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USACE / NAVFAC / AFCEC / NASA UFGS-26 42 14.00 10 (August 2008)

---------------------------------

Preparing Activity: USACE Superseding

UFGS-26 42 14 00 10 (November 2006)

UNIFIED FACILITIES GUIDE SPECIFICATIONS

References are in agreement with UMRL dated January 2016

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SECTION TABLE OF CONTENTS

DIVISION 26 - ELECTRICAL

SECTION 26 42 14.00 10

CATHODIC PROTECTION SYSTEM (SACRIFICIAL ANODE)

08/09

PART 1 GENERAL

1.1 REFERENCES

1.2 SUBMITTALS

1.3 QUALITY ASSURANCE

1.3.1 Services of "Corrosion Expert"

1.3.2 Isolators

1.3.3 Anode and Bond Wires

1.3.4 Surge Protection

1.3.5 Nonmetallic Pipe System

1.3.5.1 Coatings

1.3.5.2 Tracer Wire

1.3.6 Drawings

1.4 DELIVERY, STORAGE, AND HANDLING

1.5 EXTRA MATERIALS

PART 2 PRODUCTS

2.1 SYSTEM DESCRIPTION

2.1.1 Contractor's Modifications

2.1.2 Summary of Services Required

2.1.3 Tests of Components

2.1.4 Electrical Potential Measurements

2.1.5 Achievement of Criteria for Protection

2.1.6 Metallic Components on Nonmetallic Systems and Typicals

2.1.6.1 Metallic Components

2.1.6.2 Fire Hydrants

2.1.6.3 Pipe Under Concrete Slab

2.1.6.4 Valves

2.1.6.5 Metallic Pipe Component or Section

2.1.6.6 Connectors or Change-of-Direction Devices

2.1.7 Metallic Component Coating

2.2 MAGNESIUM ANODES

2.2.1 Anode Composition

2.2.2 Dimensions and Weights

2.2.3 Packaged Anodes

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2.2.4 Zinc Anodes

2.2.5 Connecting Wire

2.2.5.1 Wire Requirements

2.2.5.2 Anode Header Cable

2.3 MISCELLANEOUS MATERIALS

2.3.1 Electrical Wire

2.3.1.1 Wire Splicing

2.3.1.2 Test Wires

2.3.1.3 Resistance Wire

2.3.2 Conduit

2.3.3 Test Boxes and Junctions Boxes

2.3.4 Joint, Patch, Seal, and Repair Coating

2.3.5 Backfill Shields

2.3.6 Epoxy Potting Compound

2.3.7 Test Stations

2.3.8 Joint and Continuity Bonds

2.3.9 Resistance Bonds

2.3.10 Stray Current Measurements

2.3.11 Electrical Isolation of Structures

2.3.11.1 Electrically Isolating Pipe Joints

2.3.11.2 Electrically Conductive Couplings

2.3.11.3 Insulating Joint Testing

2.3.12 Underground Structure Coating

2.3.12.1 Field Joints

2.3.12.2 Inspection of Pipe Coatings

2.3.12.2.1 Protective Covering for Aboveground Piping System

2.3.12.2.2 Ferrous Surfaces

2.3.13 Resistance Wire

2.3.14 Electrical Connections

2.3.15 Electrical Tape

2.3.16 Permanent Reference Electrodes

2.3.17 Casing

PART 3 EXECUTION

3.1 CRITERIA OF PROTECTION

3.1.1 Iron and Steel

3.1.2 Aluminum

3.1.3 Copper Piping

3.2 TRENCHING AND BACKFILLING

3.3 INSTALLATION

3.3.1 Anode Installation

3.3.1.1 Single Anodes

3.3.1.2 Groups of Anodes

3.3.1.3 Welding Methods

3.3.2 Anode Placement - General

3.3.3 Underground Pipeline

3.3.4 Installation Details

3.3.5 Lead Wire Connections

3.3.5.1 Underground Pipeline (Metallic)

3.3.5.2 Resistance Wire Splices

3.3.6 Location of Test Stations

3.3.7 Underground Pipe Joint Bonds

3.4 ELECTRICAL ISOLATION OF STRUCTURES

3.4.1 Isolation Joints and Fittings

3.4.2 Gas Distribution Piping

3.5 TESTS AND MEASUREMENTS

3.5.1 Baseline Potentials

3.5.2 Isolation Testing

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3.5.2.1 Insulation Checker

3.5.2.2 Cathodic Protection Meter

3.5.3 Anode Output

3.5.4 Reference Electrode Potential Measurements

3.5.5 Location of Measurements

3.5.5.1 Piping or Conduit

3.5.5.2 Tanks

3.5.5.3 Casing Tests

3.5.5.4 Interference Testing

3.5.5.5 Holiday Test

3.5.5.6 Recording Measurements

3.6 TRAINING COURSE

3.7 SYSTEM TESTING

3.8 SEEDING

3.9 CLEANUP

-- End of Section Table of Contents --

SECTION 26 42 14.00 10 Page 3

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USACE / NAVFAC / AFCEC / NASA UFGS-26 42 14.00 10 (August 2008)

---------------------------------

Preparing Activity: USACE Superseding

UFGS-26 42 14 00 10 (November 2006)

UNIFIED FACILITIES GUIDE SPECIFICATIONS

References are in agreement with UMRL dated January 2016

**************************************************************************

SECTION 26 42 14.00 10

CATHODIC PROTECTION SYSTEM (SACRIFICIAL ANODE)

08/09

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NOTE: This guide specification covers the requirements for a cathodic protection system utilizing continuous flow direct current from sacrificial anodes.

Adhere to UFC 1-300-02 Unified Facilities Guide

Specifications (UFGS) Format Standard when editing this guide specification or preparing new project specification sections. Edit this guide specification for project specific requirements by adding, deleting, or revising text. For bracketed items, choose applicable items(s) or insert appropriate information.

Remove information and requirements not required in respective project, whether or not brackets are present.

Comments, suggestions and recommended changes for this guide specification are welcome and should be

submitted as a Criteria Change Request (CCR).

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PART 1 GENERAL

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NOTE: This specification covers a cathodic protection system for metal surfaces against corrosion by producing a continuous flow of direct current from sacrificial anodes to the metal to be protected. The anodes should be of sufficient size and quantity to protect the buried metal items for a specified number of years before replacement. The

U.S. Department of Transportation has issued regulations requiring the application of cathodic protection to natural gas pipelines, liquid natural gas pipelines, petroleum pipelines, petroleum products pipelines, liquid petroleum gas pipelines, and petroleum storage facilities. Title 49 of the

Code of Federal Regulations, Parts 191, 192, 193 and

SECTION 26 42 14.00 10 Page 4

195 should be consulted for applicable cathodic protection requirements for specific applications.

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1.1 REFERENCES

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NOTE: This paragraph is used to list the publications cited in the text of the guide specification. The publications are referred to in the text by basic designation only and listed in this paragraph by organization, designation, date, and title.

Use the Reference Wizard's Check Reference feature when you add a RID outside of the Section's

Reference Article to automatically place the reference in the Reference Article. Also use the

Reference Wizard's Check Reference feature to update the issue dates.

References not used in the text will automatically be deleted from this section of the project specification when you choose to reconcile references in the publish print process.

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The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

ASTM B418

ASTM INTERNATIONAL (ASTM)

(2012) Standard Specification for Cast and

Wrought Galvanic Zinc Anodes

ASTM B843

ASTM D1248

(2013) Standard Specification for

Magnesium Alloy Anodes for Cathodic

Protection

(2012) Standard Specification for

Polyethylene Plastics Extrusion Materials for Wire and Cable

NACE INTERNATIONAL (NACE)

NACE RP0193 (2001) External Cathodic Protection of

On-Grade Carbon Steel Storage Tank Bottoms

NACE SP0169

NACE SP0177

NACE SP0188

(2013) Control of External Corrosion on

Underground or Submerged Metallic Piping

Systems

(2014) Mitigation of Alternating Current and Lightning Effects on Metallic

Structures and Corrosion Control Systems

(1999; R 2006) Discontinuity (Holiday)

Testing of New Protective Coatings on

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projects, a code of up to three characters within the submittal tags may be used following the "G" designation to indicate the approving authority.

Codes for Army projects using the Resident

Management System (RMS) are: "AE" for

Architect-Engineer; "DO" for District Office

(Engineering Division or other organization in the

District Office); "AO" for Area Office; "RO" for

Resident Office; and "PO" for Project Office. Codes following the "G" typically are not used for Navy,

Air Force, and NASA projects.

An "S" following a submittal item indicates that the submittal is required for the Sustainability

Notebook to fulfill federally mandated sustainable requirements in accordance with Section 01 33 29

SUSTAINABILITY REPORTING.

Choose the first bracketed item for Navy, Air Force and NASA projects, or choose the second bracketed item for Army projects.

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Government approval is required for submittals with a "G" designation; submittals not having a "G" designation are for [Contractor Quality Control approval.] [information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the

Government.] Submittals with an "S" are for inclusion in the

Sustainability Notebook, in conformance to Section 01 33 29 SUSTAINABILITY

REPORTING. Submit the following in accordance with Section 01 33 00

SUBMITTAL PROCEDURES:

SD-02 Shop Drawings

Drawings; G[, [_____]]

Contractor's Modifications; G[, [_____]]

SD-03 Product Data

Equipment; G[, [_____]]

Spare Parts

SD-06 Test Reports

Tests and Measurements; G[, [_____]]

Contractor's Modifications; G[, [_____]]

SD-07 Certificates

Cathodic Protection System

Services of "Corrosion Expert"; G[, [_____]]

SD-10 Operation and Maintenance Data

Cathodic Protection System; G[, [_____]]

Training Course; G[, [_____]]

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projects, a code of up to three characters within the submittal tags may be used following the "G" designation to indicate the approving authority.

Codes for Army projects using the Resident

Management System (RMS) are: "AE" for

Architect-Engineer; "DO" for District Office

(Engineering Division or other organization in the

District Office); "AO" for Area Office; "RO" for

Resident Office; and "PO" for Project Office. Codes following the "G" typically are not used for Navy,

Air Force, and NASA projects.

An "S" following a submittal item indicates that the submittal is required for the Sustainability

Notebook to fulfill federally mandated sustainable requirements in accordance with Section 01 33 29

SUSTAINABILITY REPORTING.

Choose the first bracketed item for Navy, Air Force and NASA projects, or choose the second bracketed item for Army projects.

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Government approval is required for submittals with a "G" designation; submittals not having a "G" designation are for [Contractor Quality Control approval.] [information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the

Government.] Submittals with an "S" are for inclusion in the

Sustainability Notebook, in conformance to Section 01 33 29 SUSTAINABILITY

REPORTING. Submit the following in accordance with Section 01 33 00

SUBMITTAL PROCEDURES:

SD-02 Shop Drawings

Drawings; G[, [_____]]

Contractor's Modifications; G[, [_____]]

SD-03 Product Data

Equipment; G[, [_____]]

Spare Parts

SD-06 Test Reports

Tests and Measurements; G[, [_____]]

Contractor's Modifications; G[, [_____]]

SD-07 Certificates

Cathodic Protection System

Services of "Corrosion Expert"; G[, [_____]]

SD-10 Operation and Maintenance Data

Cathodic Protection System; G[, [_____]]

Training Course; G[, [_____]]

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1.3 QUALITY ASSURANCE

1.3.1 Services of "Corrosion Expert"

Obtain the services of a "corrosion expert" to supervise, inspect, and test the installation and performance of the cathodic protection system.

"Corrosion expert" refers to a person, who by thorough knowledge of the physical sciences and the principles of engineering and mathematics, acquired by professional education and related practical experience, is qualified to engage in the practice of corrosion control of buried or submerged metallic surfaces.

a. Such a person must be accredited or certified by the National

Association of Corrosion Engineers (NACE) as a NACE Accredited

Corrosion Specialist or a NACE certified Cathodic Protection (CP)

Specialist or be a registered professional engineer who has certification or licensing that includes education and experience in corrosion control of buried or submerged metallic piping and tank systems, if such certification or licensing includes 5 years experience in corrosion control on underground metallic surfaces of the type under this contract.

b. The "corrosion expert" shall make at least 3 visits to the project site. The first of these visits shall include obtaining soil resistivity data, acknowledging the type of pipeline coatings to be used and reporting to the Contractor the type of cathodic protection required. Once the submittals are approved and the materials delivered, the "corrosion expert" shall revisit the site the ensure the

Contractor understands installation practices and laying out the components. The third visit shall involve testing the installed cathodic protection systems and training applicable personnel on proper maintenance techniques. The "corrosion expert" shall supervise installation and testing of all cathodic protection.

c. Submit evidence of qualifications of the "corrosion expert" including its name and qualifications certified in writing to the Contracting

Officer prior to the start of construction. Certification shall be submitted giving the name of the firm, the number of years of experience, and a list of not less than five (5) of the firm's installations, three (3) or more years old, that have been tested and found satisfactory.

1.3.2 Isolators

Isolators are required to insulate the indicated pipes from any other structure. Isolators shall be provided with lightning protection and a test station as shown.

1.3.3 Anode and Bond Wires

A minimum of [5] [8] [25] [_____] magnesium anodes with an unpackaged weight of [_____] kg pounds shall be provided uniform distances along the metallic pipe lines. A minimum of [3] [5] [10] [_____] test stations shall be used for these anodes. These anodes shall be in addition to anodes for the pipe under concrete slab and casing requirements. For each cathodic system, the metallic components and structures to be protected shall be made electrically continuous. This shall be accomplished by installing bond wires between the various structures. Bonding of existing buried structures may also be required to preclude detrimental stray current

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effects and safety hazards. Provisions shall be included to return stray current to its source without damaging structures intercepting the stray current. The electrical isolation of underground facilities in accordance with acceptable industry practice shall be included under this section.

All tests shall be witnessed by the Contracting Officer.

1.3.4 Surge Protection

Approved zinc grounding cells or sealed weatherproof lightning arrestor devices shall be installed across insulated flanges or fittings installed in underground piping as indicated on the drawings. The arrestor shall be gapless, self-healing, solid state type. Zinc anode composition shall conform to ASTM B418, Type II. Lead wires shall be number 6 AWG copper with high molecular weight polyethylene (HMWPE) insulation. The zinc grounding cells shall not be prepackaged in backfill but shall be installed as detailed on the drawings. Lightning arrestors or zinc grounding cells are not required for insulated flanges on metallic components used on nonmetallic piping systems.

1.3.5 Nonmetallic Pipe System

In the event pipe other than metallic pipe is approved and used in lieu of metallic pipe, all metallic components of this pipe system shall be protected with cathodic protection. Detailed drawings of cathodic protection for each component shall be submitted to the Contracting Officer for approval within 45 days after date of receipt of notice to proceed, and before commencement of any work.

1.3.5.1 Coatings

Coatings for metallic components shall be as required for metallic fittings. Protective covering (coating and taping) shall be completed and tested on each metallic component (such as valves, hydrants and fillings).

This covering shall be as required for underground metallic pipe. Each test shall be witnessed by the Contracting Officer. Coatings shall be selected, applied, and inspected as specified in these specifications. The use of nonmetallic pipe does not change other requirements of the specifications. Any deviations due to the use of nonmetallic pipe shall be submitted for approval.

1.3.5.2 Tracer Wire

When a nonmetallic pipe line is used to extend or add to an existing metallic line, an insulated No. 8 AWG copper wire shall be thermit-welded to the existing metallic line and run the length of the new nonmetallic line. This wire shall be used as a locator tracer wire and to maintain continuity to any future extensions of the pipe line.

1.3.6 Drawings

Submit [six] [_____] copies of detail drawings consisting of a complete list of equipment and material including manufacturer's descriptive and technical literature, catalog cuts, results of system design calculations including soil-resistivity, installation instructions and certified test data showing location of anodes and stating the maximum recommended anode current output density. Include in the detail drawings complete wiring and schematic diagrams, insulated fittings, test stations, permanent reference cells, and bonding.and any other details required to demonstrate that the system has been coordinated and will function properly as a unit.

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Locations shall be referenced to two (2) permanent facilities or mark points.

1.4 DELIVERY, STORAGE, AND HANDLING

Storage area for magnesium anodes will be designated by the Contracting

Officer. If anodes are not stored in a building, tarps or similar protection should be used to protect anodes from inclement weather.

Packaged anodes, damaged as a result of improper handling or being exposed to rain, shall be resacked and the required backfill added.

1.5 EXTRA MATERIALS

After approval of shop drawings, and not later than three (3) months prior to the date of beneficial occupancy, furnish spare parts data for each different item of material and equipment specified, after approval of detail drawings and not later than six (6) months prior to the date of beneficial occupancy. The data shall include a complete list of parts, special tools, and supplies, with current unit prices and source of supply. One (1) spare anode of each type shall be furnished. In addition, supply information for material and equipment replacement for all other components of the complete system, including anodes, cables, splice kits and connectors, corrosion test stations, and any other components not listed above. [Furnish a reference cell on a reel with 120 m 350 feet of conductor, along with other accessories, and a digital voltmeter that can be used in the maintenance of this cathodic protection system. Use of this equipment shall be demonstrated in actual tests during the training course, which shall include a description of the the equipment and measurement of the pipe-to-soil potential, rainfall, and gas company voltages.]

PART 2 PRODUCTS

2.1 SYSTEM DESCRIPTION

Provide a complete, operating, sacrificial anode cathodic protection system in complete compliance with NFPA 70, with all applicable Federal, State, and local regulations and with the minimum requirements of this contract.

a. In addition to the minimum requirements of these specifications,

[construction of gas pipelines and associated cathodic protection systems shall be in compliance with 49 CFR 192] [and] [construction of hazardous liquid pipelines, including fuel pipelines, and associated cathodic protection systems shall be in compliance with 49 CFR 195]

[and] [construction and installation of underground fuel storage tanks and associated cathodic protection system shall be in compliance with

40 CFR 280].

b. The services required include planning, installation, adjusting and testing of a cathodic protection system, using sacrificial anodes for cathodic protection of the [Water] [Fire Protection] [Force Main] [Gas]

[_____] lines, their connectors and [lines under the slab or floor foundation.] The cathodic protection system shall include anodes, cables, connectors, corrosion protection test stations, and any other equipment required for a complete operating system providing the NACE criteria of protection as specified.

c. Submit an itemized list of equipment and materials including item number, quantity, and manufacturer of each item, within [30] [_____] days after receipt of notice to proceed. The list shall be accompanied

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by a description of procedures for each type of testing and adjustments, including testing of coating for thickness and holidays.

Installation of materials and equipment shall not commence until this submittal is approved. Insulators are required whenever needed to insulate the pipes from any other structure. Any pipe crossing the

[_____] pipe shall have a test station. The cathodic protection shall be provided on [Water] [Fire Protection] [Force Main] [Gas] [_____] pipes.

d. Submit proof that the materials and equipment furnished under this section conform to the specified requirements contained in the referenced standards or publications. The label or listing by the specified agency will be acceptable evidence of such compliance.

e. Before final acceptance of the cathodic protection system, submit [6]

[_____] copies of operating manuals outlining the step-by-step procedures required for system startup, operation, adjustment of current flow, and shutdown. The manuals shall include the manufacturer's name, model number, service manual, parts list, and brief description of all equipment and their basic operating features.

f. Submit [6] [_____] copies of maintenance manuals, listing routine maintenance procedures, recommendation for maintenance testing, possible breakdowns and repairs, and troubleshooting guides. The manuals shall include single-line diagrams for the system as installed; instructions in making pipe-to-reference cell and tank-to-reference cell potential measurements and frequency of monitoring; instructions for dielectric connections, interference and sacrificial anode bonds; instructions shall include precautions to ensure safe conditions during repair of pipe or other metallic systems. The instructions shall be neatly bound between permanent covers and titled "Operating and

Maintenance Instructions." These instructions shall be submitted for the Contracting Officer's approval. The instructions shall include the following:

(1) As-built drawings, to scale, of the entire system, showing the locations of the piping, location of all anodes and test stations, locations of all insulating joints, and structure-to-soil potential test points as measured during the tests required by paragraph TESTS AND MEASUREMENTS. Each test point shall be given a unique alphanumeric identification that is cross referenced to the data sheets.

(2) Recommendations for maintenance testing, including instructions in making pipe-to-reference cell potential measurements and frequency of testing.

(3) All maintenance and operating instructions and nameplate data shall be in English.

(4) Instructions shall include precautions to insure safe conditions during repair of pipe system.

2.1.1 Contractor's Modifications

The specified system is based on a complete system with magnesium sacrificial anodes. The Contractor may modify the cathodic protection system after review of the project, site verification, and analysis, if the proposed modifications include the anodes specified and will provide better

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Nominal Weight

(kg) (lbs)

TYPICAL MAGNESIUM ANODE SIZE

(Cross sections may be round, square, or D shaped)

Approx. Size (mm)

(inch)

Nominal Gross Weight

(kg) (lbs) Packaged in Backfill

Nominal Package Dimensions

(mm) (inch)

22.750

178 X 178 X 4067 X 7 X

16

45.5100

254 X 61010 X 24

2.2.3 Packaged Anodes

Provide anodes in packaged form with the anode surrounded by specially-prepared quick-wetting backfill and contained in a water permeable cloth or paper sack. Anodes shall be centered by means of spacers in the backfill material. The backfill material shall have the following composition, unless otherwise indicated:

Material Approximate Percent by Weight

Gypsum 75

Bentonite

Sodium Sulphate

Total

20

5

100

2.2.4 Zinc Anodes

Zinc anodes shall conform to ASTM B418, Type II.

2.2.5 Connecting Wire

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NOTE: Any pinhole, cut, scratch or other damage to the anode cable exposing bare copper to the electrolyte will result in early failure of the cathodic protection system. For this reason, special, extra heavy insulation is used on anode cable. While it is often expedient to use the same type wire for the cathodic (negative) cable in order to avoid a mix-up in the field, the cathode cable is not subject to anodic failure and lesser insulation can be used.

Type RHW-2-USE-2 insulation should be used under hot asphalt.

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2.2.5.1 Wire Requirements

Wire shall be No. [12] [10] [_____] AWG solid copper wire, not less than 3 m

10 feet long, unspliced, complying with NFPA 70, Type [TW] [RHW-USE] insulation. [Connecting wires for magnesium anodes shall be factory installed with the place or emergence from the anode in a cavity sealed

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flush with a dielectric sealing compound.] [Connecting wires for zinc anodes shall be factory installed with the place of connection to the protruding steel core completely sealed with a dielectric material.]

2.2.5.2 Anode Header Cable

Cable for anode header and distribution shall be No. [_____] AWG stranded copper wire with type CP high molecular weight polyethylene, 2.8 mm 7/64 inch thick insulation, 600-volt rating.

2.3 MISCELLANEOUS MATERIALS

2.3.1 Electrical Wire

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NOTE: The cathodic protection system will fail unless full consideration is given to specifications for electrically insulating pipe joints, electrically conductive pipe joints, and casing cradles and seals. Mechanical and electrical specifications should reference paragraphs

"Electrically Isolating Pipe Joints" and

"Electrically Conductive Couplings."

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Wire shall be No. [12] [10] [_____] AWG stranded copper wire with NFPA 70,

Type [TW] [RHW-USE with outer covering] [RHW-USE] [Polyethylene] [_____] insulation. Polyethylene insulation shall comply with the requirements of

ASTM D1248 and shall be of the following types, classes, and grades:

High-molecular weight polyethylene shall be Type I, Class C, Grade E5.

High-density polyethylene shall be Type III, Class C, Grade E3.

2.3.1.1 Wire Splicing

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NOTE: In water tanks, split bolts are used (above the water line only) because working space is limited and the hydraulic or mechanical compression tools may be cumbersome and hazardous to use; since single split-bolt will work loose when the wires it connects are moved, minimum of two split bolts should be used. At ground level or in trenches, compression tools can be used conveniently, and the swaged sleeve connection produced by such tools is more reliable than split bolts.

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Connecting wire splicing shall be made with copper compression connectors or exothermic welds, following instructions of the manufacturer. Single split-bolt connections shall not be used. Sheaths for encapsulating electrical wire splices to be buried underground shall fit the insulated wires entering the spliced joints and epoxy potting compound shall be as specified below.

2.3.1.2 Test Wires

Test wires shall be AWG No. 12 stranded copper wire with NFPA 70, Type TW

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a. Connection of new metallic piping or components to existing piping.

b. Pressure piping under floor slab to a building.

Isolation shall be provided at metallic connection of all lines to existing system and where connecting to a building. Additionally, isolation shall be provided between [water] [_____] and/or [gas] [_____] [forced main] line; and foreign pipes that cross the new lines within 3.05 m 10 feet.

Isolation fittings, including isolating flanges and couplings, shall be installed aboveground or in a concrete pit.

2.3.11.1 Electrically Isolating Pipe Joints

Electrically isolating pipe joints shall be of a type that is in regular factory production.

2.3.11.2 Electrically Conductive Couplings

Electrically conductive couplings shall be of a type that has a published maximum electrical resistance rating given in the manufacturer's literature. Cradles and seals shall be of a type that is in regular factory production made for the purpose of electrically insulating the carrier pipe from the casing and preventing the incursion of water into the annular space.

2.3.11.3 Insulating Joint Testing

A Model 601 Insulation Checker, as manufactured by ["Gas Electronics"],

[_____], [or] [an approved equal], shall be used for insulating joint

(flange) electrical testing.

2.3.12 Underground Structure Coating

This coating specification shall take precedence over any other project specification and drawing notes, whether stated or implied, and shall also apply to the pipeline or tank supplier. No variance in coating quality shall be allowed by the Contractor or Base Construction Representative without the written consent of the designer. All underground metallic pipelines and tanks to be cathodically protected shall be afforded a good quality factory-applied coating. This includes all carbon steel, cast-iron and ductile-iron pipelines or vessels. Coatings shall be selected, applied, and inspected as specified. If non-metallic pipelines are installed, all metallic fittings on pipe sections shall be coated in accordance with this specification section.

a. The nominal thickness of the metallic pipe joint or other component coating shall be [0.2][0.4][0.6][1.0][1.5][_____] mm

[8][16][24][40][60][_____] mils, plus or minus 5 percent.

b. Pipe and joint coating for factory applied or field repair material shall be applied as recommended by the manufacturer and shall be one of the following:

(1) Continuously extruded polyethylene and adhesive coating system.

(2) Polyvinyl chloride pressure-sensitive adhesive tape.

(3) High density polyethylene/bituminous rubber compound tape.

(4) Butyl rubber tape.

(5) Coal tar epoxy.

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2.3.12.1 Field Joints

All field joints shall be coated with materials compatible with the pipeline coating compound. The joint coating material shall be applied to an equal thickness as the pipeline coating. Unbonded coatings shall not be used on these buried metallic components. This includes the elimination of all unbonded polymer wraps or tubes. Once the pipeline or vessel is set in the trench, an inspection of the coating shall be conducted. This inspection shall include electrical holiday detection. Any damaged areas of the coating shall be properly repaired. The Contracting Officer shall be asked to witness inspection of the coating and testing using a holiday detector.

2.3.12.2 Inspection of Pipe Coatings

Any damage to the protective covering during transit and handling shall be repaired before installation. After field coating and wrapping has been applied, the entire pipe shall be inspected by an electric holiday detector with impressed current in accordance with NACE SP0188 using a full-ring, spring-type coil electrode. The holiday detector shall be equipped with a bell, buzzer, or other type of audible signal which sounds when a holiday is detected. All holidays in the protective covering shall be repaired immediately upon detection. Occasional checks of holiday detector potential will be made by the Contracting Officer's representative to determine suitability of the detector. All labor, materials, and equipment necessary for conducting the inspection shall be furnished by the

Contractor.

2.3.12.2.1 Protective Covering for Aboveground Piping System

Finish painting shall conform to the applicable paragraph of SECTION:

09 90 00 PAINTS AND COATINGS and as follows:

2.3.12.2.2 Ferrous Surfaces

Shop-primed surfaces shall be touched-up with ferrous metal primer.

Surfaces that have not been shop-primed shall be solvent-cleaned. Surfaces that contain loose rust, loose mil scale, and other foreign substances shall be mechanically-cleaned by power wire-brushing and primed with ferrous metal primer. Primed surface shall be finished with two (2) coats of exterior oil paint and vinyl paint. Coating for each entire piping service shall be an approved pipe line wrapping having a minimum coating resistance of 50,000 Ohms per 0.0929 square meters square foot.

2.3.13 Resistance Wire

Wire shall be No. 16 or No. 22 nickel-chromium wire with TW insulation.

2.3.14 Electrical Connections

Electrical connections shall be done as follows: a. Exothermic welds shall be ["Cadweld",] [" Bundy",] ["Thermoweld",] [or]

[an approved equal]. Use of this material shall be in strict accordance with the manufacturer's recommendations.

b. Electrical-shielded arc welds shall be approved for use on steel pipe by shop drawing submittal action.

SECTION 26 42 14.00 10 Page 21

Nominal Weight

(kg) (lbs)

TYPICAL MAGNESIUM ANODE SIZE

(Cross sections may be round, square, or D shaped)

Approx. Size (mm)

(inch)

Nominal Gross Weight

(kg) (lbs) Packaged in Backfill

Nominal Package Dimensions

(mm) (inch)

22.750

178 X 178 X 4067 X 7 X

16

45.5100

254 X 61010 X 24

2.2.3 Packaged Anodes

Provide anodes in packaged form with the anode surrounded by specially-prepared quick-wetting backfill and contained in a water permeable cloth or paper sack. Anodes shall be centered by means of spacers in the backfill material. The backfill material shall have the following composition, unless otherwise indicated:

Material Approximate Percent by Weight

Gypsum 75

Bentonite

Sodium Sulphate

Total

20

5

100

2.2.4 Zinc Anodes

Zinc anodes shall conform to ASTM B418, Type II.

2.2.5 Connecting Wire

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NOTE: Any pinhole, cut, scratch or other damage to the anode cable exposing bare copper to the electrolyte will result in early failure of the cathodic protection system. For this reason, special, extra heavy insulation is used on anode cable. While it is often expedient to use the same type wire for the cathodic (negative) cable in order to avoid a mix-up in the field, the cathode cable is not subject to anodic failure and lesser insulation can be used.

Type RHW-2-USE-2 insulation should be used under hot asphalt.

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2.2.5.1 Wire Requirements

Wire shall be No. [12] [10] [_____] AWG solid copper wire, not less than 3 m

10 feet long, unspliced, complying with NFPA 70, Type [TW] [RHW-USE] insulation. [Connecting wires for magnesium anodes shall be factory installed with the place or emergence from the anode in a cavity sealed

SECTION 26 42 14.00 10 Page 16

flush with a dielectric sealing compound.] [Connecting wires for zinc anodes shall be factory installed with the place of connection to the protruding steel core completely sealed with a dielectric material.]

2.2.5.2 Anode Header Cable

Cable for anode header and distribution shall be No. [_____] AWG stranded copper wire with type CP high molecular weight polyethylene, 2.8 mm 7/64 inch thick insulation, 600-volt rating.

2.3 MISCELLANEOUS MATERIALS

2.3.1 Electrical Wire

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NOTE: The cathodic protection system will fail unless full consideration is given to specifications for electrically insulating pipe joints, electrically conductive pipe joints, and casing cradles and seals. Mechanical and electrical specifications should reference paragraphs

"Electrically Isolating Pipe Joints" and

"Electrically Conductive Couplings."

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Wire shall be No. [12] [10] [_____] AWG stranded copper wire with NFPA 70,

Type [TW] [RHW-USE with outer covering] [RHW-USE] [Polyethylene] [_____] insulation. Polyethylene insulation shall comply with the requirements of

ASTM D1248 and shall be of the following types, classes, and grades:

High-molecular weight polyethylene shall be Type I, Class C, Grade E5.

High-density polyethylene shall be Type III, Class C, Grade E3.

2.3.1.1 Wire Splicing

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NOTE: In water tanks, split bolts are used (above the water line only) because working space is limited and the hydraulic or mechanical compression tools may be cumbersome and hazardous to use; since single split-bolt will work loose when the wires it connects are moved, minimum of two split bolts should be used. At ground level or in trenches, compression tools can be used conveniently, and the swaged sleeve connection produced by such tools is more reliable than split bolts.

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Connecting wire splicing shall be made with copper compression connectors or exothermic welds, following instructions of the manufacturer. Single split-bolt connections shall not be used. Sheaths for encapsulating electrical wire splices to be buried underground shall fit the insulated wires entering the spliced joints and epoxy potting compound shall be as specified below.

2.3.1.2 Test Wires

Test wires shall be AWG No. 12 stranded copper wire with NFPA 70, Type TW

SECTION 26 42 14.00 10 Page 17

or RHW-USE with outer covering or polyethylene insulation.

2.3.1.3 Resistance Wire

Resistance wire shall be AWG No. 16 or No. 22 nickel-chromium wire.

2.3.2 Conduit

Rigid galvanized steel conduit and accessories shall conform to UL 6. Non metallic conduit shall conform to NEMA TC 2.

2.3.3 Test Boxes and Junctions Boxes

Boxes shall be outdoor type conforming to UL 514A.

2.3.4 Joint, Patch, Seal, and Repair Coating

Sealing and dielectric compound shall be a black, rubber based compound that is soft, permanently pliable, tacky, moldable, and unbacked. Compound shall be applied as recommended by the manufacturer, but not less than 13 mm

1/2-inch thick. Coating compound shall be [cold-applied coal-tar base mastic] [hot-applied coal-tar enamel]. Pressure-sensitive vinyl plastic electrical tape shall conform to UL 510.

2.3.5 Backfill Shields

Shields shall consist of approved pipeline wrapping or fiberglass-reinforced, coal-tar impregnated tape, or plastic weld caps, specifically made for the purpose and installed in accordance with the manufacturer's recommendations. When joint bonds are required, due to the use of mechanical joints, the entire joint shall be protected by the use of a kraft paper joint cover. The joint cover shall be filled with poured-in, hot coat-tar enamel.

2.3.6 Epoxy Potting Compound

Compound for encapsulating electrical wire splices to be buried underground shall be a two package system made for the purpose.

2.3.7 Test Stations

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NOTE: Retain bracketed sentences only when nonmetallic materials are used in the project.

**************************************************************************

Stations shall be of the [aboveground] [flush-curb-box type] and shall be the standard product of a recognized manufacturer. Test stations shall be complete with an insulated terminal block having the required number of terminals. The test station shall be provided with a lockable over and shall have an embossed legend, "C.P. Test." A minimum of one (1) test station shall be provided each component of the [pipe] [tank] [_____]. A minimum of six (6) terminals shall be provided in each test station. A minimum of two (2) leads are required to the metallic pipe from each test station. Other conductors shall be provided for each anode, other foreign pipe, and reference cells as required. [Test stations may be constructed of nonmetallic materials. However, if nonmetallic materials are utilized, as a minimum, the materials shall be resistant to damage from ultraviolet radiation, contain good color retention qualities, contain high strength

SECTION 26 42 14.00 10 Page 18

NOTE: The cathodic protection system will fail unless full engineering considerations are applied to selection, location and installation of electrically conductive joints and electrically isolating joints including the use of underground type dielectric coatings (not paint).

Adequate electrical conductivity of a pipe joint made by means other than welding should be determined by a "corrosion expert." The "corrosion expert" must be accredited or certified by the

National Association of Corrosion Engineers (NACE) as a NACE Accredited Corrosion Specialist or a NACE certified Cathodic Protection (CP) Specialist or be a registered professional engineer who has certification or licensing that includes education and experience in corrosion control. Allowable electrical resistance depends on the cross sectional area of the pipe metal, the resistivity of the pipe metal, and the effectiveness of the coating on the pipe. Effectively coated pipe underground requires only a fraction of the electrical conductivity at joints needed for bare pipe. Shop painted pipe is considered to be the same as bare pipe and is not to be confused with pipe coated with an underground type dielectric coating.

The type of electrical isolating pipe joint to be used requires engineering design consideration. In general, the dielectric parts of an isolating joint will not withstand structural or environmental stresses as well as an all-metal type of joint. If the pipe on the cathodic protected side of the underground electrically isolating pipe joint, including the joint, is not effectively coated, interference type corrosion may occur unless other measures are taken. Factors to be considered include: a. Deflection stresses b. Pull-out stresses c. Expansion-contraction due to temperature changes d. Is function as a union necessary?

e. Is field assembly of critical parts practical?

f. Hazardous locations to be avoided g. Accessibility if above ground h. Location of test box if below ground i. Importance of coating the adjacent pipe if below ground j. Vulnerability to short circuiting

SECTION 26 42 14.00 10 Page 26

Factor of safety on pull-out strength required has to be engineered for the specific conditions involved since no blanket provisions are fully applicable to all cases. The requirement for isolating flanges or couplings should be based on a study of the conditions. If the new piping is a short extension to an existing old piping system not under cathodic protection, an isolating fitting should be installed at the point of connection, since the new piping will be anodic to the older system. If the older system is under cathodic protection, no isolating fitting should be used.

**************************************************************************

3.4.1 Isolation Joints and Fittings

Isolating fittings, including main line isolating flanges and couplings, shall be installed aboveground, or within manholes, wherever possible.

Where isolating joints must be covered with soil, they shall be fitted with a paper joint cover specifically manufactured for covering the particular joint, and the space within the cover filled with hot coal-tar enamel.

Isolating fittings in lines entering buildings shall be located at least

305 mm 12 inch above grade of floor level, when possible. Isolating joints shall be provided with grounding cells to protect against over-voltage surges or approved surge protection devices. The cells shall provide a low resistance across isolating joint without excessive loss of cathodic current.

3.4.2 Gas Distribution Piping

Electrical isolation shall be provided at each building riser pipe to the pressure regulator, at all points where a short to another structure or to a foreign structure may occur, and at other locations as indicated on the drawings.

3.5 TESTS AND MEASUREMENTS

Submit test reports in booklet form tabulating all field tests and measurements performed, upon completion and testing of the installed system and including close interval potential survey, casing and interference tests, final system test verifying protection, insulated joint and bond tests, and holiday coating test. Submit a certified test report showing that the connecting method has passed a 120-day laboratory test without failure at the place of connection, wherein the anode is subjected to maximum recommended current output while immersed in a three percent sodium chloride solution.

3.5.1 Baseline Potentials

Each test and measurement will be witnessed by the Contracting Officer.

Notify the Contracting Officer a minimum of five (5) working days prior to each test. After backfill of the [pipe] [tank], the static potential-to-soil of the [pipe] [tank] shall be measured. The locations of these measurements shall be identical to the locations specified for

[pipe-] [tank-] to-reference electrode potential measurements. The initial measurements shall be recorded.

SECTION 26 42 14.00 10 Page 27

2.3.12.1 Field Joints

All field joints shall be coated with materials compatible with the pipeline coating compound. The joint coating material shall be applied to an equal thickness as the pipeline coating. Unbonded coatings shall not be used on these buried metallic components. This includes the elimination of all unbonded polymer wraps or tubes. Once the pipeline or vessel is set in the trench, an inspection of the coating shall be conducted. This inspection shall include electrical holiday detection. Any damaged areas of the coating shall be properly repaired. The Contracting Officer shall be asked to witness inspection of the coating and testing using a holiday detector.

2.3.12.2 Inspection of Pipe Coatings

Any damage to the protective covering during transit and handling shall be repaired before installation. After field coating and wrapping has been applied, the entire pipe shall be inspected by an electric holiday detector with impressed current in accordance with NACE SP0188 using a full-ring, spring-type coil electrode. The holiday detector shall be equipped with a bell, buzzer, or other type of audible signal which sounds when a holiday is detected. All holidays in the protective covering shall be repaired immediately upon detection. Occasional checks of holiday detector potential will be made by the Contracting Officer's representative to determine suitability of the detector. All labor, materials, and equipment necessary for conducting the inspection shall be furnished by the

Contractor.

2.3.12.2.1 Protective Covering for Aboveground Piping System

Finish painting shall conform to the applicable paragraph of SECTION:

09 90 00 PAINTS AND COATINGS and as follows:

2.3.12.2.2 Ferrous Surfaces

Shop-primed surfaces shall be touched-up with ferrous metal primer.

Surfaces that have not been shop-primed shall be solvent-cleaned. Surfaces that contain loose rust, loose mil scale, and other foreign substances shall be mechanically-cleaned by power wire-brushing and primed with ferrous metal primer. Primed surface shall be finished with two (2) coats of exterior oil paint and vinyl paint. Coating for each entire piping service shall be an approved pipe line wrapping having a minimum coating resistance of 50,000 Ohms per 0.0929 square meters square foot.

2.3.13 Resistance Wire

Wire shall be No. 16 or No. 22 nickel-chromium wire with TW insulation.

2.3.14 Electrical Connections

Electrical connections shall be done as follows: a. Exothermic welds shall be ["Cadweld",] [" Bundy",] ["Thermoweld",] [or]

[an approved equal]. Use of this material shall be in strict accordance with the manufacturer's recommendations.

b. Electrical-shielded arc welds shall be approved for use on steel pipe by shop drawing submittal action.

SECTION 26 42 14.00 10 Page 21

c. Brazing shall be as specified in Paragraph: Lead Wire Connections.

2.3.15 Electrical Tape

Pressure-sensitive vinyl plastic electrical tape shall conform to UL 510.

2.3.16 Permanent Reference Electrodes

Permanent reference electrodes shall be Cu-CuS04 electrodes suitable for direct burial. Electrodes shall be guaranteed by the supplier for 15 years' service in the environment in which they shall be placed.

Electrodes shall be installed directly beneath pipe, or metallic component.

2.3.17 Casing

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NOTE: This paragraph will be deleted if mechanical and electrical specifications include these requirements.

**************************************************************************

Where a pipeline is installed in a casing under a roadway or railway, the pipeline shall be electrically insulated from the casing, and the annular space sealed and filled with an approved corrosion inhibiting product against incursion of water.

PART 3 EXECUTION

3.1 CRITERIA OF PROTECTION

Acceptance criteria for determining the adequacy of protection on a buried underground [pipe] [tank] [metallic component] shall be in accordance with [

NACE SP0169] [NACE RP0193] [NACE SP0285] and as specified below.

3.1.1 Iron and Steel

The following method a. shall be used for testing cathodic protection voltages. If more than one method is required, method b. shall be used.

a. A negative voltage of at least minus 850 millivolts as measured between the underground component and a saturated copper-copper sulphate reference electrode connecting the earth (electrolyte) directly over the underground component. Determination of this voltage shall be made with the cathodic protection system in operation. Voltage drops shall be considered for valid interpretation of this voltage measurement. A minimum of minus 850 millivolts "instant off" potential between the underground component being tested and the reference cell shall be achieved over 95 percent of the area of the structure. Adequate number of measurements shall be obtained over the entire structure, pipe, tank, or other metallic component to verify and record achievement of minus 850 millivolts "instant off." This potential shall be obtained over 95 percent of the total metallic area without the "instant off" potential exceeding 1200 millivolts.

b. A minimum polarization voltage shift of 100 millivolts as measured between the underground component and a saturated copper-copper sulphate reference electrode contacting the earth directly over the underground component. This polarization voltage shift shall be determined by interrupting the protective current and measuring the

SECTION 26 42 14.00 10 Page 22

polarization decay. When the protective current is interrupted, an immediate voltage shift will occur. The voltage reading, after the immediate shift, shall be used as the base reading from which to measure polarization decay. Measurements achieving 100 millivolts decay shall be made over 95 percent of the metallic surface being protected.

c. For any metallic component, a minimum of four (4) measurements shall be made using subparagraph a., above, and achieving the "instant off" potential of minus 850 millivolts. Two (2) measurements shall be made over the anodes and two (2) measurements shall be made at different locations near the component and farthest away from the anode.

3.1.2 Aluminum

Aluminum underground component shall not be protected to a potential more negative than minus 1200 millivolts, measured between the underground component and a saturated copper-copper sulphate reference electrode contacting the earth, directly over the metallic component. Resistance, if required, shall be inserted in the anode circuit within the test station to reduce the potential of the aluminum to a value which will not exceed a potential more negative than minus 1200 millivolts. Voltage shift criterion shall be a minimum negative polarization shift of 100 millivolts measured between the metallic component and a saturated copper-copper sulphate reference electrode contacting the earth, directly over the metallic component. The polarization voltage shift shall be determined as outlined for iron and steel.

3.1.3 Copper Piping

For copper piping, the following criteria shall apply: A minimum of 100 millivolts of cathodic polarization between the structure surface and a stable reference electrode contacting the electrolyte. The polarization voltage shift shall be determined as outlined for iron and steel.

3.2 TRENCHING AND BACKFILLING

Perform trenching and backfilling in accordance with [Section 31 00 00

EARTHWORK] [_____]. In the areas of the anode beds, all trees and underbrush shall be cleared and grubbed to the limits shown or indicated.

In the event rock is encountered in providing the required depth for anodes, determine an alternate approved location and, if the depth is still not provided, submit an alternate plan to the Contracting Officer.

Alternate techniques and depths must be approved prior to implementation.

3.3 INSTALLATION

3.3.1 Anode Installation

Unless otherwise authorized, installation shall not proceed without the presence of the Contracting Officer. Anodes of the size specified shall be installed to the depth indicated and at the locations shown. Locations may be changed to clear obstructions with the approval of the Contracting

Officer. Anodes shall be installed in sufficient number and of the required type, size, and spacing to obtain a uniform current distribution over the surface of the structure. The anode system shall e designed for a life of 25 years of continuous operation. Anodes shall be installed as indicated in a dry condition after any plastic or waterproof protective covering has been completely removed from the water permeable, permanent

SECTION 26 42 14.00 10 Page 23

container housing the anode metal. The anode connecting wire shall not be used for lowering the anode into the hole. The annular space around the anode shall be backfilled with fine earth in 150 mm 6 inch layers and each layer shall be hand tamped. Care must be exercised not to strike the anode or connecting wire with the tamper. Approximately 20 L 5 gallons of water shall be applied to each filled hole after anode backfilling and tamping has been completed to a point about 150 mm 6 inch above the anode. After the water has been absorbed by the earth, backfilling shall be completed to the ground surface level.

3.3.1.1 Single Anodes

Single anodes, spaced as shown, shall be [connected] [connected through a test station] to the pipeline, allowing adequate slack in the connecting wire to compensate for movement during backfill operation.

3.3.1.2 Groups of Anodes

Groups of anodes, in quantity and location shown, shall be connected to an anode header cable. The anode header cable shall make contact with the structure to be protected only through a test station. Anode lead connection to the anode header cable shall be made by an approved crimp connector or exothermic weld and splice mold kit with appropriate potting compound.

3.3.1.3 Welding Methods

Connections to [ferrous pipe] [metal tanks] shall be made by exothermic weld methods manufactured for the type of [pipe] [tank] supplied. Electric arc welded connections and other types of welded connections to ferrous pipe and structures shall be approved before use.

3.3.2 Anode Placement - General

Packaged anodes shall be installed completely dry, and shall be lowered into holes by rope sling or by grasping the cloth gather. The anode lead wire shall not be used in lowering the anodes. The hole shall be backfilled with fine soil in 150 mm 6 inch layers and each layer shall be hand-tamped around the anode. Care must be exercised not to strike the anode or lead wire with the tamper. If immediate testing is to be performed, water shall be added only after backfilling and tamping has been completed to a point 150 mm 6 inch above the anode. Approximately 8 L 2 gallons of water may be poured into the hole. After the water has been absorbed by the soil, backfilling and tamping may be completed to the top of the hole. Anodes shall be installed as specified or shown. In the event a rock strata is encountered prior to achieving specified augered-hole depth, anodes may be installed horizontally to a depth at least as deep as the bottom of the pipe, with the approval of the

Contracting Officer.

3.3.3 Underground Pipeline

Anodes shall be installed at a minimum of 2.5 m 8 feet and a maximum of 3 m

10 feet from the line to be protected.

3.3.4 Installation Details

Details shall conform to the requirements of this specification. Details shown on the drawings are indicative of the general type of material

SECTION 26 42 14.00 10 Page 24

required, and are not intended to restrict selection to material of any particular manufacturer.

3.3.5 Lead Wire Connections

3.3.5.1 Underground Pipeline (Metallic)

To facilitate periodic electrical measurements during the life of the sacrificial anode system and to reduce the output current of the anodes, if required, all anode lead wires shall be connected to a test station and buried a minimum of 610 mm 24 inch in depth. The cable shall be No. 10

AWG, stranded copper, polyethylene or RHW-USE insulated cable. The cable shall make contact with the structure only through a test station.

Resistance wire shall be installed between the cable and the pipe cable, in the test station, to reduce the current output, if required. Anode connections, except in the test station, shall be made with exothermic welding process, and shall be insulated by means of at least three (3) layers of electrical tape; and all lead wire connections shall be installed in a moistureproof splice mold kit and filled with epoxy resin. Lead wire-to-structure connections shall be accomplished by an exothermic welding process. All welds shall be in accordance with the manufacturer's recommendations. A backfill shield filled with a pipeline mastic sealant or material compatible with the coating shall be placed over the weld connection and shall be of such diameter as to cover the exposed metal adequately.

3.3.5.2 Resistance Wire Splices

Resistance wire connections shall be accomplished with silver solder and the solder joints wrapped with a minimum of three (3) layers of pressure-sensitive tape. Lead wire connections shall be installed in a moistureproof splice mold kit and filled with epoxy resin.

3.3.6 Location of Test Stations

Test stations shall be of the type and location shown and shall be [curb box] [post] [indoor] mounted. Provide buried insulating joints with test wire connections brought to a test station. Reference all test stations with GPS coordinates. Unless otherwise shown, locate other test stations as follows: a. At 300 m 1,000-foot intervals or less.

b. Where the pipe or conduit crosses any other metal pipe.

c. At both ends of casings under roadways and railways.

d. Where both sides of an insulating joint are not accessible above ground for testing purposes.

3.3.7 Underground Pipe Joint Bonds

Underground pipe having other than welded or threaded coupling joints shall be made electrically continuous by means of a bonding connection installed across the joint.

3.4 ELECTRICAL ISOLATION OF STRUCTURES

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SECTION 26 42 14.00 10 Page 25

NOTE: The cathodic protection system will fail unless full engineering considerations are applied to selection, location and installation of electrically conductive joints and electrically isolating joints including the use of underground type dielectric coatings (not paint).

Adequate electrical conductivity of a pipe joint made by means other than welding should be determined by a "corrosion expert." The "corrosion expert" must be accredited or certified by the

National Association of Corrosion Engineers (NACE) as a NACE Accredited Corrosion Specialist or a NACE certified Cathodic Protection (CP) Specialist or be a registered professional engineer who has certification or licensing that includes education and experience in corrosion control. Allowable electrical resistance depends on the cross sectional area of the pipe metal, the resistivity of the pipe metal, and the effectiveness of the coating on the pipe. Effectively coated pipe underground requires only a fraction of the electrical conductivity at joints needed for bare pipe. Shop painted pipe is considered to be the same as bare pipe and is not to be confused with pipe coated with an underground type dielectric coating.

The type of electrical isolating pipe joint to be used requires engineering design consideration. In general, the dielectric parts of an isolating joint will not withstand structural or environmental stresses as well as an all-metal type of joint. If the pipe on the cathodic protected side of the underground electrically isolating pipe joint, including the joint, is not effectively coated, interference type corrosion may occur unless other measures are taken. Factors to be considered include: a. Deflection stresses b. Pull-out stresses c. Expansion-contraction due to temperature changes d. Is function as a union necessary?

e. Is field assembly of critical parts practical?

f. Hazardous locations to be avoided g. Accessibility if above ground h. Location of test box if below ground i. Importance of coating the adjacent pipe if below ground j. Vulnerability to short circuiting

SECTION 26 42 14.00 10 Page 26

Factor of safety on pull-out strength required has to be engineered for the specific conditions involved since no blanket provisions are fully applicable to all cases. The requirement for isolating flanges or couplings should be based on a study of the conditions. If the new piping is a short extension to an existing old piping system not under cathodic protection, an isolating fitting should be installed at the point of connection, since the new piping will be anodic to the older system. If the older system is under cathodic protection, no isolating fitting should be used.

**************************************************************************

3.4.1 Isolation Joints and Fittings

Isolating fittings, including main line isolating flanges and couplings, shall be installed aboveground, or within manholes, wherever possible.

Where isolating joints must be covered with soil, they shall be fitted with a paper joint cover specifically manufactured for covering the particular joint, and the space within the cover filled with hot coal-tar enamel.

Isolating fittings in lines entering buildings shall be located at least

305 mm 12 inch above grade of floor level, when possible. Isolating joints shall be provided with grounding cells to protect against over-voltage surges or approved surge protection devices. The cells shall provide a low resistance across isolating joint without excessive loss of cathodic current.

3.4.2 Gas Distribution Piping

Electrical isolation shall be provided at each building riser pipe to the pressure regulator, at all points where a short to another structure or to a foreign structure may occur, and at other locations as indicated on the drawings.

3.5 TESTS AND MEASUREMENTS

Submit test reports in booklet form tabulating all field tests and measurements performed, upon completion and testing of the installed system and including close interval potential survey, casing and interference tests, final system test verifying protection, insulated joint and bond tests, and holiday coating test. Submit a certified test report showing that the connecting method has passed a 120-day laboratory test without failure at the place of connection, wherein the anode is subjected to maximum recommended current output while immersed in a three percent sodium chloride solution.

3.5.1 Baseline Potentials

Each test and measurement will be witnessed by the Contracting Officer.

Notify the Contracting Officer a minimum of five (5) working days prior to each test. After backfill of the [pipe] [tank], the static potential-to-soil of the [pipe] [tank] shall be measured. The locations of these measurements shall be identical to the locations specified for

[pipe-] [tank-] to-reference electrode potential measurements. The initial measurements shall be recorded.

SECTION 26 42 14.00 10 Page 27

3.5.2 Isolation Testing

Before the anode system is connected to the [pipe] [tank], an isolation test shall be made at each isolating joint or fitting. This test shall demonstrate that no metallic contact, or short circuit exists between the two isolated sections of the [pipe] [tank]. Any isolating fittings installed and found to be defective shall be reported to the Contracting

Officer.

3.5.2.1 Insulation Checker

A Model 601 insulation checker, as manufactured by ["Gas Electronics",]

[_____] [or] [an approved equal], using the continuity check circuit, shall be used for isolating joint (flange) electrical testing. Testing shall conform to the manufacturer's operating instructions. Test shall be witnessed by the Contracting Officer. An isolating joint that is good will read full scale on the meter. If an isolating joint is shorted, the meter pointer will be deflected or near zero on the meter scale. Location of the fault shall be determined from the instructions, and the joint shall be repaired. If an isolating joint is located inside a vault, the pipe shall be sleeved with insulator when entering and leaving the vault.

3.5.2.2 Cathodic Protection Meter

A Model B3A2 cathodic protection meter, as manufactured by ["M.C. Miller",]

[_____] [or] [an approved equal], using the continuity check circuit, shall be used for isolating joint (flange) electrical testing. This test shall be performed in addition to the Model 601 insulation checker. Continuity is checked across the isolation joint after the test lead wire is shorted together and the meter adjusted to scale. A full-scale deflection indicates the system is shorted at some location. The Model 601 verifies that the particular insulation under test is good and the Model B3A2 verifies that the system is isolated. If the system is shorted, further testing shall be performed to isolate the location of the short.

3.5.3 Anode Output

As the anodes or groups of anodes are connected to the [pipe] [tank]

[_____], current output shall be measured with an approved clamp-on milliammeter, calibrated shunt with a suitable millivoltmeter or multimeter, or a low resistance ammeter. (Of the three methods, the low-resistance ammeter is the least desirable and most inaccurate. The clamp-on milliammeter is the most accurate.) The values obtained and the date, time, and location shall be recorded.

3.5.4 Reference Electrode Potential Measurements

Upon completion of the installation and with the entire cathodic protection system in operation, electrode potential measurements shall be made using a copper-copper sulphate reference electrode and a potentiometer-voltmeter, or a direct-current voltmeter having an internal resistance (sensitivity) of not less than 10 megohms per volt and a full scale of 10 volts. The locations of these measurements shall be identical to the locations used for baseline potentials. The values obtained and the date, time, and locations of measurements shall be recorded. No less than eight (8) measurements shall be made over any length of line or component.

Additional measurements shall be made at each distribution service riser, with the reference electrode placed directly over the service line.

SECTION 26 42 14.00 10 Page 28

3.5.5 Location of Measurements

3.5.5.1 Piping or Conduit

For coated piping or conduit, measurements shall be taken from the reference electrode located in contact with the earth, directly over the pipe. Connection to the pipe shall be made at service risers, valves, test leads, or by other means suitable for test purposes. Pipe-to-soil potential measurements shall be made at intervals not exceeding [1.5] [3]

[_____] m [5] [10] [_____] feet. The Contractor may use a continuous pipe-to-soil potential profile in lieu of 1.5 m 5 foot interval pipe-to-soil potential measurements. Additional measurements shall be made at each distribution service riser, with the reference electrode placed directly over the service line adjacent to the riser. Potentials shall be plotted versus distance to an approved scale. Locations where potentials do not meet or exceed the criteria shall be identified and reported to the

Contracting Officer's representative.

3.5.5.2 Tanks

For underground tanks, at least [6] [_____] measurements shall be taken from the reference electrode located: a. Directly over the center of the tank.

b. At a point directly over the tank and midway between each pair of anodes.

3.5.5.3 Casing Tests

Before final acceptance of the installation, the electrical separation of carrier pipe from casings shall be tested and any short circuits corrected.

3.5.5.4 Interference Testing

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NOTE: Adverse effects may be caused by the foreign pipeline.

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Before final acceptance of the installation, interference tests shall be made with respect to any foreign [pipes] [tanks] in cooperation with the owner of the foreign [pipes] [tanks]. A full report of the tests giving all details shall be made. Stray current measurements shall be performed at all isolating locations and at locations where the new pipeline crosses foreign metallic pipes; results of stray current measurements shall also be submitted for approval. The method of measurements and locations of measurements shall be submitted for approval. As a minimum, stray current measurements shall be performed at the following locations: a. Connection point of new pipeline to existing pipeline.

b. Crossing points of new pipeline with existing lines.

3.5.5.5 Holiday Test

Any damage to the protective covering during transit and handling shall be repaired before installation. After field-coating and wrapping has been applied, the entire pipe shall be inspected by an electric holiday detector

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with impressed current in accordance with NACE SP0188 using a full-ring, spring-type coil electrode. The holiday detector shall be equipped with a bell, buzzer, or other type of audible signal which sounds when a holiday is detected. Holidays in the protective covering shall be repaired upon detection. Occasional checks of holiday detector potential will be made by the Contracting Officer to determine suitability of the detector. Labor, materials, and equipment necessary for conducting the inspection shall be furnished by the Contractor. The coating system shall be inspected for holes, voids, cracks, and other damage during installation.

3.5.5.6 Recording Measurements

All [pipe-] [tank-] [_____] to-soil potential measurements, including initial potentials where required, shall be recorded. Locate, correct and report to the Contracting Officer any short circuits to foreign [pipes]

[tanks] [_____] encountered during checkout of the installed cathodic protection system. [Pipe-] [Tank-] [_____] to-soil potential measurements shall be taken on as many [pipes] [tanks] [_____] as necessary to determine the extent of protection or to locate short-circuits.

3.6 TRAINING COURSE

Conduct a training course for the operating staff as designated by the

Contracting Officer. The training period shall consist of a total of [4]

[8] [_____] hours of normal working time and shall start after the system is functionally completed but prior to final acceptance tests. Submit the proposed Training Course Curriculum (including topics and dates of discussion) indicating that all of the items contained in the operating and maintenance instructions, as well as demonstrations of routine maintenance operations, including testing procedures included in the maintenance instructions, are to be covered. The field instructions shall cover all of the items contained in the operating and maintenance instructions, as well as demonstrations of routine maintenance operations, including testing procedures included in the maintenance instructions. At least 14 days prior to date of proposed conduction of the training course, the training course curriculum shall be submitted for approval, along with the proposed training date. Training shall consist of demonstration of test equipment, providing forms for test data and the tolerances which indicate that the system works.

3.7 SYSTEM TESTING

Submit a report including potential measurements taken at adequately-close intervals to establish that minus 850 millivolts potential, "instant-off" potential, is provided, and that the cathodic protection is not providing interference to other foreign pipes causing damage to paint or pipes. The report shall provide a narrative describing how the criteria of protection is achieved without damaging other pipe or structures in the area.

3.8 SEEDING

Seeding shall be done as directed, in all unsurfaced locations disturbed by this construction. In areas where grass cover exists, it is possible that sod can be carefully removed, watered, and stored during construction operations, and replaced after the operations are completed since it is estimated that no section of pipeline should remain uncovered for more than two (2) days. The use of sod in lieu of seeding shall require approval by the Contracting Officer.

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3.9 CLEANUP

The Contractor is responsible for cleanup of the construction site. All paper bags, wire clippings, etc., shall be disposed of as directed. Paper bags, wire clippings and other waste shall not be put in bell holes or anodes excavation.

-- End of Section --

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