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TABLE 1 - CHECKLIST OF REQUIRED DATA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> rite Name and Location Regal #603,6425 Pacific Avenue,Stockton,San Joaquin County
<br /> A well receptorOurvey was carnpfeted in
<br /> Y 1 Distance to production wells for municipal, domestic, agnculturs. in 1998. Three existing water supply wells
<br /> and other uses within 2000 feet of the site, are within 2,000 feet of the site.
<br /> Three l oo04-gallon gasoline
<br /> 2 Site maps, to scale, of area impacted showing locations of former and existing tank systems, USTs were removed and
<br /> excavation contours and sample locations,boring and monifonng well elevation contours, replaced fn October 1988.
<br /> gradients,and nearby surface waters,buildings.streets,and subsurface utilrtres; Site reaps provided
<br /> Lithology figures show a shallow sand
<br /> 3 Figures depicting 1100109Y(cross sectlon), treatment system diagrams, aquifer overlain with silty clay sediments
<br /> Excavated soils associated VV,jh the USTs were returned
<br /> i
<br /> N 4 Stockpiled soil remaining on or oft life disposal(quantlty}, to the�k pit rz� e �.. -
<br /> 5 Monitonng wells remaining on-site, fate; Thirteen monitoring wells remain on-site and oft-site
<br /> Groundwater elevations vary from 33 to 60 feet bgs,
<br /> 6 Tabulated results of all groundwater elevations and depths to water; and groundwater flow is eastlnortheast
<br /> EE 7 Tabulated results of all sampling and analyses January 1939 maximum groundwater monitoring results InY94 Show
<br /> TpHg at 5,400, benzene at 7, toluene at!55,ethyl benzene at 170,
<br /> ElDetection limrts for confirmation sampling Xylenes at 1100,and MtBE at IB. lead was identified at 12 mg/k9 in
<br /> Lead analyses one overexcavatlon$oil sampre.
<br /> © of
<br /> 8 Concentratidn contours of contaminants found and those remaining in sari The vertical and lateral extent
<br /> � groundwater contamination has
<br /> not been
<br /> and groundwater,and both on-site and off-site defined.
<br /> Y❑ Lateral and © Vertical extent of soil contamination
<br /> ❑ Lateral and Vertical extent of groundwater contamination
<br /> N A SVE system operated from October 1991
<br /> 9 Zone of influence calculated and assumptions used for subsurface to December 1998,and an air sparging
<br /> remediation system and the zone of capture attairred�Er a s system operated from December 1997 to
<br /> W Z
<br /> groundwaterremediahon system, yip► �s��� peaembier 1998.
<br /> 10 Reports/information 0 Unauthorized Release Form 0 QMRs (8191 through 1/99)
<br /> El Welland boring logs EI PAR FRP
<br /> other(Qverexcavatron of Soils, 4100)
<br /> Free roduet removal, followed by SVE and
<br /> BA used or an explanation for not using SAT, p
<br /> 0 1 i Best Available Technology( T} air sparging
<br /> Contamination remal{is rn ori-site softs,and the
<br /> 12 Reasons why background warms unattainable using BAT, groundwater plume has extended off-site.
<br /> A mass balance completed in 1398 estimated 90
<br /> 13 Mass balance calculation of substance treated versus that remaining, pounds of TPHg and i pound of benzene
<br /> remaining In groundwater.
<br /> 0 calculations and model used In nsk A RBCA evaluation was completed using the Tier 2 14 Assumptions,parameters, assessment.assessments,and fate and transport modeling,
<br /> Consultant states that 9996 of the benzene,and 6396 of
<br /> 15 Rationale why conditions remaining at site will not adversely the TPlfg has been removed,and removal rates have
<br /> Impact water quality,health, or other beneficial uses decreased to asymptatlo levels. However,the extent of
<br /> contaatlnatlon In undwrrier hes not been defined
<br /> gy; Comments: 7l►raa USTs were re o d mills MIrJ-8 anIn d MW-!2 at concentrations a than!n7 fte wet by 8
<br /> TPHg is
<br /> detected in doxnrgradre g
<br /> ]'rKl 000 feet oft e
<br /> Benzene and ME concentrations are Jaw A well surrey�as completed, and three wells are within 2, wafer is
<br /> site The closest we!!!s a i20-foot deep damestre ane!► ornxrmateiy 9b0 feet southeast of the site. City
<br /> MW-
<br /> e: supplied,and it Is unknown d the domestic vier!is actno7 The extent of groundwater contamination beyond MW-12 has
<br /> not been defined The on-site groundwaterplume app&ars to bs stable;however, the last groundwater ,San daquin
<br /> I` 00 completed mpleted In 1/99 after the SVE and air sparging systems Svere shut Ba
<br /> ut osed on lnforrnatfon provided.San
<br /> County's closure recommendation is not appropnate at this 1,me
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