Cathodic Protection Guidance? Who needs that? Aren t t NACE & STI enough? David Robinett Virginia Dept. of Environmental Quality

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1 Cathodic Protection Guidance? Who needs that? Aren t t NACE & STI enough? David Robinett Virginia Dept. of Environmental Quality

2 December 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

3 December 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:

4 volts

5 6.2 Volts 4.5 Volts

6 8.7 MA 8.6 MA 9.1 MA 8.9 MA

7 8.7 mv 8.6 mv 9.1 mv 8.9 mv

8 Help 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

9 Helping 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!!!

10 JOB # : PIPING # STRUCTURE CONTACT POINT STRUCTURE CONTACT POINT SIGNATURE OF PERSON CONDUCTING TEST CATHODIC PROTECTION TEST FORM SUMMARY OF TEST THIS SUMMARY IS NOT COMPLETE WITHOUT THE *SITE SKETCH HR.: OUTPUT VOLTAGE: OUTPUT AMPS: REFERENCE CELL RECTIFIER ON / or Galvanic (STI-P3) END (R1)* FACILITY INFORMATION DATE OF TEST : NAME: ADDRESS: CITY: PHONE # : STATE: ZIP: CONTACT: LAT: FACILITY ID # : LONG: CLIENT INFORMATION NAME: ADDRESS: CITY: PHONE # : STATE: ZIP: CONTACT: FAX # : TANK # RECTIFIER INFO. CENTER (R2)* END (R3)* Inst. Off (R1) RECTIFIER OFF Inst. Off Inst. Off (R2) (R3) REFERENCE CELL RECTIFIER ON / or Galvanic RECTIFIER OFF Inst. Off Inst. Off FINAL END (R1)* END (R2)* (R1) (R2) VOLTAGE FINAL VOLTAGE VOLTAGE DECAY TESTER NAME: SOURCE OF CERTIFICATION: TYPE OF CERTIFICATION: CERTIFICATION NUMBER: TIME OF TEST : VOLTAGE DECAY STRUCTURE PASSED OR FAILED TO MEET THE MINIMUM NACE STANDARD OUTLINED IN RP STRUCTURE PASSED OR FAILED TO MEET THE MINIMUM NACE STANDARD OUTLINED IN RP

11 DATE OF TEST: FACILITY NAME: FAC. ID # : TANK No FILL RISER TANK BOTTOM STP RISER VENT RISER CONTINUITY TEST FLEX PIPING CONNECTOR RISER (CONTINUOUS, ISOLATED) 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

12 Helping 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.

13 Helping 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

14 CP Manual points-of-clarity 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 RP IR (voltage) drops considered and instant-off tests required for all impressed current systems 5. 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)

15 CP Manual points-of-clarity continued 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 systems 8. 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

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23 Finalize Guidance Draft out to industry for review Virginia s CP Manual published May 2006 Weblink address: