Laserfiche WebLink
corrpro� HAYWARD OFFICE <br /> 20991 Cabot Blvd, Hayward,CA 94545 <br /> anAEGIONcampany 510.614.88001 www.corrpro.com <br /> NACE International Standard Practice SP0169-2013 — "Control of External <br /> Corrosion on Underground or Submerged Metallic Piping Systems" <br /> o -65OmV Criterion: A negative polarized potential of at least negative 850 mV <br /> relative to a saturated copper.-copper sulfate reference electrode. <br /> 0 100mV Criterion: A minimum of 100 mV of cathodic polarization between the <br /> structure surface and a stable reference electrode contacting the electrolyte. The <br /> formation or decay of polarization can be measured to satisfy this criterion. <br /> • Electrical Continuity-- Verifying electrical continuity was done by connecting a lead between <br /> the structure connection located at the anode junction box and the negative terminal of the <br /> voltmeter. The positive connection necessary to complete the measuring circuit was made <br /> by directly contacting the structure under test. The potential between the structure <br /> connection and the structure where it was accessible above ground was measured. If the <br /> potential difference between the structure connection and the structure was less than 3 mV, <br /> the structure was determined to be electrically continuous to the structure connection. <br /> Results and Analysis <br /> The structure-to-soil potentials recorded during this survey demonstrated compliance with <br /> applicable NACE cathodic protection criteria for buried steel storage tanks. The Code of <br /> Federal Regulations (CFR - Rule 40 CFR, Subpart C, Section 280.31) additionally requires <br /> vehicle refueling facilities be surveyed within six months of any underground storage tank <br /> system modifications and at least once every three years. <br /> The structure connection, two tanks, and vent piping were determined to be electrically <br /> continuous with each other. <br /> Recommendations <br /> • Retain a qualified Corrosion Engineer to perform a cathodic protection survey within three <br /> years or within six months of any system modifications. <br /> Corrpro appreciates the opportunity to provide cathodic protection services. Should you have <br /> any questions, comments or require additional information, please do not hesitate to contact me <br /> directly at(510) 614-8800 x 570229. <br /> RECEIVEE <br /> MAY 0 7 2015 <br /> [ENVIRONMENTAL <br /> I IC,,T,J nl—r�n rvrn}r-q iT <br /> Project No. 340571048 Page 2 of 5 <br />