Laserfiche WebLink
CLEANUP AND ABA ..,..cNT ORDER NO. 92-707 -3- <br /> AMENDING CLEANUP AND ABATEMENT ORDER NO. 91-720 <br /> FOR SOUTHERN PACIFIC TRANSPORTATION COMPANY, <br /> TRACY YARD, SAN JOAQUIN COUNTY <br /> 12. Under Regional Board oversight, several underground tank cleanup cases have <br /> demonstrated the feasibility of excavation and treatment of diesel contaminated soils <br /> to below 50 mg/kg total petroleum hydrocarbons (TPH) as diesel within a single dry <br /> season. <br /> 13. Existing ground water treatment technology, primarily utilizing air stripping and/or <br /> activated carbon, is capable of dependably removing the constituents found in <br /> ground waters at the Tracy Yard to concentrations which are generally non- <br /> detectable by current analytical technology. The commonly achieved detection <br /> levels, by U.S. Environmental Protection Agency (USEPA) analytical methods, are <br /> as follows: <br /> Constituent Detection Level Units Analytical Method <br /> Total petroleum 50 µg/l USEPA Method 8015 <br /> hydrocarbons <br /> Benzene 0.5 µg/I USEPA Method 602 <br /> Toluene 0.5 µg/I USEPA Method 602 <br /> Xylene 0.5 µg/l USEPA Method 602 <br /> Ethylbenzene 0.5 µg/l USEPA Method 602 <br /> Tetraethyl lead 1 <br /> y µg/l USEPA Method 7421 <br /> (as total lead) <br /> 14. For ground water in the Tracy area, the Water Quality Control Plan for the <br /> Sacramento River Basin, Sacramento-San Joaquin Delta Basin, and San Joaquin <br /> River Basin, Second Edition (Basin Plan) identifies the beneficial uses of municipal <br /> and domestic supply, agricultural supply (irrigation and stock watering), and <br /> industrial supply (process and service supply). Ground waters are currently used for <br /> i domestic supply in the vicinity of the Southern Pacific Transportation Company, <br /> Tracy Yard. <br /> 15. The Basin Plan, Chapter ill, Water Quality Objectives, states, in part: <br /> "Ground waters shall not contain chemical constituents in concentrations that <br /> adversely affect beneficial uses. <br /> "Ground waters designated for use as domestic or municipal supply (MUN) shall not <br /> contain concentrations of chemical constituents in excess of the maximum <br />