.5% less than 2000. The scheme continued to run in 2002.
Other projects were initiated by non-participants in the pilot study and these were successful in
reducing flaring by a similar amount.
2.1.3
Pollution Prevention Opportunities
Avoid Production of Air Emissions
There are few opportunities to completely avoid air emissions. One is the avoidance of well
testing of initial exploration wells, which requires flaring. Testing of discovery wells, as opposed
to delineation wells, is not necessary from a reservoir potential standpoint. As a result, some
companies will not test and flare on the first discovery well.
It has been common practice to flare during well testing; however, the amount of flaring has
been reduced recently by limiting the amount of testing, which also reduces the accuracy of
information used to make efficient production decisions. Emission-free sampling and well testing
systems have been designed to both eliminate flaring and improve the quality of data collected.
Halliburton has developed one of these systems (Fosså, 2001), which is a tubing-conveyed,
cased-hole system for liquid reservoirs. The process uses a down-hole apparatus to test formation
pressures and test and sample fluids. Both bulk and small volume samples can be collected. The
system meets all the industry “must have” functions that were anticipated, but does not meet
some of the “desirable but not essential” functions. It is not capable of multi-phase measurement,
limits testing or testing without a rig. In addition to meeting the desired functions, the process
improves well-site safety, eliminates flaring (although not all emissions can be eliminated) and
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reduces overall well test cost, since a smaller test crew is required. Durability and reliability are
provided by the modification of existing components.
Reduce the Amount of Air Emissions
Process and technology improvements and operating improvements can very substantially reduce
air emissions. Both the Hibernia and Deep Panuke projects provide examples that reduce direct
air emissions to the level of about 5% of the uncontrolled emissions. Both the natural gas and
acid gas re-injection have associated air emissions from compression requirements.
Both projects also illustrate changes in power generation or selection of power generation
methods that have the potential to be more efficient. Fuel substitution of diesel with natural gas
or condensate in this manner is a waste to energy use, which would not be considered as
pollution prevention. However, this fuel substitution is good pollution prevention practice since
power must be used for injection and natural gas and condensate are cleaner burning and more
efficient fuels than diesel. In the past natural gas and condensate have been treated as waste
products.
Where conventional diesel engines continue to be used, engine and fuel efficiency can be
improved. Noble Drilling installed commercially available diesel fuel injectors and used engine –
injector-timing retardation on all diesel engine power systems on three rigs. Testing showed fuel
consumption decreased 2% and NOx emissions decreased 30 %, for an expected average savings
of $5,000 a year for each engine. With confirmation from permanent monitoring of sulphur, NOx
and CO2 emissions on four engines of an operating rig, the company may install these emission
improvement devices on all 32 of its drilling rigs in its fleet with the same locomotive-type diesel
engines (Boudreaux, 2002).
Technology is available to reduce operational flaring. Ignition systems that operate in any
weather conditions eliminate the need for a pilot flare (Miles, 2001; see ABB, 2003 for instance).
Continuous flare gas flows can also be recovered. One system provides a rupture disk and
ignition system, so that gases can be diverted to a flare when a specific pressure level is reached,
but continuous lower gas levels can be recovered and used (ABB, 2003).
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Inert blanket gases are commonly used over liquid storage vessels such as those for product
storage on an FPSO. This blanket gas can accumulate significant amounts of VOCs, which are
subsequently emitted to the atmosphere as the vessel fills and the blanket gas is displaced. An
alternative method is the use of a hydrocarbon blanket gas, which eliminates oxygen, but can be
recovered and re-used as the vessel fills (ABB, 2003).
Under the Integrated Pollution Prevention and Control (IPPC) Directive in the EU, it is necessary
to demonstrate that Best Available Techniques are used for certain activities. In the case of
turbines used for power generation or compression, the benchmark for new installations is the
use of low NOx turbines, also referred to as Dry Low Emissions (DLE) turbines. Operators are
expected to use this technology unless there are very good reasons to do otherwise. While this
technology represents BAT for NOx emissions, the technology has the following trade-offs:
•
Due to the increased number of fuel injection points on a DLE Machine, there may be a
higher potential for fugitive releases;
•
DLE machines are generally less thermally efficient than the non DLE Machine, which
increases carbon dioxide emissions; and
•
More complex equipment and control systems increase the likelihood of breakdown and
hence greater venting emissions.
Clean burner technology can be applied to control combustion of flared gas or hydrocarbon
fluids. Proprietary ‘super-green burners’ maximize the efficiency of the burning process by
ensuring the appropriate airflow to the burner. Use of the technology minimizes hydrocarbon
dropout to sea.
A case study is presented for the sequestration of CO2 in Section 3.8.
2.2
Drilling Fluids and Drill Cuttings
2.2.1
Background
Drill cuttings are the mineral particles produced by the drill bit from the native bedrock. Cuttings
are removed from the borehole by dense drilling fluid formulations or muds. Drilling fluids are
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also used to lubricate the drill stem in the borehole, stabilize the borehole, and may be used to
hydraulically turn the drill bit. For the top hole sections of a well, where there is no casing
installed, sweeps of WBM are used to clean cuttings away from the bit and the muds and cuttings
are discharged to the seabed. Once casing is installed in a well, drilling muds and cuttings are
returned to the drilling unit through the riser. Cuttings are removed from the muds and the muds
are re-used if they are suitable.
There are several methods of managing the waste cuttings and muds. The cuttings disposal
methods used can vary with the type of mud used, the location of the well and regulatory
requirements. Cuttings from WBM are generally discharged to sea from the drilling unit.
Cuttings separated from muds with synthetic oil (SBM) as a lubricant may also be discharged to
sea in some jurisdictions. The general alternatives to discharge to sea are shipping to shore or reinjection into bedrock through an existing or purpose drilled well. Re-injection requires access to
a bedrock formation that will accept and retain injected cuttings. The former common practice of
using diesel fuel in oil based muds (OBM) has been generally discontinued and is not discussed
further. However, EMOBM1 uses similar oils, which have been purified to remove most of the
polycyclic aromatic compounds (PAH) and to reduce toxicity, are used when cuttings are not
discharged to sea. Once shipped to shore oily cuttings may be treated, re-used or managed on
land.
Except for the uncased well sections, muds are usually re-used after cuttings have been separated
from them. WBM is commonly discharged to sea when it can no longer be used, which is often
after a single use. SBM and LTMO that is no longer suitable for use may be re-injected or
shipped to shore. Some muds may be reconditioned at shore-based facilities for reuse on another
well.
Other Mud Components and Additives
There are a variety of additives used in drilling fluids to modify their properties and enhance
their performance. In addition to the major components of bentonite clay and barite, categories of
1
EMOBM is defined in s. 2.4 of the OWTG as containing highly-purified petroleum distillate that has a PAH
content less than 10 mg/kg.
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additives that may be used include scale inhibitors, viscosifiers, corrosion inhibitors, wetting
agents and dispersants.
Beyond the initial selection decision between WBM or SMB/EMOBM use, the application of
pollution prevention to the formulation of drilling fluids is supported by the Offshore Chemical
Selection Guidelines (OCSG) (NEB et al., 1999). The OCSG provide criteria for the selection of
chemicals for use in offshore drilling and production that are to be discharged to the
environment. Considerations include CEPA listed substances, substances known to cause
tainting in fish tissues, and hazard rating. Tainting and an early acceptability criteria are based on
substance evaluations by the Oslo and Paris Commissions (OSPAR) sources. Substances passing
these criteria are rated for hazard by the UK Offshore Chemical Notification Scheme (OCNS),
which classifies chemicals using test protocols approved by the OSPAR under the requirements
of the Harmonised Offshore Chemical Notification Format (HOCNF). The OCNS assigns hazard
ratings from the most hazardous category of A to the least hazardous category of E. Toxicity
testing, discharge quantities and chemical specific hazard analysis may be required to determine
the suitability of a substance rated in group A or B. With each step of the review, substitution of
substances by less hazardous alternatives is reinforced.
Chemical selection for use on the UK offshore now goes beyond the criteria specified in the
OCSG. Since May 2002, in the UK chemical selection is to be administered under the Offshore
Chemical Regulations 2002 (OCR 2002). Offshore chemicals are to be ranked according to their
calculated Hazard Quotients (HQ) - ratio of Predicted Environmental Concentration (PEC) to
Predicted No Effect Concentration (PNEC). The CHARM "hazard assessment" module is used
as the primary tool for ranking. This is carried out by a multidisciplinary CEFAS team (the
Centre for Environment, Fisheries and Aquaculture Science [CEFAS] is an Executive Agency of
the UK Department for Environment, Food and Rural Affairs). The HOCNF can be filled in to
suit the CHARM model.
Inorganic chemicals and some organic chemicals have functions for which the CHARM model
has no algorithms. These will continue to be ranked using the existing OCNS hazard groups. A
complete description of the OCNS assessment process can be found in the CEFAS guidelines to
the non-CHARMable chemical assessment process (CEFAS).
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The Offshore Waste Treatment Guidelines (NEB et al., 2002) allow drillers to apply for approval
to discharge SBM cuttings with 6.9% retained oil on cuttings as wet weight, although the use of
WBM is preferred. To reach these levels additional treatment of cuttings beyond the
conventional cutting from mud separation equipment (shale shakers) is required such as
hydrocyclone cuttings dryers. WBM cuttings and whole WBM may be discharged to sea, but
whole OBM cannot be discharged to sea under any circumstances, including SBM and EMOBM.
Unused SBM and EMOBM may be recovered and recycled, reinjected or shipped to shore for
disposal.
Concerns
Concerns about the discharge of drilling fluids and cuttings relate to the fate of particulate
material in the marine environment as well as the potential toxicity of fluid components.
Deposits on the seafloor may smother benthic organisms and high concentrations of suspended
solids can affect marine organisms. Tainting of commercial species, most notably scallops, is
also a potential effect from oil on cuttings. SBM and EMOBM oils on cuttings deposits will
decompose, but this may cause oxygen depression and resulting smothering of benthic
organisms.
2.2.2
Current Practice
Off Nova Scotia and Newfoundland, operators apply each of the practices outlined above. Where
discharge to sea is allowed or land disposal is readily available, costs are likely to discourage reinjection.
Atlantic Canada practice is consistent with the US. The EPA published regulations to establish
technology-based effluent guidelines and standards for discharge of SBM cuttings beyond 3
miles offshore. These regulations apply to the Gulf of Mexico and Alaska with the exception of
coastal Cook Inlet. The EPA rule recognizes the use of SBM use as a pollution prevention
method when cuttings are discharged to sea when base fluids and cuttings discharge criteria are
met. Retained oil on cuttings limits are set at 6.9% wet weight. Base fluids are regulated for
toxicity, biodegradation, PAH and metals content.
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In the North Sea, the UK and Norway have set a retained oil on cuttings discharge maximum of
1 %. Since technology is not available to reach this level this is an effective ban on the discharge
of cuttings with retained oil. Oily cuttings are re-injected or shipped to shore.
Muds and cuttings that are shipped to shore may be disposed of in a landfill or treated and
disposed of or used in various ways. Drilling muds are also reprocessed onshore for re-use in
drilling.
For more information on the current management and handling of drilling wastes, the reader is
referred to: Offshore Drilling Waste Management Review, February 2001 by the Canadian
Association of Petroleum Producers and http://www.cnsopb.ns.ca/Generalinfo/exploringoilgas.html.
2.2.3
Pollution Prevention Opportunities
Avoidance of Muds and Cuttings as Wastes
The use of muds and production of cuttings is essential to exploration and development drilling.
In some locations the first top hole section can be developed by jetting instead of drilling, if
suitable unconsolidated overburden or soft rock is present. This avoids the use of any drilling
fluids for that section, and simply displaces the native material onto the seabed.
Re-injection is effectively an avoidance process, because injected muds or cuttings are
sequestered within bedrock and are neither discharged to the marine environment nor shipped to
land for disposal. Re-injection requires an available well and suitable bedrock formation, which
are not usually available during exploration or early in development. An exploration project that
used re-injection is described in the case examples (Cook Inlet, Section 3.3).
Reduce the Amounts of Materials Used and Waste Disposal
Methods that reduce the amount of muds used and the amount of cuttings produced fit this
category. The use of SBM or EMOBM reduces the diameter of well drilled and consequently the
volume of muds used and cuttings produced. Oil based muds provide better lubrication, better
borehole stability, less loss of fluids to bedrock and reduced reaction with shale. In using SBM or
EMOBM, not only can be borehole diameter be reduced, but less mud is wasted and fewer
cuttings produced relative to the well diameter than with the use of WBM. The use of SBM or
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EMOBM also allows faster drill penetration rates, which serves to reduce drilling time and the
associated energy use and associated emissions. The concept of slim hole technology applies the
design of drilling programs with the minimum diameter necessary to complete the well. A risk of
this approach is ‘running out of diameter’ if more decreases in casing diameter are required than
expected.
The practice of drilling multiple wells from a single location, using directional control of drilling,
offers similar financial economy and associated reductions in the environmental footprint of
drilling.
If well diameter can be reduced sufficiently, it is possible that the riser diameter may also be
reduced. This would allow the use of smaller drilling units, again reducing the energy
requirements and air emissions as well as reducing costs.
Recently, expandable casings have been experimentally used to drill wells. Conventional well
diameters and casing diameters decrease as a well is drilled deeper. Casings have to be small
enough to be ‘nested’ so that new casing can be run through the inside of previously cased well
sections. Expandable casing has been used to produce onshore wells with a constant diameter
from top to bottom. Experimental application of this technique is proceeding in offshore
applications (see Case Studies, Section 3.2).
Control Disposal
Many options are available for the onshore re-use, treatment or disposal of cuttings. Although reuse and recycling off site is not generally considered as pollution prevention, a benign use of the
waste material in place of some other raw material use, i.e. to replace quarried granular material
in a product or process, is good environmental management.
A recent project by Mott MacDonald and BMT Cordah, funded by Shell and BP, looked at
existing and innovative methods for the recycling of cuttings. Although the details of this report
are confidential, the Executive Summary has been released into the public domain and provides
an overview of recycling methods in the UK and general practices in cuttings re-use and disposal
worldwide.
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In this project, a total of 95 potential recycling opportunities were originally identified.
Screening against environmental and commercial evaluation criteria indicated that the following
ten specific recycling options were considered appropriate for further consideration:
•
Use in estuarine restoration
•
Use in cement manufacture
•
Use in land reclamation and landscaping
•
Use in road pavements, bitumen and asphalt
•
Use as fuel and pulverised fuel ash
•
Use as pipeline bedding and sub-base
•
Use in roof tiles
•
Use in pipeline coating
•
Use in concrete block and ready-mix
•
Use in path construction
The following table summarises a number of worldwide activities relating to the recycling and
disposal of drill cuttings. This indicates the types of recycling and disposal routes that have been
tried. Not all have been successful, and in many cases further data has been difficult to obtain.
Note that no further details of these activities are available.
Table 2-1
Worldwide Activities Relating to Drill Cuttings Disposal
Activity
Incineration (ash to landfill)
Bioremediation and Land Farming
Landfill
Landfarming
Cement
Cement
Desorption to Landfill and Quarry Roads
Supercritical Extraction to Land Farming
Roof Tiles, Statoil
Chloride Free Bioremediation to Land Farming
Concrete
Landfill Liners
Land Farming
Replacement of Chlorides in muds with Formates (not a
recycling solution, but a relevant issue)
Incineration and Land Farming
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Location
Norway
Norway
Norway
France
Austria
Azerbaijan
Canada
USA
Norway
Canada
Alaska, USA
USA
USA
Alberta, USA
Venezuela
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Activity
Land Farming
Spreading on Roads
Rotary Kiln to Bricks
Incineration
Landfill (very little OBM)
Chloride Free BioRemediation to Landfarming
Chloride Replacement with Nitrates, Landfarming
Landfill
Land Farming
Land Farming
Land Farming
Land Farming
Location
Brazil
Argentina
Colombia
Nigeria
Australia
New Zealand
Canada
Adriatic Sea
Sharjah, UAE
Egypt
Indonesia
Colombia
Other Issues/Limitations
Health and safety may also be a consideration in comparing drill cuttings disposal options.
Onboard treatment of cuttings for discharge to sea, whether of WBM or SBM cuttings, may
present less health and safety risks. The multiple lifts and associated handling required for the
skips used to store and ship waste cuttings to shore would have some safety risks, both for
movements on the rig deck and on and off-loading to supply vessels and ultimately trucks.
Although custody may be legally transferred to the receiving disposal facility, some operators
may consider on-land disposal as a long-term liability. Discharge to sea might also be considered
a long-term liability. In comparing additional cuttings treatment using additional treatment
equipment with shipping cuttings to shore, available deck space may be an important decision.
Bedrock drilled in the Gulf of Mexico produces cuttings that are generally coarser than in the
offshore in Atlantic Canada. Lower oil on cuttings retention levels are achievable in the Gulf of
Mexico with current technology. Nova Scotia, Newfoundland and Labrador and North Sea
bedrock produces finer cuttings so that adhered oil is higher and more difficult to remove to meet
discharge criteria.
Re-injection might be economically feasible if development and operating costs could be shared
between several operators. However, corporate considerations of liability issues may make this
less attractive. For such a solution the added cost and energy requirements of getting wastes to a
central re-injection well should be considered. Cuttings may need to be slurrified for shipping
and injection, which adds to costs and increases emissions.
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2.2.4
March 2004
Future Pollution Prevention Opportunities
With ongoing technological changes and the continued approval of the practice of discharging
treated SBM cuttings in most US offshore drilling areas and in Atlantic Canada, continuous
improvements are possible or likely in several respects. Overall cuttings volumes per well may
be reduced as technology improves for slim hole wells and subsequently constant diameter wells.
The percentage of synthetic oil retained on cuttings may decline as best available technology
improves for cuttings treatment. There has been a stated benefit in response to the regulatory
acceptance of the discharge of SBM cuttings to sea. More research and development effort has
been dedicated to synthetic oils now that their use has been enabled. This is likely to eliminate
toxicity and maximize decomposition rates, since rapid decomposition is the selected strategy for
environmental protection in the EPA decision. The continued improvements in SBM will have
the additional benefit of reducing the environmental effects if spills of SBM or drilling fluid
components occur.
Conversely, while there are some benefits to the use of WBM in cased well sections, shale
control remains difficult with WBM. Where SBM cuttings cannot be discharged but WBM
cuttings and muds may be discharged, there is some market benefit in improving the
performance of WBM. Generally difficult drilling, such as directionally drilled and extended
reach wells, require the use of SBM or EMOBM muds for their higher lubricity and also shale
inhibition. A large diameter extended reach well was planned and drilled with WBM in the North
Sea Central Graben. Such wells have historically been drilled with mineral oil or ester based
drilling fluids. WBM was used because of the high cost of the required shipping of SBM cuttings
to shore and the risk of shutdown in bad weather if cuttings boxes could not be off-loaded to
supply vessels. The well was planned to determine shale inhibition requirements and required
mud weights, which resulted in a well trajectory design change to a lower angle through problem
shale formations. The size of cuttings was also carefully controlled. The well was successfully
drilled with no significant hole instability problems (Stawaisz et al., 2003). This illustrates a
successful pollution prevention practice through design and substitution.
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2.3
Produced Water
2.3.1
Background
March 2004
Produced water is an unavoidable waste of the oil and gas production processes. Produced water
occurs naturally in subsurface formations and must be separated from the extracted oil or gas.
For some production, seawater may be injected into the formation to maintain pressure and
replace the petroleum products removed and this injected water may be recovered with
petroleum products as produced water. Produced water quantities generally grow as a reservoir is
depleted. In the offshore, produced water is usually discharged to the sea.
Guidelines for produced water discharge limit the concentration of oil in water discharged in
Atlantic Canada. Concentrations must not exceed 30 mg/L (as a 30-day weighted average) and
the 24-hour arithmetic average must not exceed 60 mg/L. These limits apply to facilities
permitted after August 2002. Installations producing prior to that date can discharge up to 40
mg/L (as a 30-day weighted average) until December 31, 2007. Produced water discharges must
be analysed for a suite of 18 metals plus N and P twice a year. The sea urchin fertilization
aquatic toxicity test and at least two other bioassay tests must be completed annually for water
that is also given the chemical analysis. (C-NSOPB et al., 2002)
These targets are consistent with the new OSPAR target of 30 mg/L, which is expected to
contribute to achieving a 15% reduction in tonnes of oil in water discharges between 2000 and
2006. This target is a challenge for older platforms and depleted reservoirs with large proportions
of produced water.
Concerns
While much of the produced water is similar to seawater, if more concentrated, produced water
also includes hydrocarbons, heavy metals and naturally occurring radioactive materials. These
contaminants of concern occur in varying concentrations that differ strongly between oil and gas
sources, differ generally between basin areas and can differ significantly within the same
reservoir. Management of produced water may require the use of additives such as anti-scaling
or anti-corrosion chemicals, which are discharged also.
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2.3.2
March 2004
Current Practices
Current practice in Atlantic Canada and elsewhere is to discharge produced water to the sea after
treatment to reduce hydrocarbon levels. In most settings this results in the rapid dilution of the
produced water over short distances to concentration levels of most constituents to background
levels or to non-detectable. While it can be shown that toxic conditions for some organisms can
be reached in the discharge plume, these conditions are short term. Studies of the potential for
bioaccumulation and biomagnification have generally shown these processes to occur. Some
bioaccumulation has been measured in organisms attached to production facilities; however, the
levels reached were neither harmful to the organisms or a risk to consumers or predators. Studies
of the fate of produced water constituents have found elevated levels of some components in
sediments in the vicinity of the discharge, but these could also be attributable to other sources,
such as muds and cuttings. For these reasons it is considered appropriate under most regulatory
regimes and in most marine settings to discharge produced water following hydrocarbon
removal.
The Sable project uses treatment of produced water to meet guidelines for discharge to the sea.
EnCana’s Deep Panuke project will use a similar method. However, the EnCana project proposes
to treat produced water using hydrocyclones to remove oil to meet the guidelines (C-NSOPB et
al., 2002) with a voluntary project target of 25 mg/L. The hydrocyclone is expected to reduce
produced water oil concentrations to the 30 to 50 mg/L range. Further oil removal will be
achieved using an organophyllic clay treatment process. The clay will itself be a waste product
requiring onshore disposal. Produced water will also be treated in a stripper to remove H2S down
to a 1 to 2 ppm concentration. The discharge stream of treated produced water (after it is treated
to meet guidelines) will be mixed with cooling water to at least an 85 to 1 dilution prior to
discharge. (EnCana, 2002 and G. Hurley, pers. comm.)
2.3.3
Pollution Prevention Opportunities
There are three general approaches to P2 that can be considered for the management of produced
water. In the order of preference for pollution prevention these are:
Avoid the Production of Produced Water as a Waste
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Avoidance of the discharge of produced water into the marine environment is possible through
re-injection of the water into underground formations. The receiving formation may be the
hydrocarbon source reservoir, a depleted reservoir or an aquifer.
Re-injection is not currently practiced or considered practical for production facilities in Atlantic
Canada.
Although petroleum products and produced water cannot strictly be separated within the
reservoir, it is possible to separate petroleum products from water close to the point of extraction
rather than at the sea surface. Technologies exist for downhole separation of oil and water and
gas and water. Separation is also possible at the seafloor. The produced water must then be reinjected.
Constraints to re-injection are: availability of an injection well and suitable formation.
Environmental costs to consider are: energy required and associated air emissions. Potential
economic benefits: maintenance of reservoir pressures.
In addition to reduced or eliminated discharges, the advantages of downhole or seafloor
separation are reduced pumping and related emissions and energy costs. Re-injection may
require the development of dedicated wells, with associated mud and cuttings management, air
emissions and energy consumption. [e.g. for practical downhole re-injection, the Sable project
would need a dedicated well at each production well; the operator of Deep Panuke might be able
to re-inject to the depleted CoPan reservoir.] Re-injection also may require the use of treatment
or additives to the water to prevent the development of sour conditions in the formation, which
would have considerable cost and environmental consequences if treatment failed.
Reduce the Amount of Produced Water or Associated Discharges
There is no known method of reducing the total volume of produced water except by downhole
separation. It would be possible to change the timing of produced water generation by
controlling production rates. It should be noted that most down-hole produced water separation
technologies are a reduction rather than an avoidance method as they do not eliminate produced
water disposal requirements. Some proportion of water is still produced that must be treated on
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the production platform, which retains all the requirements to operate a treatment system
onboard and discharge of waste water to the sea.
Control the Waste Management Processes Related to Produced Water
Since treatment is not a P2 strategy, and the total amount of produced water from the reservoir is
effectively a fixed amount, P2 control strategies for waste management of produced water are
those that reduce the discharge of toxic substances or use of energy. Reduced or less toxic
additives are addressed under biocides in Section 2.4. Aspects of energy use reduction are
addressed in air emissions, Section 2.1, may be relevant to produced water management.
Selection of chemical additives for treatment or management of produced water must follow the
Guidelines Respecting the Selection of Chemicals Intended to be Used in Conjunction with
Offshore Drilling and Production Activities in Frontier Lands (C-NSOPB et al., 1999).
Downhole and Subsea Water Separation and Injection
Downhole oil/water separation (DOWS) and gas/water separation (DGWS) is recent technology
that has not been applied in Atlantic Canada. Subsea separation systems are also in development.
DOWS has the potential to increase well profitability through the combination of increased
production rates, lower produced water management costs, and extension of the production life
or recoverable reserves. Some DGWS processes are designed to eliminate surface generation and
handling of produced water (PTAC, 2000).
The Troll C subsea water separation and injection system has been successfully piloted and
operated in the operation of Norwegian productions wells in 350 m of water (Horn and Soelvik,
2002). Details of this system and its application are provided as a case study in Section 3.7.
Most experience with downhole produced water management has been in onshore production
wells. High variability in success and early failure of many systems make the technology still
high risk (PTTC, 2000). Currently high risk technology is unlikely to be adopted in the frontier
production of Atlantic Canada. With the high cost of operating production facilities offshore, the
use of risky technology would require unacceptable shutdowns or 100 % backup with
conventional produced water separation systems in case of the failure of a separation system.
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When reliable systems are proven, the technology is likely to be adopted for the financial as
wells as environmental benefits that are offered.
Hydrocyclone Process
An emerging technology for treating produced water from oil fields is being tested at Statoil’s
Statfjord B platform. Statoil will be conducting a long term test of the CTour technology which
uses natural gas condensate to remove hydrocarbons from produced water. In this process, the
produced water is injected with condensate which acts as a solvent which separates from the
water together with other hydrocarbons when the mixture is hydrocycloned. The separated
hydrocarbons and condensate are cycled back into the production stream.
Initial findings of research into the CTour process showed improved removal of hydrocarbons
when the process was piloted. Another benefit noted was a reduction in flare gas emissions from
the de-gasser. As well, it involves no irreversible changes in the process and resulted in only
marginal increases in capital and operating costs. One limitation noted by the researchers was
that in order to effectively remove BTX (benzene, toluene, xylene) from produced water, the
condensate needed to be virtually free of BTX, in particular, benzene.
2.4
Biocides
2.4.1
Background
Biocides are used in two ways. Seawater systems are used on drilling and production facilities
for cooling and firefighting water, and biocides are used in these systems to prevent the growth
of marine organisms. Biocides must also be used in injection water used for production
enhancement, as live sulphate reducing bacteria injected into hydrocarbon formations during reinjection could sour the reservoir by converting sulphur oxides to H2S.
Without biocides, seawater piping and heat exchangers would become clogged with marine
growth. Mussels are a particular problem. With a high flow in a flow through cooling system
ideal conditions are created for rapid mussel growth, since they have ample food supply that can
be filtered from the passing flow. Mussels can completely block these piped systems.
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No levels for the use or discharge concentrations of residual chlorine are prescribed in the
OWTG, although the Chief Conservation Officer may restrict the levels discharged. Approval is
required for the use for a biocide other than chlorine in cooling water.
Concerns
The most common biocide used in seawater systems is chlorine. The main sources of chlorinated
wastewater effluents (CWWE) in Canada are municipal wastewater treatment plant discharges
and cooling water discharges from thermal and nuclear power generating stations. CWWE are
considered “toxic” under paragraph 11(a) of CEPA (1999) based on the harmful effects of
chlorinated effluent discharges from municipal wastewater treatment plants on freshwater biota.
However, review of effects on the environment of CWWA has not been determined in terms of
the toxicity on marine biota (CEPA, 2003a).
2.4.2
Current Practice
Biocide Use in Atlantic Canada
Chlorine is usually introduced to the seawater intake by a sodium hypochlorite generator. The
rate of chlorine injection can be adjusted so that free chlorine remains below a design level at the
discharge point and biological growth is prevented or inhibited throughout the piped system. For
instance, for the Deep Panuke project the design chlorine concentration at the intake of 2 ppm
would be expected to keep the discharge of free chlorine levels below 0.25 ppm. Normally the
intake concentration would be 1 ppm, but this would be increased during periods of high larval
mussel concentrations determined by a monitoring program (EnCana, 2002).
2.4.3
Pollution Prevention Opportunities
Pollution Prevention by Substitution
Where practical alternative biocides may be used to substitute less toxic substances for those
currently used. The chemical selection guidelines (NEB et al., 1999) provides the procedure for
the evaluation, hazard analysis and acceptance of new substances.
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Minimization
Monitoring and process control can limit the residual chlorine levels in the discharge water and
adjust the input quantities of chlorine. A high residual chlorine level indicates that more is being
generated than necessary and inhibition can be maintained with reduced chlorine input levels.
Electrolytic Systems
Electrolytic systems using copper and aluminum or iron anodes are employed in several marine
applications including ships, e.g., the Canadian Navy, drill rigs, e.g., the Glomar Grand Banks
and platforms. The anodes are fed by an impressed electrical current which results in the
production of copper ions that provide biological control through the creation of an environment
in which common fouling biota such as mussels cannot settle or multiply.
2.5
MEG
2.5.1
Background
Mono-ethylene glycol (MEG) is used for pipeline gas dehydration, and as corrosion and hydrate
inhibition in combination with pH stabilization. Other glycols, such as triethylene glycol and
propylene glycol can also be used. The largest amounts of glycol are used for gas dehydration.
Glycols are also used in smaller amounts as an additive to WBM to add viscosity, for surface
deicing and in BOPs.
Discharge of MEG requires the approval of the Chief Conservation Officer. Discharges of
produced water with MEG present must be monitored and reported. (NEB et. al., 2002, s. 2.15)
Concerns
MEG and other ethylene glycols (di- and tri-) are CEPA listed on the Priority Substances List 2.
However, the assessment of ethylene glycols did not indicate that adverse effects are likely from
the single largest source of these substances – aircraft de-icing. These sources were considered
unlikely to result in adverse effects if discharges to freshwater aquatic environments are below
concentrations of 100 mg total glycol/L, which is the current CEPA guideline level. Ethylene
glycol decomposes rapidly in the aquatic environment, so in some receiving environments
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discharges may produce oxygen depletion. Potential marine effects are not identified in the
assessment report. Further study is in progress and ethylene glycol has not been determined to be
“toxic” or not “toxic” (CEPA, 2003b).
2.5.2
Current Practice
In the Atlantic Canada offshore, the Sable project uses MEG with other corrosion inhibitors in
the transmission of gas and condensate from satellite platforms to the Thebaud central
production platform. The MEG is recovered and conditioned for re-use. Triethylene glycol
(TEG) is used to dehydrate gas before transmission to shore. The TEG is also regenerated and
reused.
In the design of the Sable project, the use of propylene glycol was considered. This alternative
was rejected since the toxicity in the marine environment of propylene glycol and MEG are
similar and very low, and the propylene glycol is significantly more expensive.
In most processes, the glycol becomes contaminated, becomes waste and needs to be replaced or
cost effectively reclaimed. Contaminated MEG is discharged to sea from the Thebaud platform.
There are systems available to reclaim MEG, such as the Kvaerner system used on the Åsgard B
platform.
2.5.3
Pollution Prevention Opportunities
Within Kvaerner Process Systems, a proprietary MEG reclaimer process technology has been
developed since 1996. The unit provides the largest continuous reclamation capacity ever built
and has been in operation since 2000. Kvaerner notes that in addition to hydrate prevention MEG
provides pipeline corrosion protection. Pipelines can be constructed in carbon steel rather than
duplex, resulting in major cost saving (Kvaerner).
There may be a tradeoff required in designing a system using MEG between the capital costs of
construction and the operational cost of replacing contaminated MEG. Comprehensive pollution
prevention planning as part of project design would consider both construction and operating
costs.
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There are also alternative products that can be used for hydrate control. An example is provided
in Section 3.8.
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Other Opportunities, Examples and Case
Studies
This section presents seven topics that provide other opportunities for pollution prevention or
examples not within the topics presented in the previous section. For instance, slender well
design (Section 3.1) is an available technology that may be applied in Atlantic Canada. Its
relevance to pollution prevention is in the potential both to reduce the volume of drill muds and
cuttings and to reduce the air emissions and associated energy costs for a well. However, a risk
of the technology is “running out of diameter” before the design total well depth is reached.
Expandable tubular casings (Section 3.2) provide a technology in development that may reduce
the risks or ultimately supplant slender well design.
3.1
Slender Well
Slender well technology has evolved from use in shallow onshore reservoirs to be used in
deepwater applications. Drilling a smaller diameter well reduces the amount of mud used and the
amount of cement and may reduce the drilling time by 30 %. This not only reduces costs but also
reduces air emissions (Mitchell et al., 2002)
Capability was added to the Bredford Dolphin semi-submersible drill rig to allow slender-well
drilling in water as deep as 1500 m. Slender-well technology uses a 16" riser instead of the
traditional 20 - 22" riser. The resulting reduction in deck load and riser load allows the use of
smaller rigs in deepwater. The use of drilling mud is reduced considerably and the energy
consumption per well is reduced (Dolphin News, October 2001). However, the harsh conditions
offshore in Atlantic Canada may not be suitable for such smaller rigs. Slender well design still
has the potential for faster well completion, requires less mud and cement and produces less
cuttings, even if used on larger drilling units.
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March 2004
Expandable Casings
New technology is being developed and tested that uses expandable casing to eliminate the
telescoping effect that is used in current well design. Onshore application of the new technology
has demonstrated the potential for its use in the offshore. The technology can also potentially be
used to overcome problems commonly encountered in deep wells before total depth is reached.
This will allow slender well designs to be used with less risk of “running out” of well diameter
before reaching the planned total depth. Other potential benefits are a reduction in the size of rig
needed, which reduces emissions, reduction in drilling mud used and a reduction of up to 50% in
drill cuttings. Rig cost savings as well as savings in consumable costs are expected. A
MonoDiameter well is planned in the Gulf of Mexico in 2003. (Sumrow, 2002a)
Expandable casing technology has the potential for applications to all wells and all phases of
well use. The technology is being tested to repair corroded casing and retain most of the well
diameter, and consequently maintain high production rates (Sumrow, 2002b). With the capability
of casing a well with the same diameter from surface to total depth, if wells can reach reservoirs
with the wellbore at high diameters, fewer wells will be required to recover the full potential
from reservoirs.
3.3
Mud and Cuttings Disposal
In Cook Inlet Alaska OBM waste drilling fluids and cuttings have been re-injected during an
exploration program. Although in Cook Inlet WBM can be discharged to sea, oil based muds or
oily cuttings cannot be discharged. Bedrock conditions make oil based drilling fluids much more
effective than WBM. There are no disposal sites for muds and cuttings on land near the
exploration area and a dedicated onshore facility was considered too expensive. For an initial set
of 2 exploration wells OBM cuttings and muds were annulus injected, with the requirement to
store some wastes temporarily on land when annulus integrity became a concern. A dedicated
disposal well was drilled for injection of muds and slurrified cuttings from two additional
exploration wells. Future wells in the exploration and development by the operator Forest Oil on
the Redoubt Shoal structure will introduce zero discharge of drilling fluids and solids using the
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dedicated injection well and developed fit-for-purpose cuttings re-injection system. (White et al.,
2002)
3.4
Discharge of SBM Cuttings with Retained Oil to
Sea as a Pollution Prevention Measure
The US EPA has approved the discharge to sea of SBM cuttings, with limitations, and considers
the use of SBM as a pollution prevention technique. Limitations include base drilling fluids
criteria and cuttings discharge criteria, which are similar to those of the Offshore Waste
Treatment Guidelines (NEB et al., 2002). The decision was based on anticipated discharges
related to the use of WBM and OBM and in consideration of non-marine environmental
considerations including air emissions, energy use, land disposal, worker safety and spills.
SBM has been in use in the Gulf of Mexico since 1992. However, regulations were not
developed to recognize the much lower toxicity of synthetic oils than diesel or crude oil. The
discharge of SBM cuttings were allowed in the interim while new regulations were developed.
Regulations published in January 2001 are likely to encourage the development of new drilling
fluids based on synthetic oils (Sumrow, 2002c).
The EPA rule related to the use of SBM limits discharges only to SBM cuttings and only where
best management practices are applied. The pollution prevention approach of product
substitution provides stock limitations on base fluids for sediment toxicity, biodegradation rates,
PAH content and metals content. Limits are set for mercury and cadmium content in stock barite.
Discharge limitations also are provided that prohibit the discharge of diesel oil and formation oil,
and set limits for sediment toxicity and aqueous toxicity. The quantity of SBM oil retained on
cuttings is also limited.
In completing the rule, the approach of seeking maximum biodegradation rates was selected.
Some consideration was given to the merits and potential environmental effects of selecting
synthetic oils with slower biodegradation. However, the result of the more rapid re-colonization
of affected benthic areas with rapid biodegradation was considered the preferred approach
(USEPA, 2000a).
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Well averaged discharge of retained synthetic oil on cuttings of 6.9% wet weight is allowed for
base fluids with the environmental performance of C16-C18 internal olefins. The higher
discharge rate of 9.4 % is allowed where the base fluid has the environmental performance of
vegetable esters or low viscosity esters. Environmental performance refers to sediment toxicity
and biodegradation (USEPA, 2000b).
To drill a deepwater well in 2001, offshore Nova Scotia, an offshore operator received approval
to discharge properly treated SBM cuttings to sea, consistent with existing regulations. The
discharge of the cuttings with adhered oil at less than 6.9 % wet weight was consistent with the
OWTG. An on-board hydrocyclone cuttings dryer was added to treat cuttings after they were
separated from the drilling mud. The wellsite was in over 1500 meters of water and was 350 km
from Halifax Harbour, the closest location where cuttings could be shipped for disposal. Without
discharge of cuttings to sea consistent with the OWTG, the operator would have been required to
lease an additional dedicated supply vessel for the shipping of cuttings to shore and supply of
empty cuttings boxes to the drilling rig. Cuttings where the retained oil was in excess of 6.9%
wet weight, were shipped to shore and disposed of in accordance with accepted industry practice.
The cost of operation, energy required and associated emissions to operate the cuttings dryer
were considered significantly less than those associated with operating the additional vessel as
well as the related trucking and cuttings disposal costs and energy use, if those cuttings had been
shipped to shore. Since the well was a wildcat well in deepwater, re-injection of slurrified
cuttings was not practical. Higher potential health and safety risks were also considered, due to
the handling and shipping of cuttings boxes to and from shore; however, these risks were not
quantified. For the location of the well and the chosen drilling method, the combination of
discharge of SBM cuttings per existing regulations and onshore cuttings disposal, was
considered good pollution prevention. (industry, pers. comm.).
3.5
Hydrate Control
Hydrates are water/hydrocarbon solutions that form crystals at temperatures higher than the
freezing point of pure water. They can form in flowlines and either reduce the flow of
hydrocarbons or block flow completely. Hydrates can be removed by pigging, but usually
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hydrate inhibitors are injected to prevent their formation. Methanol or glycol are commonly used
to inhibit hydrate formation, however, as much as 1 for 1 volumes of these conventional
inhibitors to water are needed. Insulation of flowlines or active heating can be used on oil
flowlines. However, for start-up and shut-in or re-start flow assurance chemicals are needed
when these methods are used.
Two types of low dosage hydrate inhibitors (LDHI) have been developed - anti-agglomerates
and kinetic inhibitors. Anti-agglomerates function by bonding to microscopic ice crystals and
preventing the formation of large crystals. Kinetic inhibitors delay hydrate formation but do not
prevent it, so are not effective in extended pipelines in cold conditions. LDHI can be effective at
a ratio of 1% to the total flow volume. Shell tested the use of an anti-agglomerate LDHI on the
Popeye field in the Gulf of Mexico. For a production rate of 60 MMcf/d of gas, 3,000 b/d of
condensate and 430 b/d of water, 175 b/d of methanol was being injected. Less than one gallon
of LDHI was used per barrel of water in the test. Flow was maintained without hydrate formation
or increase in flow pressure. Following a 2 day flowline shut-in, restart was successful without
the need to inject methanol. Using LDHI production has increased to 100 MMcf/d with
associated water production up to 1,500 b/d. This will result in an increase in recoverable gas
reserves of 7.5 bcf. (Furlow, 2002; Anonymous, 2002).
3.6
Natural Gas STAR
Kerr-McGee is a participant in the US Environmental Protection Agency voluntary Natural Gas
STAR Program, which helps gas companies to identify cost effective methods to reduce
emissions of methane. The company was the Gas STAR Production Partner of the year in 2000
in recognition of its methane emission reduction achievements. Since joining in 1996 KerrMcGee has demonstrated a cumulative emission reduction of more than 8.5 Bcf, which includes
the period since 1992. Gas STAR participation has provided an extension of its environmental
program, which had already included best management practices. The creation of a recognized
recording method for past, current and future emission reductions is an important value provided
through Gas STAR participation (US EPA, 2001 a). The positive public recognition received is
highly prized by corporations.
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Other Gas STAR participants have also received recognition. Texaco Exploration and Production
has recorded 860,000 Mcf of emission reductions that saved $1.7 million over four years (EPA,
2000). Unocal Gulf Region similarly adopted the Gas STAR program as a pilot program and
demonstrated reductions of 640,000 Mcf over three years for savings of $1.9 million. The
success of the program has led to the adoption of methane emission reductions as a corporate
wide policy by Unocal Corporation (US EPA, 2001 b).
As Kerr-McGee has been the most successful of these three participants, their program is
described in more detail. Kerr-McGee first developed senior support for the program and
developed a company implementation plan. Activities were focussed on: identifying
opportunities to incorporate BMPs into new facilities; evaluation of the usefulness of BMPs at
older facilities; and completing inventories of past methane emission reduction activities.
Kerr-McGee communicated its commitment throughout the company and supports
implementation throughout its North American divisions with a centrally managed program. For
new facility construction or maintenance projects, the EH&S division works with project team
members to identify opportunities for implementation of Gas STAR BMPs and other pollution
prevention activities. Integration in the early design stages of emission reduction technologies
can save time and effort required to retrofit controls.
Kerr-McGee has determined that economic benefits result from emission reduction technologies
in 50 to 60% of new construction and maintenance retrofits. Although the company incorporates
control measures to be safe and responsible corporate citizens, the overall economic benefit of
emissions reductions is an important outcome. The average annual savings of $3.2 million has
resulted in a net savings from emission reductions of over $25 million (US).
The primary retrofits and process changes have been: use of vapour recovery units; installation
of flares; replacement of gas-actuated instruments with compressed air-actuated ones, and their
use in new installations; recapturing of Wilden pump vent gas; and installation of low-bleed
pneumatics in high emissions areas. (US EPA, 2001 a)
Details of this program not only demonstrate the benefits of government organized voluntary
programs, but also illustrate the benefits that companies recognize and gain from the public
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advertisement of results, especially when there are awards received. Non-financial benefits can
be part of the balance sheet in pollution prevention planning decisions.
3.7
Produced Water
The Troll C subsea water separation and injection system has been successfully piloted and
operated in the operation of Norwegian productions wells in 350 m of water (Horn and Soelvik,
2002). This first system separates water from the wellstream on the seafloor and re-injects it
through a dedicated well into a low pressure aquifer, which avoids transportation of the water
over the 3.3 km tie back to the main platform. Eight wells can be processed through the station,
although only 4 can be processed at one time. Over the first year of operation the injection rate
has gone from 2,000 m3/d to about 3,500 m3/d with peaks to 4,500 m3/d. Design capacity is
6,000 m3/d. With nearly 100% availability the station has injected about 1,000,000 m3 of
produced water with an oil content between 15 and 600 ppm.
3.8
Carbon Dioxide Injection and Sequestration
There is increasing interest in the sequestration of CO2 as part of the management of GHGs.
Possible sequestration locations are: the deep ocean; aquifers; oil reservoirs; and natural gas
reservoirs. Injection in oil producing formations provides enhanced oil recovery. Studies of CO2
injection for enhanced natural gas and condensate recovery are taking place as well as testing of
injection for coal bed methane production. An advantage of injection into hydrocarbon
formations is the expected sequestration period on the order of millions of years. Aquifer
injection may provide sequestration times in the order of a few thousands of years. Deep ocean
sequestration may retain the CO2 for periods of hundreds of years (Moritis, 2003).
Carbon dioxide injection has been used for enhanced recovery of oil since the 1970s. One project
in Canada receives CO2 at EnCana’s Weyburn oil production facility through a 328 km pipeline
from a North Dakota synfuel plant. Prior to this use the CO2 was vented through the coal to
methane process (Moritis, 2003).
Six UKOOA members, BP, ChevronTexaco, Shell, Agip, and EnCana, and are participating in a
Norwegian project to move CO2 to underground geological formations. In this, the first case of
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industrial scale CO2 sequestration in the world, CO2 has been injected in the Sleipner field in the
North Sea since 1996. The Sleipner produces significant amounts of CO2 along with natural gas.
The gas is captured at high pressure using an amine solvent and then injected into a saline
aquifer 1000 m below the seabed. Currently around 1 million tonnes of CO2 is injected per year,
which is roughly 3% of Norway's total emissions. A driver for this project is the existence of a
CO2-tax in Norway, making the compression and re-injection similar in cost to the discharge of
the gas.
Statoil also plans to reinject produced CO2 into an aquifer at a depth of 2,600 m beneath the
Snohvit development. CO2 at 5 to 8% in produced gas from three offshore fields will be
separated onshore and piped back to a subsea injection well (Moritis, 2003).
3.9
Design Approaches
Good pollution prevention includes the holistic consideration of the design of a project. One
Atlantic Canada operator uses a “brown paper” approach to exploration drilling projects. The
project team participates in a workshop session where multiple options are developed and the
team members broadly evaluate each option in a non-judgmental inclusive environment. This is a
brainstorming session where everything is on the table.
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4.0
Information Sources
4.1
References
ABB Gas Technology AS. 2003. Web page.
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Anonymous. 2002. Reducing Europe’s greenhouse gas emissions through CO2 capture and
reservoir storage. Offshore, October, 2002, p. 150.
Anonymous. 2002. Solving Deepwater Problems impact, Shell Global Solutions magazine, Issue
4, 2002, p. 17.
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Boudreaux, Clyde. 2002. Diesel-injection technology saves fuel, reduces emissions. Oil & Gas
Journal, Sept. 9, 2002, pp. 51, 52.
Canada-Newfoundland Offshore Petroleum Board, Canada-Nova Scotia Offshore Petroleum
Board and National Energy Board. 1999. Guidelines Respecting the Selection of Chemicals
Intended to be Used in Conjunction with Offshore Drilling and Production Activities in Frontier
Lands. January, 1999.
Canadian Association of Petroleum Producers. 2000. Global Climate Change Voluntary
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CEPA. 2003a. First Priority Substances List (PSL1): Chlorinated Wastewater Effluents,
Synopsis of Assessment Report
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CEPA. 2003b. Second Priority Substances List (PSL 2): Ethylene Glycol, Synopsis of
Assessment Report.
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Dillon Consulting Ltd. and BMT Cordah Ltd.2003. Standardizing the Reporting of Emissions to
Ambient Air From Atlantic Canadian Offshore Petroleum Activities. ESRF.
Dolphin News. 2001. Slender Well Initiative Gets Underway.
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EnCana Energy Corporation. 2002. Deep Panuke Offshore Gas Development, Comprehensive
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Furlow, William. 2002. LDHI advances enable longer tiebacks. Offshore Magazine. Sept. 2002,
pp. 56, 129.
Hibernia HS&E web pages
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Houghton, JT, LG Meira Filho, BA Callender, N Harris, A Kattenberg and K Maskell (Eds).
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Hull, Jennifer P.2002. MonoDiameter technology keeps hole diameter to TD. Offshore
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Horn, Terje and Nils Arne Soelvik. 2002. Troll C subsea separation station proves viability of
seafloor system, Offshore, November 2002, pp. 38-39.
Kvaerner Process Systems web page
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pdf
McKenna, E.A. et al. 1996. Comparing Ethylene Glycol (EG) and Propylene Glycol (PG) Using
Toxicity As a Basis for Risk Management Decisions, Summary of Meeting Paper. The 1996
Annual Meeting of the Society for Risk Analysis-Europe.
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Miles, Jonathan. 2001. Zero flaring can achieve operational, environmental benefits. Oil & Gas
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Mitchell, Iain, John Harcher and Guttorm Bentson. 2002. Deepwater slender well technology
cuts costs. Offshore Magazine, August 2002, pp. 65-66.
Moritis, Guntis.2003. CO2 sequestration adds new dimension to oil, gas production. Oil & Gas
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Mott MacDonald and Cordah. 2002. Options for the recycling and disposal of drill cuttings. A
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Newfoundland and Labrador Department of Environment. Pollution prevention. Web page.
www.gov.nf.ca/env/Env/pollution_prevention.asp
Nova Scotia Department of Environment and Labour. Nova Scotia Pollution Prevention
Program. Web page.
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National Energy Board, Canada-Newfoundland Offshore Petroleum Board, Canada-Nova Scotia
Offshore Petroleum Board. 2002. Offshore Waste Treatment Guidelines. August, 2002.
http://www.cnsopb.ns.ca/Regframework/regulatory.html
Ontario Ministry of Environment and Energy. 1993. Pollution Prevention Planning, Guidance
Document and Workbook, Queen’s Printer for Ontario, Toronto.
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OSPAR. 1992. 1992 OSPAR convention for the protection of the marine environment of the
North-East Atlantic. OSPAR commission, London.
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Offshore Activities. Annex 10 Reference no 1999-12. OSPAR Commission, London.
OSPAR. 2002 OSPAR decision 2000/2 on a Harmonised Mandatory Control System for the Use
and Reduction of the Discharge of Offshore Chemicals. OSPAR Commission London.
OSPAR. 2000. OSPAR decision 2000/3 on the use of organic-phase drilling fluids (OPF) and the
discharge of OPF-contaminated cuttings. OSPAR Commission London.
OSPAR. 2000. OSPAR Recommendation 2000/4 on a Harmonised Pre-Screening for Offshore
Chemicals. OSPAR Commission London.
OSPAR. 2000. OSPAR Recommendation 2000/5 on a Harmonised Offshore Chemical
Notification Format (HOCNF). OSPAR Commission London.
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Pacific Northwest Pollution Prevention Research Center. 1993. Pollution Prevention
Opportunities in Oil and Gas Production, Drilling and Exploration, Seattle, Wash.
PARCOM. 1992. PARCOM Decision 92/2 on the use of oil based muds. PARCOM London.
PTAC Petroleum Technology Alliance Canada. 2000. Downhole Gas/Water Separation and
Disposal Study: A Consumer Guide, Technology Information Session, Calgary, 2000/02/01 from
http://www.ptac.org/gas/gast0002.html
PTTC Petroleum Technology Transfer Council. 2000. Downhole Water Separation
Technologies. Notes from the workshop sponsored by PTTC’s Central Gulf Region, March 2,
2000, Baton Rouge, LA.
http://www.pttt.org/solutions/202.htm
Railroad Commission of Texas. 2001. Waste Minimization in the Oil Field. Austin, TX.
http://www.rrc.state.tx.us/divisions/og/key_programs/manual/wastemin.pdf
Stawaisz, R., S. Taylor, T. Hemphill, U. Tare, K. Morton and T. Valentine. 2003. Replacing oilbased with water-based drilling fluids, Offshore Magazine, February 2003, pp. 60, 61.
Sumrow, Mike. 2002a. Shell drills world’s first MonoDiameter well in South Texas. Oil & Gas
Journal, Oct. 21, 2002, pp. 53-55.
Sumrow, Mike. 2002b. CRA expandable tubulars create cased-hole production liner. Oil & Gas
Journal, Sept. 16, 2002, pp. 37-38.
Sumrow, Mike. 2002c. Synthetic-based muds reduce pollution discharge, improve drilling. Oil &
Gas Journal, Dec. 23, 2002, pp. 43-48.
Taylor, D.G. 2002. Operator’s Guide to Offshore Waste Treatment Guidelines for Canada’s
Offshore Areas – August 2002 Revision. Rev 3 of 3. D.G. Taylor, Inc. dtaylo[email protected]
- 55 -
Environmental Studies Research Funds
Pollution Prevention Opportunities
in the Offshore Oil and Gas Sector
March 2004
US EPA Office of Compliance. 2000. Profile of the Oil and Gas Extraction Industry, Sector
Notebook Project, Washington, D.C., EPA/310-R-006, October 2000.
US EPA. 2000a. Environmental Assessment of Final Effluent Limitations Guidelines and
Standards for Synthetic-Based Drilling Fluids and other Non-Aqueous Drilling Fluids in the Oil
and Gas Extraction Point Source Category. United States Environmental Protection Agency,
Office of Water, Washington, DC. EPA-821-B-00-014.
http://www.epa.gov/waterscience/guide/sbf/final/env.html
US EPA. 2000b. Development Document for Final Effluent Limitations Guidelines and
Standards for Synthetic-Based Drilling Fluids and other Non-Aqueous Drilling Fluids in the Oil
and Gas Extraction Point Source Category. United States Environmental Protection Agency,
Office of Water, Washington, DC. EPA-821-B-00-013
http://www.epa.gov/waterscience/guide/sbf/final/eng.html
US EPA. 2000. Texaco Exploration and Production, Inc. Natural Gas STAR Case Study Series.
United States Environmental Protection Agency, Air and Radiation (6202J), EPA430-F-00-010
June 2000
www.epa.gov/gasstar
US EPA. 2001 a. Kerr-McGee Natural Gas STAR Case Study Series. US Environmental
Protection Agency, Air and Radiation, EPA430-F-01-011, April 2001.
http://www.epa.gov/gasstar/pdf/kerrmcgee.pdf
US EPA. 2001 b. Unocal Gulf Region USA Natural Gas STAR Case Study Series, United States
Environmental Protection Agency, Air and Radiation (6202J), EPA430-F-01-012, February 2001
www.epa.gov/gasstar
US Environmental Protection Agency. 2001. Effluent Limitations Guidelines and New Source
Performance Standards for the Oil and Gas Extraction Point Source Category; OBM Approval
Under the Paperwork Reduction Act: Technical Amendment; Final Rule. Federal Register, 40
CFR Parts 9 and 435, Vol. 66, No. 14, Jan. 22, 2001, p. 6,850.
- 56 -
Environmental Studies Research Funds
Pollution Prevention Opportunities
in the Offshore Oil and Gas Sector
March 2004
White, Paul et al. 2002. Integrated fluids concept cuts costs and environmental impact in Cook
Inlet. Offshore Magazine, August 2002, pp. 56, 58.
4.2
Additional Resource Documents
http://www.atl.ec.gc.ca/epb/pollprev/loapic.html.
http://www.ec.gc.ca/NOPP/P2TUT/eg/indexe.html.
E&P Forum and UNEP IE. 1997. Environmental management in oil and gas exploration and
production. Oil Industry International Exploration and Production Forum (E&P Forum) and
United Nations Environment Programme Industry and Environment Centre (UNEP IE).
http://www.ogp.org.uk/pubs/254.pdf
E&P Forum. 1993. Exploration and Production (E&P) Waste Management Guidelines. London,
UK. Report No. 2.58/196.
http://www.ogp.org.uk/pubs/196.pdf
E&P reducing aromatics in produced water
http://www.ogp.org.uk/pubs/324.pdf
Lundquist, Robert and Mark Snyder. 1999. Minnesota Guide to Pollution Prevention Planning,
May 1999, 2nd Edition. Minnesota Technical Assistance Program, Minnesota Office of
Environmental Assistance, Minnesota Emergency Response Commission
http://www.moea.state.mn.us/publications/p2guid.pdf
National Energy Board, Canada-Newfoundland Offshore Petroleum Board, Canada-Nova Scotia
Offshore Petroleum Board. 2002. Offshore Waste Treatment Guidelines, August 2002,
Backgrounder.
http://www.cnopb.nfnet.com/publicat/guidelin/owtgl/eng/owbg0208.pdf
- 57 -
Environmental Studies Research Funds
Pollution Prevention Opportunities
in the Offshore Oil and Gas Sector
March 2004
Ohio Pollution Prevention and Waste Minimization Planning Guidance Manual September 30,
1993, State of Ohio Environmental Protection Agency, Office of Pollution Prevention
http://www.epa.state.oh.us/opp/guide/p2pbgn.html
RCC. 2001. Waste Minimization in the Oil Field. Railroad Commission of Texas, Oil and Gas
Division. Austin, TX.
http://www.rrc.state.tx.us/divisions/og/key-programs/manual/
RRC. 1998. Waste Minimization, User Guide - A Software Tool to Aid Waste Minimization
Planning. Oil and Gas Division and Information Technology Services Division (12/02/98),
Railroad Commission of Texas
http://www.rrc.state.tx.us/divisions/og/key-programs/userguide/GUIDE.HTML
US EPA. 2000. Profile of the Oil and Gas Extraction Industry. EPA Office of Compliance Sector
Notebook Project. U.S. Environmental Protection Agency, Washington, DC. EPA/310-R-99006.
http://www.epa.gov/compliance/resources/publications/assistance/sectors/notebooks/oil.html
US EPA. 1992. Facility Pollution Prevention Guide, EPA/600/R-92/088. Office of Solid Waste,
U.S. Environmental Protection Agency, Washington, D.C.
4.3
Additional Web Resources
Nova Scotia Department of Environment and Labour. Web site.
http://www.gov.ns.ca/enla/rmep/p2/
Canadian Council of Ministers of the Environment (CCME). Web site.
http://www.ccme.ca/initiatives/pollution.html
Canadian Centre for Pollution Prevention. Web site.
http://www.c2p2online.com/
- 58 -
Environmental Studies Research Funds
Pollution Prevention Opportunities
in the Offshore Oil and Gas Sector
March 2004
Environment Canada, Canadian Pollution Prevention Information Clearinghouse. Web site.
http://www.ec.gc.ca/cppic/en/index.cfm
National Research Council of Canada. 2003. Design for Environment Guide. Web site.
http://dfe-sce.nrc-cnrc.gc.ca/overview/overview_e.html
Pollution Prevention World Information Network (P2.WIN). Web site.
http://www.p2win.org/
U.S. EPA. Pollution Prevention Information Clearinghouse (PPIC). Web site.
http://www.epa.gov/opptintr/library/ppicindex.htm
U.S. EPA. Enviro$en$e. Web site.
http://es.epa.gov/
U.S. EPA. Design for the Environment (DfE)
http://www.epa.gov/opptintr/dfe/index.htm
Massachusetts Toxics Use Reduction Institute. P2 GEMS. Web site.
http://www.p2gems.org/p2
4.4
Contact Information for Organizations Consulted
in Preparing the Document
Personal Communications
David Burley, Manager, Environmental Affairs, C-NOPB, Phone: (709) 778-1403
Mike Coolen, Director of East Coast Operations, Canadian Superior Energy Inc., Phone: (902)
474-3960
- 59 -
Environmental Studies Research Funds
Pollution Prevention Opportunities
in the Offshore Oil and Gas Sector
March 2004
Andre d'Entremont, Health, Safety and Environmental Coordinator, Kerr-McGee Offshore
Canada Ltd., Phone: (902) 423-8857
Stephen Full, Environmental Analyst, East Coast Operations, Encana Resources, Phone: (902)
422-5574.
Doug Gregory, Manager, East Coast Operations, Shell Canada Limited, Phone: (902) 474-2001
Doug Hollett, Manager, Atlantic Canada, Business Development, Marathon Canada Limited,
Phone: (902) 423-3950
Geoffrey V. Hurley, Senior Environmental Analyst, Loss Management, East Coast Operations,
EnCana Resources, Phone: (902) 474-5350
Jim MacDonald, Frontier Drilling Supervisor; Shell Canada Ltd., Phone: (902) 474-2000.
Francine Power, Petro-Canada Offshore Development & Operations, Phone: (709) 778-3500.
Cal Ross, ExxonMobil Canada Ltd., Phone: (902) 490-8900.
David Taylor, Husky Energy, Phone: (709) 724-3900.
Urban Williams, Senior Environmental Advisor, Terra Nova Project, Petro-Canada Offshore
Development & Operations, Phone: (709) 778-3764.
Tom Windeyer, EnCana Resources, Phone: (902)b 492-4500.
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Appendix A
Operator’s Guide to Offshore Waste Treatment
Guidelines for Canada’s Offshore Areas
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