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TABL�7?- CHECKLIST OF REQUIRED DATA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
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<br /> Site Name and Location: The Record, 530 Market Street,Stockton, San Joagruin County
<br /> 0 1. Distance to production wells for municipal, domestic, agriculture, Site is located in downtown Stockton with no public
<br /> industry and other uses within 2000 feet of the site; wells within 2000 feet.
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<br /> 2, Site maps, to scale, of area impacted showing locations of former and existing tank One 10,000-gallon unleaded
<br /> systems, excavation contours and sample locations, boring and monitoring well s gasoline tank was removed in
<br /> elevation contours, gradients, and nearby surface waters, buildings, streets, and: January 2003.
<br /> subsurface utilities,
<br /> 0 3. Figures depicting lithology(cross section), treatment system diagrams; Site lithology consists of clay, slit clay and silty
<br /> sand to 36 feet, the total depth investigated.
<br /> 4. Stockpiled soil disposed off-site(quantity); approximately 275 cubic yards of excavated soil were tested and
<br /> replaced back into the exca'vation.' Excavated soil results were xylenes,
<br /> �� 0.0.078 mg/kg and MtBE, 0.0,12 mg/kg.
<br /> I ' 1 5. Monitoring wells remaining on-site fate;
<br /> YI 6. Tabulated results of all groundwater elevations and depths to water; The depth to wafer was 34 feet and the regional
<br /> groundwater flow direction is to the north.
<br /> 7. Tabulated results of all sampling and analyses: soil samples collected at the time of the tank removal reported
<br /> y xylenes, 0.029 mg/kg;MtB.E, 0.322 mg/kg; TBA, 4.58 mg/kg;and TAME,
<br /> Detection limits for confirmation sampling 0.027 mg/kg. Soil samples collected at 15, 20, and 30 feet were all non-
<br /> Lead analyses detect for gasoline constituents, Groundwater grab sample results
<br /> were non-detect for TPHg 18TEX,and fuel oxygenates.
<br /> 8. Concentration contours of contaminants found and those remaining in soil
<br /> and groundwater, both on-site and off-site; The tank excavation soil samples and on-
<br /> Lateral and Vertical extent of soil contamination site soil boring define the extent of
<br /> Lateral and Vertical extent of groundwater contamination contamination.
<br /> Q9.Zone of influence calculated and assumptions used for subsurface Based on the limited extent of soil
<br /> remediation system and the zone of capture attained for the soil and contamination, an engineered remediation
<br /> groundwater remediation system;.. system was not required at this site.
<br /> Q10-Reports/information Unauthorized Release Form QMRs
<br /> Y❑ Boring logs PAR,.' ❑ FRP Other .�
<br /> 11.Best Available Technology(BAT) used or an explanation for not using BAT,' Remove USTs and natural attenuation.
<br /> 12.Reasons why background was/is s
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<br /> --"-unattainable usin BAT-, Minor soil contamination remains on-site.
<br /> 13.Mass balance calculation of substance
<br /> treated versus that remaining; Mass balance was not calculated for soil or groundwater.
<br /> 14.Assumptions,parameters, calculations and model used in risk
<br /> assessments, and fate and transport modeling,and A risk assessment was not required.
<br /> 0 15. Rationale why conditions remaining at site.will not adversely Soil contamination is limited in extent, and
<br /> impact water quality, health, or other beneficial uses. contamination is not expected to reach groundwater.
<br /> The groundwater sample shows no impact from soil
<br /> contamination. '
<br /> By: Comments: One 10,000-gallon unleaded gasoline UST was removed front the subject site in 1103. Minor soil
<br /> JLB contamination was identified at the UST area. Excavated soil was mixed with clean soil and reused in the LIST pit. One
<br /> boring and one grab groundwater sample were completed to delineate contamination at this site. No contamination was
<br /> Date: identified in soils at 15, 20, or 30 feet bgs, or in groundwater. Based on the minor soil contamination and lack of
<br /> contamination in groundwater, Regional Board staff concur with San Joaquin County's Closure Recommendation.
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<br /> 4/30/03
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