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�-�ABLE 1 -CHECKLIST OF REQUIRED DATA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and Location: USA Petroleum#3698/Tesoro#67080, 2449 Kettleman Ln., Lodi,San Joaquin County'(RB#391161)
<br /> Y 1. Distance to production wells for municipal, domestic, Two municipal supply wells were identified 1700'east
<br /> agriculture, industry and other uses within 2000 feet of the site. and 1700'west,respectively, of the-Site,
<br /> Y 2. Site maps, to scale, of area impacted showing locations of The source of the release(#2) was not identified during
<br /> any former and existing tank systems, excavation contours and the investigation. However, case#1 (USTs release) was
<br /> sample locations, boring and monitoring well elevationlosed by the SJCEHD in 8/97 after completion of
<br /> contours, gradients, and nearby surface waters, buildings, mediation(soil excavation and SVE).
<br /> streets, and subsurface utilities;
<br /> Y1 3. Figures depicting lithology(cross section), treatment system Site lithology consists of clay, silt,and sand to 60', the
<br /> diagrams; total depth investigated.
<br /> :71 4. Stockpiled soil remaining on-site or off-site disposal(quantity); The reports do not discuss soil excavation or disposal.
<br /> N 5. Monitoring wells remaining on-site, fate; Three monitoring w ils(MW-1 through MW-3) were installed 12/03 as a result
<br /> of a property transf r Phase 2 investi ation.
<br /> 6. Tabulated results of all groundwater Depth to group water varied from 46'to 50'bgs. Groundwater flow
<br /> elevations and.de the to water, direction varied rrom west to southeast
<br /> - -7.`Tabulate'd results of all'sampling"lig 12/03-the soil boring rri ximum concentrations-were'TPHd,1�2-mg/kg;TAME;
<br /> and analyses: 0.42 mg/kg; TBA, 0.012 m /kg;and MTBE, !1 mg/kg. Additional soil borings were
<br /> not collected after the wei Is were installed. On 5104. maximum groundwater
<br /> 0 Defection limits for confirmation monitoring results were T Hd, 320 ug/L;MTBE, 690 ug/L; TAME 3.7 ug/L;and
<br /> sampling TPHg(10104), 140 ug/L. 0111108, the only groundwater monitoring result was
<br /> MTBE, 1.4 ug/L.
<br /> 0 Lead analyses
<br /> Ly J $, Concentration contours of contaminants found and those remain'ng in soil and The extent of the identified
<br /> groundwater, and both on-site and off-site contamination is described in the
<br /> reports.
<br /> YLateral and i Vertical extent of soil contamination
<br /> Lateral and MY Vertical extent of groundwatercontamination
<br /> 9. Zone of influence calculated and assumptions used for subsurface remediation An engineered remediation.was not
<br /> system and the zone of capture attained for the soil and groundwa.ter remediation required by the lead agency.
<br /> system;
<br /> 10.Reports/information EY Unauthorized Release Form ❑Y QMRs 17 from 12103 to.11108
<br /> Qy Well and boring logs Qy PAR [N-1 FRP b ther Case Closure Summary Report(12/07)
<br /> YJ 11.Best Available Technology(BAT) used or an explanation for not q5ing TWonitored natural attenuation.
<br /> BAT,'
<br /> Y 12. Reasons why background was/Is unattainable Minor residut 1 soil and groundwater contamination remains on-site.
<br /> BAT-
<br /> 93.JV1ass_balancetreafed Remaining M BE mass was estimated by the consultant in 2007 as
<br />— r Y- _calculation_of_substance_ 77.37bs in so t and�U.000776s!n groundwater:�"""�'�--��
<br /> versus that remainin ,
<br /> 7Y 14. Assumptions, parameters, calculationsand Soil sample sults show Region 2 ESLs were not exceeded. The site
<br /> model used in risk assessments, and fate and is an actives arvice station in a commercial area of Lodi.
<br /> transport rnodelin ;
<br /> Y 15. Rationale whyconditions remaining at site will Soil contami ation reportedly is limited in extent. Land use(service
<br /> not adversely impact water quality,health, or other station in co mercial area)is not expected to change in the
<br /> beneficial uses;and foreseeable f iture.
<br /> By: JLB Comments: Three monitoring wells(MW-1 through W-3) were installed 12/03 as a result of a property
<br /> transfer(Phase 2)investigation at the subject site. The source of the contamination was not identified
<br /> Date: during the investigation. In 12103 the soil boring mg ximurn concentrations were TPHd, 12 mg/kg; TAME,
<br /> 4/29/2009 0.42 mg/kg; TBA, 0.012 mg/kg and MTBE, 11 mg/kg. Additional soil borings were not collected after the wells
<br /> were installed. On 5104. maximum groundwater mo Wtoring results were TPHd,320 ug/L;MTBE, 690 ug/L;
<br /> TAME 3.7 ug/L;and TPHg(10104), 140 ug/L. On 111(8, the only groundwater.monitoring result was MTBE,
<br /> 1.4 ug/L. Minor residual soil and groundwater contamination remains on-site. Based upon 17 quarters of
<br /> groundwater monitoring, the limited extent of confa wination reported in soil and groundwater, no
<br /> foreseeable changes in land use,and no ESLs exceeded, Regional Board staff concur with San Joaquin
<br /> County's Closure Recommendation.
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