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<br /> 4-(ABLE 1 -CHECKLIST OF REQUIRED DATA\, '
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and Location: Former Moore Petroleum, 5491 F St.Banta,San Joaquin County(RB#390255)
<br /> y 1 1. Distance to production wells for municipal,domestic, A 2006 sensitive receptor survey reported one public, one
<br /> agriculture, industry and other uses within 2000 feet of the irrigation and 31domesic water supply wells(nearest 100'
<br /> site. east)within 2,000'of the Site. The wells are not threatened
<br /> by this release.
<br /> Y 2. Site maps, to scale, of area impacted showing locations of any former From 8-98 to 9-98, three 10,000-gallon diesel, four
<br /> and existing tank systems, excavation contours and sample locations, 10,000-gallon gasoline, one 350-gallon cleaning
<br /> boring and monitoring well elevation contours, gradients, and nearby solvent,and one 350-gallon kerosene USTs were
<br /> surface waters, buildings, streets, and subsurface utilities; removed.
<br /> _71 3. Figures depicting lithology(cross section), treatment system diagrams; Site lithology consists of clay,silt,sand, and
<br /> gravel to 80, the total depth investigated.
<br /> Y 4. Stockpiled soil remaining on-site or off-site disposalApproximately 300 yds. of over-excavated soil was later
<br /> (quantity); utilized as backfill on top of 3'of clean backfill.
<br /> Y 5. Monitoring wells remaining on-site, Sixteen(16)monitoring wells(MW-1 through MW-3, MW-4A, MW-5, MW-6,
<br /> a e; MW-9 through MW-18), two(2)monitoring/remediation wells(MW-7/VEW--4 and
<br /> MW-8/VEW--3)and thirteen(13)remediation wells(RW-2, VEW-1, VEW-2, OS-1
<br /> through OS-10)will be properly destroyed.
<br /> 6. Tabulated results of all groundwater Depth to groundwater varied from 6'bgs to 13'bgs. Groundwater now direction
<br /> elevations and depths to water, - was-towards the northeast. Groundwater gradient varied from 0.0019 ft/ft to
<br /> 0.0062 ft(ft.
<br /> ELI 7. Tabulated results of all sampling All data adequately tabularized in various reports,including closure report.
<br /> and analyses:
<br /> FYI Detection limits for confirmation
<br /> sampling
<br /> QY Lead analyses
<br /> 8. Concentration contours of contaminants found and those remaining in The extent of the identified contamination is
<br /> soil and groundwater, and both on-site and off-site: described in the available reports.
<br /> Y❑Lateral and Y❑Vertical extent of soil contamination
<br /> Lateral and MY Vertical extent of groundwater contamination
<br /> 9. Zone of influence calculated and assumptions used for subsurface Over-excavation,soil vapor extraction(SVE)
<br /> remediation system and the zone of capture attained for the soil and and ozone sparging(OS)were the engineered
<br /> groundwater remediation system; remediation.
<br /> 10.Reports/information QY Unauthorized Release Form QY QMRs(72) 1-92 to 1-11
<br /> FYI Well and boring logs 10 PAR 151FRP 10 Other Closure Report(9-11)
<br /> Y11.Best Available Technology(BAT) used or an explanation USTs removal, over-excavation, SVE, OS,and natural
<br /> for not using BAT; attenuation.
<br /> Y 12. Reasons why background was/is unattainable Residual soil and groundwater contamination remains.
<br /> gr-BAT -
<br /> 77 13.Mass balance calculation of substance treated Consultant estimated 110.45 lbs. of TPH remain in soil and
<br /> versus that remaining; 1.48 lbs. of TPH remain in groundwater. SVE removed 7,844.2 lbs.
<br /> of TPH.
<br /> Y 14. Assumptions, parameters, calculations and A 2011 soil vapor survey failed Commercial Region 2 ESLs for
<br /> 7
<br /> model used in risk assessments, and fate and TPHg but passed a Tier 2 RISC4 model. Soil failed ESLs for direct
<br /> transport modeling; exposure(DE)and gross contamination for TPHg and TPHd at
<br /> 8'bgs and DE for Benzene at 10'bgs, which is below typical worker
<br /> depths. Consultant states site does not represent a significant risk.
<br /> Y 15. Rationale why conditions remaining at site will Soil and groundwater contamination reportedly are limited in
<br /> not adversely impact water quality, health, or other extent.Land use(commercial)is not expected to change in the
<br /> beneficial uses;and foreseeable future. Time to reach WQGs estimated as 2050.
<br /> By: JLBComments:From 8-98 to 9-98, three 10,000-gallon diesel, four 10,000-gallon gasoline, one 350-gallon
<br /> cleaning solvent, and one 350-gallon kerosene USTs were removed at the subject site. Residual soil and
<br /> Date: groundwater contamination remains. Based upon the limited extent of contamination reported in soil and
<br /> 12/5/2012 groundwater, groundwater reaching WQGs in a reasonable time frame,no foreseeable changes in future
<br /> land use(commercial), and minimal risks from groundwater,soil vapor and soil, Regional Board staff concur
<br /> with San Joaquin County's Closure Recommendation.
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