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'M ULE 1 -CHECKLIST OF REQUIRED DATA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES ,
<br /> f Site Name and Location:. San Joaquin Catholic Cemetery, Hardin Ave.&Cemete Ln. Stockton, C
<br /> !3 ry ckton, San Joaquin County
<br /> (Lustis Case#390444)
<br /> y 1. Distance to production wells for municipal, domestic, agriculture, A well survey in 2000 reported 5 wells:one 40 ft. i
<br /> industry and other uses within 2000 feet of the site. south of USTs;and 500 ft west, 700 ft north, 900 ft {
<br /> south,and 1500 ft west of the site.
<br /> y 2. Site maps, to scale, of area impacted showing(locations of any former One 500 gallon and one 1,000-gallon gasoline iM
<br /> and existing tank systems, excavation contours'Land sample locations, USTs were removed 11/89. The 1,000-gallon US;T
<br /> boring and monitoring well elevation contours, gradients, and nearby suffered a catastrophic failure,
<br /> surface waters, buildings, streets, and subsurface utilities; r
<br /> Y 3. Figures depicting lithology(cross section);Itleatment system diagrams; Site lithology consists of clay,silt,and sand i
<br /> i to 151 feet, the total depth investigated f
<br /> :Y:1 4. Stockpiled soil remaining on-site or off-site disposal(quantity); The fate and amount of soil removed was not specifie,'d
<br /> Y5. Monitoring wells remaining on-site, fate; Nine monitoring wells(MW-'l through MW-9)remaining on-site will be !
<br /> ro erl abandoned. :; ;l
<br /> 8. Tabulated results of all groundwater ' Depth to groundwater varied from 34 to 70 feet below ground surface.ji
<br /> -.T.he: roundwater gradient varied-from 0.00'1 to 0.005 ft/ft--and-the
<br /> elevations and depths fa water $" 4 -`" g
<br /> ~. downgradient direction;varied from North to Northeast
<br /> 7. Tabulated results of all sampling In 1191,maximum soil concentrations were TPHg, 12,000 mg/kg;benzene,
<br /> and analyses: 26-mg/kg;.toluene;970 mglkg;ethylbenzene, 230 mg/kg;and xylenes, 710 mg/kg"
<br /> Y❑ In 8100;maximum soil concentrations were TPHg, 560 mg/kg;and MtBE, 0.1 mglkg.Detection limits for confirmation Maximum groundwater concentrations in 5197 were TPHg, 12,000 ug/L;benzene]
<br /> sampling 14 ug/L;,toluene, 2,400 ug/L;ethylbenzene, 500 ug/L;and xylenes, 1,900 ug/L;with
<br /> MtBE; 1;800 pg/L (8197);and 1,2-DCA,37 ug/L(12197). In 12/05,maximum
<br /> N❑ Lead analysesgroundwater concentrations were MtBE, 52 ug/L and 1,2-DCA, 12 ug/L.
<br /> LYJ 8. Concentration contours of contaminants'found and those remaining in sail The extent of contamination is adequately'l
<br /> and groundwater, and both on-site and off-site: '; defined by soil borings and monitoring
<br /> wells.
<br /> 0 Latera!and 0 Vertical extent-of soil contamination
<br /> FYI Latera!and Vertical extent of groundwater contamination
<br /> 9. Zone of influence calculated and assumptions;used for subsurface SVE,batch groundwater extraction, and
<br /> remediation system and the zone of capture'attained for the soil and natural attenuation were the selected
<br /> roundwater remediation system; t remedial actions for soil and groundwater,
<br /> 10.Departs/infom�ation ❑Y Unauthorized Release Form ❑Y QMRS(48 from 8190 to 12105)
<br /> tr r
<br /> ❑ PAR ❑.FRP ❑y Other, Site Conceptual Model/Request for Closure
<br /> ❑y Well and boring logs
<br /> Y 11.Best Available Technology(BAT)used or an explanation for not using BAT; Removal of USTs, SVE,batch
<br /> E groundwater extractions, and natural
<br /> f
<br /> attenuation. E
<br /> Limited soil contamination and groundwater_pollution ..
<br /> Y 12.Reasons why background wads unattainable'using.BAT,•s, _= .
<br /> —. .. rernarns on-site.
<br /> Y 13.Mass balance calculation of substance treated versus That
<br /> In 2006, the consultant estimated TPHg, 86 gallons remain'
<br /> remalnin ; : r . soil,and MtBE, 0.13 lbs remain in groundwater. M
<br /> Y 14. Assumptions, parameters, calculations and model used Soil ESLs were exceeded for TPHg. The Water Quality Goal
<br /> in risk assessments, and fate and transport modeling ; (WQG)is exceeded for MtBE and 1,2-DCA. A Tier 2 RBCA''
<br /> assessment and groundwater modeling showed no adverse
<br /> effects to wells or human health.
<br /> y 15. Rationale why conditions remaining of site will not Soil contamination is limited in extent. Results of 48
<br /> adversely impact water quality, health, or other beneficial quarters of groundwater monitoring show a decreasing
<br /> uses;and trend in concentrations. The consultant estimated WQGs }
<br /> ,- should be leached by 12108. :i
<br /> By: JLB Comments: One 500 gallon and one 1„000-gallon gasoline USTs were removed 11189. The 1,000-gallon UST '
<br /> suffered a catastrophic failure. Site is primarily open land.!kS VE removed over 1,600 gallons of TPHg from r
<br /> Date: soil. The Site irrigation wellwas ND for the last 23 sampling events. Based upon 48 quarters of declining ik
<br /> 8/9/2007 groundwater concentrations,a.RSCA assessment which evaluated all pathways,a groundwater model which
<br /> showed no impacts to wells,and the limited extent of contamination present in soil and groundwater, u i
<br /> Regional Board staff concur with San Joaquin County's Closure Recommendation. 3
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