Laserfiche WebLink
• AK G L,4 /, L2 #e"' <br />Water Boards <br />Central Valley Regional Water Cluallty Control Board <br />18 June 2015 <br />Greg McIver <br />The Source Group, Inc. <br />751 Laurel Street, Suite 722 <br />San Carlos, CA 94070 <br />s Earua Q. 04 44. <br />Rri� raa <br />REMEDIAL ACTION WORK PLAN, FORMER COUNTRYSIDE MARKET, 10848 COPPEROPOLIS <br />ROAD, STOCKTON, SAN JOAQUIN COUNTY, EAR ACCOUNT CASE # R10-129 <br />The California Regional Water Quality Control Board — Central Valley Region (Central Valley Water <br />Board) staff reviewed the Air Sparging Pilot Test Related Activities Report and Remedial Action Work <br />Plan (Work Plan), dated 30 April 2015 prepared by The Source Group, Inc. (TSGI). In the Work Plan, <br />TSGI proposed installation of an air sparging (AS) and soil vapor extraction (SVE) treatment system at <br />the Former Countryside Market in Stockton. <br />In January 2015, TSGI conducted an AS and SVE pilot study that confirmed the technical feasibility of <br />implementing an AS and SVE as an effective remedial option. Four soil borings were advanced and <br />completed as 2" diameter air sparging wells AS -1 and AS -2, observation well OBS -1 and soil vapor <br />extraction well VW -1. AS -1 and AS -2 were screened 110' to 115' below ground surface (bgs). OBS -1 <br />was screened 80' to 120' bgs, and VW -1 was screened 30' to 60' bgs. Depth to groundwater was <br />approximately 99' bgs. <br />Soil samples were collected at 5' intervals for chemical analyses, field screening, and lithology to confirm <br />that the design of the SVE/AS treatment system was appropriate. Soil was analyzed for Total Petroleum <br />Hydrocarbons as Gasoline (TPHg) by United States Environmental Protect Agency (USEPA) Method <br />8015B Modified. Benzene, Toluene, Ethylbenzene, Xylenes, the five (5) fuel -oxygenates Di Iso Propyl <br />Ether (DIPE), Ethylene Tert Butyl Ether (ETBE), Methyl Tert Butyl Ether (MTBE), Tertiary Amyl Methyl <br />Ether (TAME), and Tertiary Butyl Alcohol (TBA), lead scavengers 1, 2-Dichloroethane (1, 2 -DCA) and <br />Ethylene Dibromide (EDB), and Naphthalene by USEPA Method 8260B. Soil results from borings AS -2, <br />VW -1, and OBS -1 (AS -1 was not sampled) are given in milligrams per kilogram (mg/kg) in Table 1: <br />Well <br />TPHg 1Benzene <br />Toluene <br />Eth benzene <br />Xylenes <br />Naphthalene <br />EDB 2 <br />1,2 -DCA <br />AS -2-95' <br /><1.0 <br />0.0031 <br />0.026 <br />0.016 <br />0.09 <br />0.014 <br />0.0026 <br />0.044 <br />VW -1-40' <br />4,500 <br /><5.0 <br />220 <br />130 <br />720 <br />96 <br /><5.0 <br /><5.0 <br />VW -1-60' <br />3,700 <br /><2.0 <br />160 <br />100 <br />570 <br />61 <br /><2.0 <br /><2.0 <br />OBS -1- <br />20' <br />140 <br /><0.10 <br /><0.10 <br />0.1 <br />1.8 <br />6.8 <br /><0.10 <br /><0.10 <br />OBS -1- <br />55' <br />1,600 <br /><0.50 <br />23 <br />26 <br />137 <br />23 <br /><0.50 <br /><0.50 <br />OBS -1- <br />106' <br /><1.0 <br /><0.001 <br />0.0061 <br />0.0026 <br />0.014 <br />0.0032 <br /><0.001 <br /><0.001 <br />KwtL E. Lmm rr acD. P.E-, oww I Peau O. Omavor P.E., BCEE, ®mre omwxm <br />I I CM Dun Car= C+hs ML Randa Caftx . CA OWI I err <br />0 noavuao rwra <br />