Laserfiche WebLink
1 <br /> 1 INTRODUCTION <br />' This submittal presents Aqua Science Engineers, Inc (ASE)'s workplan t o <br /> conduct additional off-site groundwater assessment downgradient of <br />' Frank's One Stop located at 2072 West Yosemite Avenue in Manteca, <br /> California (Figure 1) This workplan was prepared as required by t h e <br /> Cleanup and Abatement Order No R5-2003-0713 (Appendix A) issued by <br />' the California Regional Water Quality Control Board, Central Valley <br /> Region <br />' 2 . 0 BRIEF SITE HISTORY AND BACKGROUND INFORMATION <br />' The site is currently a gasoline and diesel service station with additional <br /> on-site businesses such as automotive repair, bait shop, mini market and <br /> U-Haul truck rental <br /> 2 - 1 Februai:y 1995 Site A-ssessment <br />' In February 1995, Geological Audit Services of Stockton, California drilled <br /> 13 soil borings (GB-1 through GB-10, ISLAND 1, IS and IW) at the site <br /> (Figure 2) Up to 1,400 parts per million (ppm) total petroleum <br /> hydrocarbons as gasoline (TPH-G), 18,000 ppm total petroleum <br /> hydrocarbons as diesel (TPH-D), 25 ppm benzene, 44 ppm toluene, 2 4 <br />' ppm ethyl benzene and 83 ppm total xylenes were detected in soil <br /> samples collected from the site Up to 13,000 parts per billion (ppb) <br /> TPH-G, 2,500 ppb TPH-D, 83 ppb benzene, 840 ppb toluene, 230 ppb ethyl <br />' benzene and 1,900 ppb total xylenes were detected in groundwater <br /> samples collected from the borings The highest concentrations were <br /> detected in samples collected northwest or adjacent to the underground <br /> storage tanks (USTs), and in samples collected adjacent to the diesel fuel <br /> dispenser <br /> 2 . 2 A1)ril. 1997 Site Assessmen <br /> In April 1997, Remedy, Inc of Fremont, California, drilled ten soil borings <br /> (B-1 through B-10) at the site (Figure 2) Soil samples were collected at <br /> 12-feet below ground surface (bgs) in each of the borings Up to 880 <br /> ppm TPH-G, 1 0 ppm TPH-D, 0 89 ppm benzene, 15 ppm toluene, 10 p p m <br /> ethyl benzene, 63 ppm toluene and 92 ppm methyl tertiary butyl ether <br /> (MTBE) were detected in the soil samples collected from these borings <br /> Groundwater samples collected from these borings contained up to <br /> 130,000 ppb TPH-G, 760 ppb TPH-D, 5,300 ppb benzene, 28,000 p p b <br /> toluene, 3,500 ppb ethyl benzene, 21,000 ppb total xylenes and 21 ,000 <br /> Frank's One Stop Workplan — September 2003 <br />