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Linda S. Adams
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<br />California Regional Water duality Control Board
<br />Central Vallee Region
<br />Karl E. Longle.N. ScD, N.E., (:hair
<br />Sacramento Office
<br />1 1020 Sun Ccnter Drk c #200. Rancho Cordova. Cahl'oTma 95,67(�61 1-4
<br />Phone (916)404-32()l - 1 AX (916)404-4645
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<br />Jim Munch, P.E. FROM: Jim Barton, P.G.
<br />Senior Engineer Engineering Geologist
<br />UST Enforcement Unit UST Enforcement Unit II
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<br />DATE: 12 May 2009 SIGNATURE: �” _ A �", s -.
<br />SUBJECT: REVIEW; CLOSURE REPORT, FORMER CHEVRON STATION 9-5775,
<br />301 WEST KETTLEMAN LANE, LODI, SAN JOAQUIN COUNTY,
<br />(LUSTIS I.D. #391019)
<br />Site Background:
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<br />The subject site (Site) is a former Chevron Gasoline Station, which currently operates as a car
<br />wash and an auto lubricant center (Figures 1 and 2). The former underground storage tank
<br />(UST) system included three dispenser islands, three 10, 000 -gallon gasoline USTs, one
<br />1,000 -gallon and one 550 -gallon used oil UST's, and one hydraulic hoist.
<br />In August 1998, the five former USTs, the hydraulic hoist, the three dispenser islands.
<br />associated product piping, and the station building were removed from the Site. Subsequently
<br />the property was sold and the current car wash and auto lubrication buildings were
<br />constructed. Analytical results of confirmation soil samples collected at 14.5 feet below
<br />ground surface (ft. bgs) beneath the eastern end of the middle gasoline UST reported
<br />maximum petroleum hydrocarbon contaminant concentrations as Total Petroleum
<br />Hydrocarbons as gasoline (TPHg), 14,000 milligrams per kilogram (mg/kg); benzene.
<br />84 mg/kg; toluene, 1500 mg/kg; and methyl tert-butyl ether (MtBE), 56 mg/kg.
<br />Subsequently, the soil beneath the eastern end of the middle gasoline UST was over
<br />excavated in August 1998 to 22.5 ft. bgs. Maximum confirmation soil sample results were
<br />TPHg, 2,300 mg/kg. benzene. 4.1 mg/kg, and MtBE, 330 mg/kg.
<br />In January 1999, one soil boring (SB -1) was advanced and four monitoring wells were installed
<br />(MV\/ -1 through MW -4) at the Site. Maximum soil sample concentration for SB -1 were TPH-g,
<br />1,200 mg/kg; benzene, 0.81 mg/kg; toluene, 4.0 mg/kg; xylenes, 200 mg/kg; MtBE, 110 mg/ka.,
<br />and ethyl tertiary butyl ether (EtBE), 1.3 mg/kg. Maximum groundwater concentrations were
<br />TPH-g, 1.100 micrograms per Liter (ug/L); benzene. 6,800 ug/L; toluene, 810 ug/L; xylenes.
<br />780 ug/L, MtBE, 62,000 ug/L; and EtBE, 2,400 ug/L. In February 2000. two additional soil
<br />borings (SB -2 and SB -3) were advanced-, and five additional monitoring wells (MW -5A. MW -6.
<br />MW -7A, MW -8A, and MW -9A), four soil vapor extraction wells (VE -1 through VE -4), and one
<br />groundwater extraction well (EX -1), were installed. Maximum soil sample concentrations were
<br />California Environmental Protection Agency
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