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<br /> (ABLE 1 -CHECKLIST OF REQUIRED DATA
<br /> I FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
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<br /> Site Name and Location: Fremont Shell Station,2494 East Fremont Street,Stockton,San Joaquin County
<br /> Y 1- ❑istarace to production wells form�tnicipal, domestic, In 2001,a sensitive receptor survey was conducted.Four water
<br /> supply wells were identified within a 2,000-foot radius of the site.
<br /> agriculture, industry and other uses within 2040 feet of the site; The closest well is a domestic well about 600 feet east-southeast
<br /> Y of the site.A water sample was collected from this well in 2009
<br /> that confirmed no impact to this well,
<br /> 2. Site maps, to scale,of area impacted showing locations of farmer Two 5,000-gallon, two 8,000-gallon tanks were removed
<br /> tanks stems,excavation contours and sample locations, rn 1996. Two gasoline and one waste oil tank,
<br /> and existing y p dispensers,and product piping were removed in 2005.
<br /> Y borings and monitoring wells elevation contours, gradients, and nearby Site maps showing the location of former and current
<br /> surface waters, buildings, sheets,and subsurface utilities; tanks,buildings and streets were provided in reports.
<br /> 3.Figures depicting lithvlogy(cross Coarse-grained sediments occur at varying thicknesses at three depth intervals;10 to
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<br /> section),treatments stem diagrams; 30 d-'bgsj 70 to 85 ft.bgs and 105 to 115 ft.bgs. Borings and cross-sections provided
<br /> y g in reports.No treatment was conducted.
<br /> y 4. Stockpiled soil remaining on-site or 143 tans of soil and pea gravel were disposed at the Allied Waste Industries Forward
<br /> landfill in Manteca in 2005. San Joaquin Co. will confirm waste from well destruction is
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<br /> off-site disposal(quantity); removedbefore final closure.
<br /> f Ten groundwater monitoring wells,six shallow and four deeper-zone wall on-site. Wells
<br /> 5.Monitoring wells remaining on-site, fate; will be properly destroyed under ermit from San Joa uln Co.prior to closure,
<br /> Y 6. Tabulated results of all groundwater Depth to 9.w.ranged from 41 to 57 ft.bgs,Groundwater gradient in,both the shallow
<br /> ! elevations and depths to water; and deeper zones predominantly scuth•soutbeast
<br /> i v 7. Tabulated results of all sampling and analyses:
<br /> Tabulated results are presented in the Closure Request Report.
<br /> ❑Detection limits for confirmation sampling
<br /> Lead analyses
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<br /> Y 8. Concentration contours of contaminants found and those remaining in sail
<br /> and groundwater,and both on-site and off-site:
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<br /> Y Lateral and Y Vertical extent of soil contamination Contaminant contours presented in Closure
<br /> ❑Lateral and ❑Vertical extent of groundwater contamination Request Report for soil and groundwater.
<br /> Y Y
<br /> N 9-Zone of influence calculated and assumptions used for subsurface No cleanup actions were conducted at this Site.
<br /> remediation system and the zone of capture attained for the soil and
<br /> groundwater remediation system;
<br /> Y 10.Reports/information ❑Y Unauthorized Release Form ❑Y QMRs
<br /> Well and boring logs PAR ❑FRP ❑Other
<br /> Y 11.Best Available Technology(BAT)used or an Excavation of 103 tons of soil andpea gravel along with WNA effectively removed
<br /> explanation for not using BAT,, secondary source from the site
<br /> Y 12.Reasons why background waslis unattainable Contaminant concentrations are decreasing,the areal extent of the pollution is
<br /> shrinking and background is predicted to be achieved through natural
<br /> using BA T,' de radation.
<br /> Y 13.Mass balance calculation of substance About 833 lbs.(935 gallons)of total petroleum hydrocarbons were calculated to
<br /> Treated versus that remaining; be remaining in soil and 9.5lbs.(1.5 gallons)remain in groundwater
<br /> 14.Assurnptions,parameters, calculations and model used Mass of pollutants calculated on an estimated average
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<br /> in rislr assessments, and fate and transport modeling; concentration of pollutants concentration to a specific volume
<br /> of impacted soil
<br /> 15.Rationale why conditions remaining at site will not Contaminant concentrations are decreasing,the areal extent of the
<br /> Y-1 adversely impact water quality health, or other beneficial pollution is shrinking and background is predicted to be achieved
<br /> through natural degradation.
<br /> uses;and
<br /> N 16,WET or TCLP results NR
<br /> BY., Commenfst The site is an operating Shell-branded service station in a mixed commercial and residential area. An
<br /> up-gradient Arco service station is an open UST case.Two 5,000-gallon,two 8,000-gallon tanl[s were removed in
<br /> cic 1996. Two gasoline and ane waste oil tank,dispensers,and product piping were removed in 2045. Benzene and 1,2-
<br /> DCA were the predominant contaminants of concern at this Site. Horizontal and vertical defineation indicated the
<br /> hydrocarbon impacts were confined to the Shell property. Vertical impacts extended to about 150 feet below ground
<br /> Date-. surface. Concentrations are naturally decreasing and the areal extent of impacts are shrinking. No prediction when
<br /> 912512014 water quality will be restored was provided.
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