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<br /> • TABS 1 - CHECKLIST OF REQUIRED L,,. A
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and Location: Eggiman's Hydraulic, 1112 Harding Way, Stockton, San Joaquin County
<br /> FTI 1. Distance to production wells for municipal, domestic, agriculture, Fourteen wells were located within 2,000 feet of the
<br /> industry and other uses within 2000 feet of the site; site. The nearest well,a water supply well,is located
<br /> approximately 800 feet west of the site.
<br /> 2. Site maps, to scale, of area impacted showing locations of former and existing tank systems,
<br /> excavation contours and sample locations, boring and monitoring well elevation contours,
<br /> gradients, and nearby surface waters, buildings, streets, and subsurface utilities,
<br /> a
<br /> Y 3. Figures depicting lithology(cross section), treatment system diagrams, Soil boring logs show predominantly silt soils
<br /> and silty sand backfill. No treatment system.
<br /> 4. Stockpiled soil remaining on-site or off-site disposal(quantity); Two 1,000-gallon tanks were removed in 1987,and the
<br /> p g p excavation was backfilled.
<br /> 5. Monitoring wells remaining on-site, fate, Monitoring wells were not installed.
<br /> FN 6. Tabulated results of all groundwater elevations and depths to water, The minimum depth to water is estimated at 55 feet
<br /> bgs. Monitoring wells were not installed.
<br /> 7.Tabulated results of sampling and analyses: Maximum soil results for July 1997 soil borings in mg/kg show TPHg at
<br /> 9,100;TPHd at 1,700;Lead at 14;BTEX at 0.90, 91, 190,and 800,
<br /> ©Detection limits for confirmation sampling respectively. MtBE was nondetect at detection limits ranging from 0.01
<br /> Lead analyses to 10 mg/kg.
<br /> 8. Concentration contours of contaminants found and those remaining in soil Lateral extent of soil defined on north,
<br /> and groundwater, and both on-site and off-site: south,and west sides of former UST.
<br /> Lateral andY❑ Vertical extent of soil contamination Vertical extent of soil defined to 30 feet
<br /> Lateral and Vertical extent of groundwater contamination bgs. Groundwater samples were not
<br /> N collected.
<br /> 0 9.Zone of influence calculated and assumptions used for subsurface A remediation system was not installed at
<br /> remediation system and the zone of capture attained for the soil and this site.
<br /> groi*dwater remediation system;
<br /> 10.Reports/information 171 Unauthorized Release Form QMRs
<br /> 19 Boring logs 0 PAR F FRP Y❑ Other(Closure Request, 10/99)
<br /> 0 11.Best Available Technology(BAT)used or an explanation for not using BA T,- No remedial activities were completed.
<br /> 12.Reasons why background waslis
<br /> NA unattainable using BAT,
<br /> 13.Mass balance calculation of substance
<br /> FEtreated versus that remaining,
<br /> 14.Assumptions,parameters, calculations and model used in risk A risk assessment was not completed.
<br /> assessments, and fate and transport modeling;
<br /> 15. Rationale why conditions remaining at site will not adversely The highest concentrations of TPHg and BTEX are
<br /> Eflimpact water quality, health, or other beneficial uses;and present between 10 and 15 feet bgs. Soil contamination
<br /> is limited to the immediate vicinity of the former UST.
<br /> By: Comments: Two USTs were removed in April 1987, and six soil borings were completed in July 1997. TPHg, TPHd, and
<br /> BTEX constituents were identified from soil samples. Groundwater was not encountered at a total depth of 31 feet bgs,
<br /> and groundwater was not collected at this site. Soil contamination has been defined to the immediate area surrounding
<br /> the former USTs. The nearest water supply well is located approximately 800 feet west of the site. Based on the
<br /> Date: concentrations of TPH in soils, and the lack of groundwater data, San Joaquin County's closure recommendation is not
<br /> oP appropriate at this time. For concurrence, Eggiman's Hydraulic must collect a groundwater sample and analyze the
<br /> sample for TPH, BTEX, and fuel oxygenates.
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