cathodic protection guidance 3

8/10/2019 Cathodic Protection Guidance 3

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Cathodic Protection Guidance?Cathodic Protection Guidance?

Who needs that?Who needs that?ArenArent NACE & STI enough?t NACE & STI enough?

David RobinettDavid RobinettVirginia Dept. ofVirginia Dept. of

Environmental QualityEnvironmental Quality


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December 22,1998 CP required for USTsDecember 22,1998 CP required for USTs

CP required for USTs

Huge demand for CP professionals

some well qualified

some not so well qualified some qualified, but overloaded with work

No CP experts on staff, then or now

Our job is to determine CP compliance 6,500 out of 22,000 USTs


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December 1998 CP required for USTsDecember 1998 CP required for USTs

Owners in need of CP services In a hurry

Dont want to spend too much

May not know a lot about what they are buying

Just want to be in compliance with the UST regs

Inspection time comes (a year or 5 later) Records of installation? (CP expert signature)

System testing performed?

Some CP test report examples:


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-0.1062

volts


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6.2 Volts

4.5 Volts


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8.7 MA8.6 MA

9.1 MA

8.9 MA


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8.7 mV

8.6 mV

9.1 mV

8.9 mV


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Helping our Tank OwnersHelping our Tank Owners

First attempts Reference UST Regs, NACE & STI publications

Inconsistencies among staff

Varying interpretations (ambiguity) in publications

Resulted in a number of inadequate installationsand questionable test reports from industry

Second attempt

Developed a CP test form (January 2003)

This Helped!!!


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1

2

3

4

IN THE SPACE BELOW, SKETCH THE IMPORTANT PARTS OF THE FACILITY SUCH AS TANKS, MAN WAYS, VENTS,

ANODES, PUMP ISLANDS AND BUILDINGS. INDICATE REFERENCE CELL LOCATIONS USING LOCATION CODE "R" AND

SEQUENTIAL NUMBERS ( R1, R2, AND R3 ).

COMMENTS

VENT RISER

FLEX

CONNECTOR

PIPING

RISER(CONTINUOUS, ISOLATED)

TANK

No.

FILL

RISER

TANK

BOTTOM

STP

RISER

FACILITY NAME: FAC. ID # :

CONTINUITY TEST

DATE OF TEST:


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Helping our Tank OwnersHelping our Tank Owners

Third attempt-Develop a CP Manual

Review existing state publications (choseMississippi:2002)

Reinforce as much of NACE & STI as possible

Include definitions, certification requirements, basics of CP Educate and Re-educate staff members

Study Remote CP readings (K. Henderson, LUSTline #48)

Discuss Draft amongst ourselves a couple of times


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CP ManualCP Manual pointspoints--ofof--clarityclarity

1. General guidelines for CP National Standard (e.g., NACE) must be

followed

2. CP Tester qualifications defined and referenced (NACE & EPA)

3. Soil access must be provided - No readings over concrete or asphalt

per NACE RP0285

4. IR (voltage) drops considered and instant-off tests required for all

impressed current systems5. Continuity/isolation must always be established when testing :

Point-to-Point and Fixed CellMoving Ground methods reviewed.

6. CP Expert consultation required under certain circumstances

Example: CP Expert must resolve inconclusive test results (nosecond testers opinion)


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CP ManualCP Manual pointspoints--ofof--clarityclarity continuedcontinued

7. Test criteria:

-850mV-On for factory-installed galvanic anode systems (sti-P3)(never for impressed current)

-850mV-Off for impressed current and field installed galvanicinterruptible systems

100mV Polarization for interruptible galvanic and impressed currentsystems

8. Number of Test points:

Galvanic or STI-P3 3 test points (one local, one remote, & oneoptional location)

Impressed Current 3 tests (all local over the structure noremotes)

9. Reference cell placement locations must always be included on thesite sketch of the CP test/evaluation form

10. Flex connectors in contact with the ground must have the groundmoved away or be CP protected


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Finalize GuidanceFinalize Guidance Draft out to industry for review

Virginias CP Manual published May 2006

Weblink address:http://www.deq.virginia.gov/tanks/pdf/06-2006.pdf

cathodic protection guidance 3

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