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TABLt"1 - CHECKLIST OF REQUIRED DAMA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and Location: Newark Sierra Paperboard, 800 West Church Street, Stockton, San Joaquin County
<br /> 1. Distance to production wells for municipal, domestic, agriculture, Four active water supply wells are within 800 feet of
<br /> industry and other uses within 2000 feet of the site; the former USTs. The nearest water supply well is
<br /> approximately 50 feet south of the southeast UST.
<br /> 2. Site maps, to scale, of area impacted showing locations of former and existing tank systems, Three USTs were closed in
<br /> Y
<br /> excavation contours and sample locations, boring and monitoring well elevation contours, place from 1994 to 1998.Site maps provided.
<br /> gradients, and nearby surface waters, buildings, streets, and subsurface utilities;
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<br /> 3. Figures depicting lithology(cross section), treatment system diagrams; Boring logs and cross-sections show
<br /> predominantly silt and clay.
<br /> 4. Stockpiled soil remaining on-site or off-site disposal(quantity); Approximately 713 tons of excavated soil were
<br /> p g p (q y)' disposed at Altamont Landfill.
<br /> 5. Monitoring wells remaining on-site, fate; Four monitoring wells currently exist on-site. The wells will be properly
<br /> Y destroyed pending site closure.
<br /> �Y 6. Tabulated results of all groundwater elevations and depths to water, Groundwater-levels vary from 9 to 26 feet below
<br /> ground surface, and flow has varied during the
<br /> previous sampling events.
<br /> 0 7. Tabulated results of all sampling and analyses: Maximum groundwater monitoring results near the former 210,000-
<br /> gallon UST show TPHd at 1.1 mg/1 in 6/93, and<0.5 from 8/93 to 6/99.
<br /> Detection limits for confirmation sampling All other constituents are non-detect. Maximum soil results in mg/kg
<br /> IV❑Lead analyses show TPHd at 8100, TPHmo at 9600, benzene at 0.022, toluene at 0.010,
<br /> ethyl benzene at 0.054,xylenes at 0.14, and MtBE at<0.05(by 8020).
<br /> y� 8. Concentration contours of contaminants found and those remaining in soil Lateral and vertical extent of soil and
<br /> and groundwater, and both on-site and off-site: groundwater contamination is defined.
<br /> © Lateral and 171 Vertical extent of soil contamination
<br /> 71 Lateral and 0 Vertical extent of groundwater contamination
<br /> N 9. Zone of influence calculated and assumptions used for subsurface A remediation system was not operated at
<br /> remediation system and the zone of capture attained for the soil and this site.
<br /> groundwater remediation system;
<br /> T1 10.Reports/information Unauthorized Release Form 0 QMRs
<br /> Boring logs FNPARFRP Other(Add. Closure Information, 9/99& 10/00)
<br /> 11.Best Available Technology(BAT) used or an explanation for not using BAT; Remove USTs, and contaminated soils,
<br /> natural attenuation.
<br /> 12.Reasons why background was/is
<br /> unattainable using BAT, TPHd and heavy chain fuel oil remains in shallow on-site soils.
<br /> 13.Mass balance calculation of substance The consultant estimated that 68 gallons of fuel oil remain in shallow soils
<br /> Y❑ treated versus that remaining; near the two former 5,000-gallon USTs,and 10 gallons of diesel remain in
<br /> shallow soils near the former 210,000-gallon UST.
<br /> 0 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 Remaining contamination is limited to shallow on-site
<br /> Mimpact water quality, health, or other beneficial uses;and soils. Contamination will naturally attenuate.
<br /> By: Comments: Two 5,000-gallon No. 6 fuel oil USTs were closed in place in May 1994, and one 210,000-gallon No. 6 fuel oil
<br /> .` UST was removed in July 1998. Soil contamination was identified below the two 5,000-gallon USTs, and soil was
<br /> excavated and disposed at Altamont landfill. The consultant estimates that 68 gallons of fuel oil remain in site soils near
<br /> the former 5,000-gallon USTs. Soil contamination was also identified around the rim of the former 210,000-gallon UST,
<br /> Date: and soil was excavated and disposed at Altamont landfill. The consultant estimates that 10 gallons of fuel oil remain in
<br /> / site soils near the former 210,000-gallon UST. Monitoring wells around the former 210,000-gallon UST have been non-
<br /> '%1..1co detect for all constituents since 8/93. Based on the limited mobility of the fuel oil in soil and groundwater, and the limited
<br /> extent of site contamination, Board staff concur with San Joaquin County's closure recommendation.
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