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<br /> TAB 1 - CHECKLIST OF REQUIRED TA
<br /> FOR NO .FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and Location: Alliance Gas Station, 8750 South EI Dorado Street, French Camp, San Joaquin County
<br /> Groundwater contamination was not identified,and a
<br /> 1. Distance to production wells for municipal, domestic, agriculture, well receptor survey was not required. As shown in
<br /> industry and other uses within 2000 feet of the site; GeoTracker,no wells are located within 2,000 feet
<br /> i' Five USTs were removed
<br /> 2. Site maps, to scale, of area impacted showing locations of former and existing tank systems, in 8/89. Site maps are
<br /> excavation contours and sample locations, boring and monitoring well elevation contours, provided in the PIER_
<br /> gradients, and nearby surface waters, buildings, streets, and subsurface utilities;
<br /> Lithology consists of silt and clay to 24 feet,and
<br /> 3. Figures depicting lithology(cross section), treatment system diagrams; silty sand to 30 feet, the total depth investigated.
<br /> 4. Stockpiled soil disposed off-site(quantity); The disposition of excavated soil was not presented. The soils were
<br /> likely returned to the tank pit excavation's.
<br /> S. Monitoring wells remaining on-site, fate; Groundwater contamination was not identified, and monitoring wells were not
<br /> FN 5.
<br /> First groundwater was encountered at 30 feet. The
<br /> 6. Tabulated results of all groundwater elevations and depths to water estimated flow direction is to the northeast
<br /> 7.Tabulated results of all sampling and analyses: Soil samples collected during the USTremoval in 8/89 showed total
<br /> petroleum hydrocarbons at 76 mg/kg, toluene at 0.005 mg/kg,and lead
<br /> Detection limits for confirmation sampling at 11 mg/kg. The results of soil and groundwater samples collected
<br /> F]
<br /> ❑Lead analyses from three borings in 3102 were non-detect for all constituents
<br /> including MtBE at acceptable detection limits.
<br /> 8. Concentration contours of contaminants found and those remaining in soil Soil samples collected at 5 to 30 feet using
<br /> ❑ and groundwater, both on-site and off-site: push probe methods were non-detect for
<br /> ❑ Latera!and 0 Vertical extent of soil contamination all constituents. Three groundwater grab
<br /> samples collected the three soil borings
<br /> Y Lateral and Vertical extent of groundwater contamination were also non-detect for all constituents.
<br /> 9. Zone of influence calculated and assumptions used for subsurface
<br /> Based on minor soil contamination at the
<br /> 0 remediation system and the zone of capture attained for the.:soil and former UST areas,site remediation was not
<br /> groundwater remediation system; required.
<br /> y❑ 10.Reports/information Y❑ Unauthorized Release Form ❑ QMRs
<br /> Y❑ Boring logs N❑ PAR N❑ FRP ❑ Preliminary Investigation and Evaluation Report 4/02.
<br /> 11.Best Available Technology(BAT) used or an explanation for not using BAT, The USTs were removed.
<br /> Minor contamination remains in soil at the former UST areas. The remaining
<br /> 12.Reasons why background,wasrs.,e._, j �_ =.—�- ,t- -�_. =_ -
<br /> ❑Y contamination does not present a significant threat to groundwater.
<br /> unattainable using BAT; I
<br /> ubstance Based on the limited soil contamination identified at the former UST areas,a
<br /> N❑ 13.Mass balance calculation of s
<br /> treated versus that remaining; mass balance.was not required.
<br /> i
<br /> 14. Assumptions,parameters, calculations and model used in risk Based% on the limited soil contamination identified at the
<br /> assessments, and fate and transport modeling; former UST areas,a risk assessment was not required.
<br /> ❑
<br /> 15. Rationale why conditions remaining at site will not adversely Minor,contamination remains in soil at the former UST
<br /> impact water quality, health, or other beneficial uses. areas. The remaining contamination does not present a
<br /> significant threat to groundwater.
<br /> N
<br /> By: Comments: The site is a former gas station that reportedly operated from 1963 to 1985. In August 1989, one 250-gallon
<br /> MH waste oil;one 3,000-gallon gasoline, one 10,000-gallon diesel, and two 5,000-gallon gasoline and diesel USTs were
<br /> removed from the subject site. Tank pit soil samples showed TEPH at 19 to 76 mg/kg;'toluene at 0.0015 to 0.005 mg/kg,
<br /> and lead at 8 to 11 mg/kg. In March 2002, three borings were completed to 30 feet and soil and groundwater samples
<br /> Date: were collected and analyzed for TPHg, BTEX, and fuel oxygenates including MtBE. All samples were non-detect for all
<br /> 5/20102 constituents at acceptable reporting limits. Based on the site characterization completed to date, Board staff concur with
<br /> San Joaquin County's closure recommendation.
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