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<br /> TAB 1 - CHECKLIST OF REQUIRED 64A
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and Location: Pacific Pride Ripon Card Lock, 816 Hwy 99, Ripon, San Joaquin County
<br /> 1. Distance to production wells for municipal, domestic, agriculture, Due to the limited extent of soil-only contamination,
<br /> industry and other uses within 2000 feet of the site; well survey was not required.
<br /> 2. Site maps, to scale, of area impacted showing locations of former and existing tank Piping from the USTs was
<br /> systems, excavation contours and sample locations, boring and monitoring well removed during a dispenser
<br /> elevation contours, gradients, and nearby surface waters, buildings, streets, and upgrade in September 2002.
<br /> subsurface utilities;
<br /> Q3. Figures depicting lithology(cross section), treatment system diagrams; Site lithology consists of sand,sift, and clay to
<br /> 32 feet, the total depth investigated.
<br /> 4. Stockpiled.soil disposed off-site(quantity); An unknown quantity of excavated soil and piping were taken to
<br /> Forward Landfill,Manteca.
<br /> 0 5. Monitoring wells remaining on-site, fate;
<br /> Monitoring wells were not required or installed.
<br /> 0 6. Tabulated results of all groundwater elevations and depths to water, The depth to water was 28 feet and the regional
<br /> groundwater Row direction is to the north.
<br /> 0 7. Tabulated results of all sampling and analyses: Soil samples collected at the time of the piping removal reported
<br /> Y® TPHg, 1,600 mg/kg, TPHd, 18,000 mg/k, benzene, <0.01 mg/kg;toluene,Detection limits for confirmation sampling <0.01 mg/kg,ethylbenzene, 0.14 mg/kg,xylenes, 0.96 mg/kg,and MtBF,
<br /> Lead analyses <0.01 mg/kg under the piping. Soil samples collected at 5-foot
<br /> Intervals from 5 to 30 feet were all non-detect for all constituents.
<br /> Groundwater grab sample results were non-detect for all constituents.
<br /> 8. Concentration contours of contaminants found and those remaining in soil
<br /> and groundwater, both on-site and off-site: The piping excavation soil samples and on-
<br /> Lateral and Vertical extent of soil contamination site soil borings define the extent of
<br /> Lateral and Vertical extent of groundwater contamination contamination.
<br /> 0 9. 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 /> 10.Reports/information Y❑ Unauthorized Release Form 19 OMRs
<br /> Boring logs PAR N❑ FRP F1 Other
<br /> 11.Best Available Technology(BAT)used or an explanation for not using BAT;
<br /> Remove soft and natural attenuation.
<br /> Y 12.Reasons why background waslis
<br /> unattainable using BAT, Minor soil contamination remains on-site. I
<br /> N� 13.Mass balance calculation of substance
<br /> treated versus that remaining; Mass balance was not calculated for soil or groundwater.
<br /> E14.Assumptions,parameters, calculations and model used in risk
<br /> assessments, and fate and transport modeling;and A risk assessment was not required.
<br /> 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 samples show no impact from soil
<br /> contamination.
<br /> By: Comments: Piping was removed during a piping and dispenser upgrade from the subject site in 9102. Minor soil
<br /> JLB contamination was identified under the piping. Excavated soil was transported to Forward Landfill, Manteca. Five borings
<br /> and live grab groundwater sample were completed around the dispensers to delineate contamination at this site. The
<br /> Date: borings and grab groundwater samples did not detect additional contamination in soil or in groundwater. Based on the
<br /> minor soil contamination and lack of contamination in groundwater, Regional Board staff concur with San Joaquin
<br /> 7121103 County's Closure Recommendation.
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