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TA b9eE 1 - CHECKLIST OF REQUIRED ., TA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and Location: Emil's Liquor, 1405 California Street, Escalon, San Joaquin County
<br /> 1. Distance to production wells for municipal, domestic, agriculture, A sensitive receptor survey conducted in 11/05
<br /> industry and other uses within 2000 feet of the site; reported one public supply well located 1700'south of
<br /> the site.
<br /> 2. Site maps, to scale, of area impacted showing locations of former and existing tank Two 5,000-gallon unleaded
<br /> systems, excavation contours and sample locations, boring and monitoring well elevation gasoline, one 2,000-gallon
<br /> contours, gradients, and nearby surface waters, buildings, streets, and subsurface utilities; diesel,and one 85-gallon waste
<br /> oil USTs were removed in 7/97.
<br /> y�
<br /> 3. Figures depicting lithology(cross section), treatment system diagrams; Site litho/ogy consists of sand,silt and clay.
<br /> The total depth investigated was 60 feet.
<br /> 4. Stockpiled soil disposed off-site(quantity); An unspecified amount of soil was excavated,aerated, and spread
<br /> onsite.
<br /> 0 5. Monitoring wells remaining on-site, fate;
<br /> No monitoring wells were installed for this investigation.
<br /> 6. Tabulated results of all groundwater elevations and depths to water, The depth to water was approximately 59 feet. The
<br /> estimated groundwater flow direction is to the
<br /> northwest,based on 1405 Escalon Ave.
<br /> 0 7.Tabulated results of all sampling and analyses: In 7/97, confirmation samples from the USTs dispenser and piping
<br /> excavation reported TPHg(2.5 mg/kg), TPHd(140 mg/kg),benzene
<br /> Y®Detection limits for confirmation sampling (0.14 mg/kg), toluene(0.75 mg/kg), ethy/benzene(0.07 mg/kg),xylenes
<br /> Y Lead analyses (0.73 mg/kg),and MtBE(80 mg/kg). In 2/99,all soil borings results
<br /> were ND. In 3/00,all grab groundwater results were ND.
<br /> YE 8. Concentration contours of contaminants found and those remaining in soil The extent of soil pollution is defined by
<br /> and groundwater, both on-site and off-site: on-site soil borings.
<br /> PLateral and �Y Vertical extent of soil contamination
<br /> Lateral and Vertical extent of groundwater contamination
<br /> FE 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/informationY❑ Unauthorized Release Form NQMRs
<br /> 0 Boring logs El PAR 0 FRP 0 Other (Closure Summary Report, 11/05)
<br /> 11.Best Available Technology(BAT) used or an explanation for not using BAT, Remove UST,soil aeration,and natural
<br /> attenuation.
<br /> a12.Reasons why background wasfis
<br /> unattainable using BAT, Minor soil pollution remains on-site.
<br /> 13.Nass balance calculation of substance The consultant estimated 1 gallon of TPHg remain in soil down to 10 feet below
<br /> treated versus that remaining;
<br /> ground surface at the site. A subsequent rupture of a product line released
<br /> 6.88 gallons of TPHg during the investigation.
<br /> 0 14.Assumptions,parameters, calculations and model used in risk
<br /> assessments, and fate and transport modeling,and A risk assessment was not required. No Region 2 ESLs
<br /> were exceeded.
<br /> 0 15. Rationale why conditions remaining at site will not adversely Soil contamination is limited in extent,and based on
<br /> impact water quality, health, or other beneficial uses. maximum depth of contamination(10')and the depth to
<br /> water(over 589, contamination will probably not reach
<br /> groundwater.
<br /> By: Comments: Two 5,000-gallon unleaded gasoline, one 2,000-gallon diesel, and one 85-gallon waste oil USTs were
<br /> JLB removed in 7/97 from the subject site. Multiple borings were completed 01998 and 1999, to delineate contamination at
<br /> this site. In 7/97, confirmation samples from the USTs dispenser and piping excavation reported TPHg(2.5 mg/kg), TPHd
<br /> Date: (140 mg/kg), benzene(0.14 mg/kg), toluene(0.75 mg/kg), ethylbenzene(0.07 mg/kg), xylenes(0.73 mg/kg), and MtBE
<br /> (80 mg/kg). In 2199, all soil borings results were ND. In 3/00, all grab groundwater results were ND. Based on the limited
<br /> 12/27/2005 extent of soil contamination and minimal threat to groundwater, Regional Board staff concur with San Joaquin County's
<br /> Closure Recommendation.
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