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<br /> QBLE 1 -CHECKLIST OF REQUIRED DATA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and location: Navarra Property Former Fueling Station, 7500 W. Eleventh St. Tracy, San.Joaquin County
<br /> (RB#390773)
<br /> ___1 1. Distance to production wells for municipal, A 2001 sensitive receptor survey reported 20 water supply wells
<br /> domestic, agriculture, industry and other uses within within 2,000'of the Site. The nearest wells are onsite 100'from
<br /> 2000 feel of the site. I US Ts. None of the wells are threatened by the release.
<br /> Y 2. Site maps, to scale, of area impacted showing locations of any former In 12-98, four 1,000-gallon unknown product, one
<br /> and existing tank systems, excavation contours and sample locations, 2,000-gallon gasoline, one 5000-gallon gasoline,
<br /> boring and monitoring well elevation contours, gradients, and nearby one 3,500-gallon diesel,and one 10,000-gallon
<br /> surface waters, buildings, streets, and subsurface utilities; diesel USTs were removed.
<br /> Y 3. Figures depicting lithology(cross section), treatn7ent Site lithology consists of clay,silt,and sand to 55', the total depth
<br /> system diagrams; investigated.
<br /> Y 4. Stockpiled soil remaining on- approximately 521.25 tons of excavated soil was transported to Forward Landfill in
<br /> site or off-site disposal uanti • Manteca.
<br /> MW-12A and MWFP-1
<br /> MW-19 MW-3a MW-3B,
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<br /> 5. Monitoring wells All monitoring wells(MW-1 through ,
<br /> remainin on-site, fate; through MWFP-5)will be properly destroyed prior to closure.
<br /> YJ 6. Tabulated results of all groundwater Depth to groundwater varied from 2'bgs to 11'bgs. Groundwater flow
<br /> elevations and de the to water, direction was towards the northeast. Groundwater gradient was 0.003 ft(ft.
<br /> 7. Tabulated results of all sampling - All data adequately tabdlarized in various rteports:and analyses:
<br /> QDetection limits for confirmation
<br /> sampling
<br /> �Y 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 /> ElLateral and Vertical extent of soil contamination
<br /> Lateral and F1 Vertical extent of ggroundwater contamination
<br /> 9. Zone of influence calculated and assumptions used for subsurface Over-excavation and free product removal
<br /> remediation system and the zone of capture attained for the soil and (FPR) were the engineered remediation.
<br /> groundwater remediation system;
<br /> 14.Reports 1 information EY Unauthorized Release Form QMRs(33)5-00 to 7-11
<br /> FY] Well and boring logs 10 PAR FRP Other Closure Report, 6-12
<br /> YJ 11.Best Available Technology(BAT) used or an explanation USTs removal,soil over-excavation,FPR and natural
<br /> for not using BAT; I attenuation.
<br /> UY 12. Reasons why background was/is Residual soil and groundwater contamination remains.
<br /> ttainable using BAT,'
<br /> Y 13.Mass balance calculation of substance Consultant estimated initial mass as 5,3961bs. TPN in soil and 0.29 lbs.
<br /> -- - treated-versus-that-remaining, _ TPH in groundwater.approximately 957 lbs.of TPN remain in soil and
<br /> w ' 0.06T s P11 rema-;n- roundwater.- - "
<br /> -7Y 14. Assumptions, parameters, calculations A soil vapor survey was not required by the regulatory agency. With one
<br /> and model used in risk assessments, and fate exception(PP-7 at 4'bgs exceeded Region 2 ESLs for TPHg, TPHd and
<br /> and transport modeling; BE)0, soil was over-excavated to 7'bgs(dispenser)and 9'bgs(tanks),
<br /> which is below typical worker exposure depths. Consultant states site
<br /> does not represent a significant risk.
<br /> 7Y 15. Rationale why conditions remaining at site Soil and groundwater contamination reportedly are limited in extent.Land
<br /> will not adversely impact water quality, health, 'use(commercial)is not expected to change in the foreseeable future.
<br /> or other beneficial uses;and Based on data trend line analysis, WQGs will be reached bX 2027.
<br /> By: JLC/ p Comments:In 12-98, four 1,000-gallon unknown product, one 2,000-gallon gasoline, one 5000-gallon
<br /> gasoline, one 3,500-gallon diesel,and one 10,000-gallon diesel USTs were removed at the subject site.
<br /> Date: Residual soil contamination remains.Based upon the limited extent of contamination reported in soil and
<br /> 1/31/2013 groundwater,groundwater estimated to reach WQGs in 12 years, no foreseeable changes in future land use
<br /> (commercial), and minimal risks from groundwater,soil vapor and soil, Regional Board staff concur with
<br /> San Joaquin County's Closure Recommendation.
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