COMPLIANCE INFO 2002 - 2005 - Laserfiche WebLink

Home Browse Search

r � CRITERIA FOR CATHODIC PROTECTION The testing of the cathodic protection systems were performed in accordance with (Environmental Protection Agency) EPA and NACE International guidelines. The NACE International recommended practice RP-02-85 (latest revision) lists various criteria for cathodic protection of underground metallic tank systems. Listed below is the criterion was used to evaluate the existing cathodic protection systems on UST: A negative (cathodic) voltage of at least 0.85 Volt as measured between the structure surface and a saturated copper/copper sulfate reference electrode contacting the electrolyte. Determination of this voltage is to be made with the protective current applied. Consideration should be given to voltage(IR) drop. RESULTS Data for UST can be found in Table 1 through 3. Each of the UST evaluated is discussed below. Waste Oil Tank: During our initial evaluation on February 18, 2005, it was noted that the waste oil tank Test Board was missing and the wires were severed. Following initial testing it was determined that the black wires are the anode wires and the white wire is a test/drain lead. As-found measurement of the fill tube potential was -0.721V which is below the minimum criterion of -0.850V. The black wires and the white wires were then temporarily connected for testing and the potential at the fill tube shifted from -0.721 V to -0.924V, bringing the potential above the criterion level and providing adequate level of cathodic protection. The wires were extended and a test board installed by City staff. During our follow up evaluation on March 4, 2005, all components were tested and the potentials were measured at -0.972 V (Table 2). These levels are above minimum criterion and the cathodic protection system is functioning properly at this time. Diesel Tank: Potentials measured on the fill tube and test lead were -1.313V and -1.328V,respectively. These values indicate proper level of cathodic protection. All anodes are operating properly except for the anode connected to #3 terminal on the Test Board. That anode appears to be consumed, but is not impacting the levels of cathodic protection at this time. Blackstone 2 Group Ltd.