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TABLE I -CHECKLIST OF REQUIRED DATA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and Location: Spreckels Sugar Co., Inc.(Former Holly Sugar), 20500 Holly br_, Tracy, San Joaquin County
<br /> (RB#390132)
<br /> _Y1 1. Distance to production wells for municipal, domestic, Three inactive process supply wells are located 400'to
<br /> agriculture,industry and other uses within 2000 feet of the site. the southwest 550'to the west, and 800'to the north. The 1
<br /> facility is closed and the wells were not impacted or t
<br /> threatened.
<br /> Y 2. Site maps, to scale, of area impacted showing locations of Two 1,000-gallon gasoline USTs were removed 10185
<br /> any former and existing tank systems, excavation contours and (Sites A and B), and one 10,000-gallon fuel oil k
<br /> sample locations, boring and monitoring well elevation underground bunker UST was removed 1/11 during site r
<br /> contours, gradients, and nearby surface waters, buildings, demolition.
<br /> streets, and subsurface utilities; .
<br /> :YD 3. Figures depicting lithology(cross section), treatment system Site lithology consists of clay to 17', the total depth of the I
<br /> diagrams; investigation. The nearby City wastewater treatment fk
<br /> ponds (WWTP)investigated to 100'bgs and reported
<br /> clay,silt sand, and gravel.
<br /> Y 4. Stockpiled sail remaining on-site or off-site disposal (quantity}; 1 700 y of over-excavated soil was transported to
<br /> Forward Landfill in Manteca
<br /> 5. Monitoring wells remaining on-site, fate; Two remaining monitoring wells(MW-A1 and MW-BIR)installed for the USTs
<br /> investigation will be properly abandoned. The City WWTP monitoring wells,
<br /> also used for the USTs investigation, remain for WDRs monitoring.
<br /> 6. Tabulated results of all groundwater Depth to groundwater varied from 4'to 10'bgs. Groundwater flow
<br /> elevations and depths!a water, direction was towards the northeast
<br /> LyJ 7. Tabulated results of all sampling All data adequately tabularixed in various reports, including closure report.
<br /> and analyses:
<br /> E .Detection limits for confirmation
<br /> sampling
<br /> 10 Lead analyses
<br /> 8. Concentration contours of contaminants found and those remaining in soil and The extent of the identified
<br /> groundwater,and both on-site and off-site: contamination is described in the
<br /> reports.
<br /> ElLateral and Vertical extent of soil contamination
<br /> FYI Lateral and FYI Vertical extent of groundwater contamination
<br /> 9. Zone of influence calculated and assumptions used for subsurface remediation An engineered remediation was not 1
<br /> system and the zone of capture attained for the soil and groundwater remediation required by the lead agency.
<br /> system;
<br /> 10.Reports I information 51 Unauthorized Release Form FYI QMRs 9198 to 6109
<br /> FY] Well and boring logs Fy-1 PAR FRP ❑Y Other Closure Report(12194)
<br /> LYJ 11.Best Available Technology(BAT)used or an explanation for not using USTs removal,soil over-excavation and
<br /> BAT; natural attenuation.
<br /> �r 12. Reasons why background wasrs. Minor residual soil and groundwater(MW-B 1)contamination remain on- i
<br /> ttainable using BAT; site.
<br /> N: 13.Mass balance calculation of substance Mass was not calculated by the consultant.
<br /> treated versus that remaining,'
<br /> Y14. Assumptions,parameters, calculations RP's consultant(Ground Zero)states that based on soil and GW sampling
<br /> and model used in risk assessments, and fate minimal threat by contact.or vapor migration exists from residual impacts. J!
<br /> and transport modeling; WQGs TPH will be reached in 30 years.
<br /> Y15. Rationale why conditions remaining at site Soil contamination reportedly is limited in extent. Water quality is
<br /> will not adversely impact water quality, health, seriously degraded due to WWTP salinity. All buildings have been
<br /> or other beneficial uses;and demolished and the site is vacant land next to a wastewater treatment
<br /> plant under WDRs.Land use(commercial)is not expected to change in
<br /> the foreseeable future. r
<br /> By: JLB ;;; Comments Two 1,000-gallon gasoline LISTS were removed 10185, and one 10,000-gallon fuel oil UST was
<br /> removed 1/11 during site demolition of the subject site.Minor residual soil and groundwater contamination
<br /> Date: remains on-site. Based upon 17 monitoring events showing declining gasoline concentrations, the limited
<br /> 7/11/2011 extent of contamination reported in soil,groundwater reaching WQGs in 30 years, no foreseeable changes in
<br /> land use,and minimal risks from soil,soil vapor,and groundwater, Regional Board staff concur with.San f
<br /> Joaquin County's Closure Recommendation.
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