Cathodic Protection Guidance? Cathodic Protection Guidance? Who needs that?Who needs that?

ArenAren’’t NACE & STI enough?t NACE & STI enough?

David Robinett David Robinett –– Virginia Dept. of Virginia Dept. of Environmental QualityEnvironmental Quality

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

December 1998 CP required for USTsDecember 1998 CP required for USTs

• Owners in need of CP services• In a hurry• Don’t 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:

-0.1062

volts

6.2 Volts

4.5 Volts

8.7 MA

8.6 MA

9.1 MA

8.9 MA

8.7 mV

8.6 mV

9.1 mV

8.9 mV

Help for usHelp for us

• Formal Corrosion Courses• STI• Appalachian Underground Corrosion Short Course

• OUST Compendium• Started April 6, 1989• Made available on the website ~ December 1998

• Other States• CP professionals

• Contractors• CP Experts

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 installations

and questionable test reports from industry

• Second attempt• Developed a CP test form (January 2003)• This Helped!!!

Inst. Off (R1)

Inst. Off (R2)

1234

1234

CATHODIC PROTECTION TEST FORM

ZIP:LONG:LAT:

_________________________________________________ SIGNATURE OF PERSON CONDUCTING TEST

TESTER NAME:SOURCE OF CERTIFICATION:

STRUCTURE PASSED OR FAILED TO MEET THE MINIMUM NACE STANDARD

OUTLINED IN RP0285-95

STRUCTURE CONTACT POINT FINAL

VOLTAGEVOLTAGE

DECAYPIPI

NG

#

REFERENCE CELL POTENTIAL @

STRUCTURE PASSED OR FAILED TO MEET THE MINIMUM NACE STANDARD OUTLINED IN

RP0285-95

REFERENCE CELL POTENTIAL @

FINAL VOLTAGE

Inst. Off (R3)END (R1)*

STRUCTURE CONTACT POINT

RECTIFIER ON / or Galvanic (STI-P3) RECTIFIER OFF

CENTER (R2)*

FACILITY INFORMATION

PHONE # :

NAME:

CLIENT INFORMATIONNAME:

ADDRESS:

JOB # :

CONTACT:

STATE:

ADDRESS:

SUMMARY OF TESTTHIS SUMMARY IS NOT COMPLETE WITHOUT THE *SITE SKETCH

RECTIFIER INFO.

TAN

K #

VOLTAGE DECAYEND (R3)*

TYPE OF CERTIFICATION:CERTIFICATION NUMBER:

TIME OF TEST :DATE OF TEST :

END (R1)* END (R2)*

CITY:STATE:FACILITY ID # :

ZIP: CONTACT:CITY: PHONE # :

FAX # :

OUTPUT AMPS:OUTPUT VOLTAGE:

Inst. Off (R1)

Inst. Off (R2)

RECTIFIER ON / or Galvanic RECTIFIER OFF

HR.:

1234

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 RISERFLEX

CONNECTORPIPING RISER (CONTINUOUS, ISOLATED)TANK

No. FILL

RISERTANK

BOTTOMSTP

RISER

FACILITY NAME: FAC. ID # :

CONTINUITY TEST

DATE OF TEST:

Helping our Tank OwnersHelping our Tank Owners

• Second attempt• Developed a CP test form (January 2003)• This Helped!!!• Time intensive• Consistency issues…

– Recognized the need for more comprehensive guidance.

Helping our Tank OwnersHelping our Tank Owners

• Third attempt-Develop a CP Manual– Review existing state publications (chose

Mississippi: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…

CP Manual CP 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 Cell–Moving Ground methods reviewed. 6. CP “Expert” consultation required under certain circumstances –

Example: CP Expert must resolve “inconclusive” test results (no second tester’s opinion)

CP Manual CP 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 galvanic

interruptible systems• 100mV Polarization for interruptible galvanic and impressed current

systems8. Number of Test points:

Galvanic or STI-P3 – 3 test points (one local, one remote, & one optional location) Impressed Current – 3 tests (all local over the structure – no remotes)

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

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

Finalize GuidanceFinalize Guidance

• Draft out to industry for review• Virginia’s CP Manual published May 2006• Weblink address:

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