Laserfiche WebLink
California Regional Water Quality Control Board <br /> Central Valley Region ' <br /> �, <br /> b, <br /> Katherine Hart, Chair `"°���» <br /> Linda S. Adams and G.Brown <br /> 11020 Sun Center Drive#200, Rancho Cordova, California 95670-6114 <br /> Acting Secretary for Governor <br /> Environmental Phone(916)464-3291 •FAX(916)464-4645 *'��. <br /> Protection http://www.waterboards.ca.gov/centralvalley <br /> 1;2011 <br /> 20 January 2011 <br /> Mr. Nathan Crum <br /> Valley Pacific Petroleum Services, Inc. <br /> 166 Frank West Circle <br /> Stockton, CA 95206 <br /> ANNUAL GROUNDWATER MONITORING REPORT AND SOIL VAPOR <br /> EXTRACTION PILOT TEST REPORT, VALLEY PACIFIC PETROLEUM SERVICES, <br /> 930 VICTOR ROAD, LODI, SAN JOAQUIN COUNTY <br /> Regional Water Quality Control Board, Central Valley Region (Central Valley Water <br /> Board) staff reviewed the 5 January 2011 Annual Groundwater Monitoring and <br /> Sampling Report 2010 (Annual Report) and the 29 December 2010 Corrective Action <br /> Plan (CAP) submitted by Ground Zero Analysis, Inc. (GZA) on behalf of Valley Pacific <br /> Petroleum Services, Inc. (Valley Pacific) for the site at 930 Victor Road in Lodi (Site). <br /> Monitoring at the Site is conducted pursuant to Monitoring'and Reporting Program <br /> (MRP) No. R5-2002-0827. <br /> Depths to groundwater were measured on 7 December 2010 in 15 wells, including the <br /> vapor extraction well VEW 1-D. Depth to groundwater ranged from about 56 feet below <br /> ground surface (bgs) to about 59 feet bgs. MW-7, with a total depth of 56 feet bgs, has <br /> been dry since July 2008. Groundwater flowed predominantly to the south at gradients <br /> ranging from about 0.006 feet per foot (ft/ft) to 0.02 ft/ft. The observations and gradient <br /> calculations are consistent with historical observations. <br /> During December, MW-8, MW-9R, and VEW1-D contained 0.26, 0.06 and 0.17 feet of <br /> separate phase hydrocarbons (SPH), respectively. Valley Pacific personnel periodically <br /> remove SPH manually from the wells when observed. The Annual Report estimates that <br /> a grand total of about 1,306 gallons of SPH/water mixture have been removed from Site <br /> wells since April 1994. Maximum concentrations of dissolved constituents of concern <br /> (CDCs) are typically observed in MW-6R. During December, they included <br /> 17,000 micrograms per liter (pg/L) of total petroleum hydrocarbons as gasoline (TPHg), <br /> 1 ,500 pg/L of benzene, 1,000 pg/L of toluene, 580 pg/L of ethylbenzene, 3,500 pg/L of <br /> xylenes, and 3,000 pg/L of methyl tertiary butyl ether (MTBE). These dissolved <br /> concentrations are consistent with the fluctuating contaminant concentrations observed <br /> historically observed in this well. <br /> In the 9 March 2010 Work Plan For Soil Vapor Extraction Pilot Test (Pilot Test Work <br /> Plan), Valley Pacific proposed the May 2010 installation of one triple-nested soil vapor <br /> extraction (SVE) well (VEW1-S, I, D). The SVE pilot test was conducted between 26 <br /> and 29 July 2010 and described in the 11 October 2010 Soil Vapor Extraction Pilot Test <br /> Report (Report). The maximum extraction flow rate in VEW1-I induced vacuums of <br /> California Environmental Protection Agency <br /> Z� Ker.rcled Paper <br />