Laserfiche WebLink
r <br /> TA�.,= 1 - CHECKLIST OF REQUIRE ATA <br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES <br /> Site Name and Location: City of Stockton Municipal Utilities District, Royal Oaks and Princess Street,Stockton, <br /> San Joaquin County <br /> FqA—1 1. Distance to production wells for municipal, domestic, agriculture, industry Initial contamination limited only to soil. <br /> and other uses within 2000 feet of the site• No contamination detected during 1999 <br /> site investigation. <br /> 0 2. Site snaps, to scale, of area impacted showing locations of former and existing tank systems,- One 1,500-gal diesel UST <br /> excavation contours and sample locations, boring and monitoring well elevation contours, was removed in 1994. <br /> gradients, and nearby surface waters, buildings, streets, and subsurface utilities; <br /> 0 3. Figures depicting lithology(cross section), treatment system diagrams; The lithology consists of sand and silt <br /> 0-30'bgs and clay>.10'bgs. <br /> NA 4. Stockpiled soil remaining on-site or off-site disposal(quantity); No soil stockpile generated. <br /> NA 5. Monitoring wells remaining on-site, fate; No monitoring wells were installed, soil borings only. <br /> NA _ <br /> 6. Tabulated results of all groundwater elevations and depths to wafer,' Groundwater elevations varies between 35 and 55' <br /> bgs, with an estimated NE flow direction. <br /> 7 Tabulated results of all sampling and analyses: A diesel tank was removed in 1994 and soil samples collected below <br /> y the former tank. Xylene at 300 pg/kg and TPHd at 64,000 pg/kg were <br /> Defection limits for confirmation sampling detected,and the pit was backfilled. <br /> NA Lead analyses <br /> NA 6. Concentration contours of contaminants found and those remaining in sot! In the summer of 1999, three borings were <br /> d groundwater, and b site and off--site: installed near the former tank pit and <br /> NA Lateral and LF_N__A1j Vertical extent of soil contamination advanced to 45'bgs. Soil and groundwater <br /> NA NA Lateral and Vertical extent of groundwater contamination samples were ND for TPHd,BTEX,and <br /> MtBE. <br /> FAI 9. Zone of influence calculated and assumptions used for subsurface <br /> remedlation system and the zone of capture attained for the soil and <br /> groundwater remediation system; <br /> Y� 10.Reports/information Unauthorized Release Form NA QMRs(Dates) <br /> Well and boring logs NA PAR NA FRP Other(report name) 1999 Soil& GW Invest. Summary <br /> 11.Best A vailable Technology(BAT) used or an explanation for not using BAT; Natural attenuation � <br /> _ - �» NA '12:Reasons why background ivasrs unattainable using BAT, ' —Soil borings were ND.i- -�-- - -; <br /> 13.Mass balance calculation of substance treated versus that remaining; No estimate of amount released. Samples <br /> were ND in 1999. <br /> i <br /> 14.Assumptions,parameters, calculations and model used in risk <br /> assessments, and fate and transport modeling; <br /> a15.Rationale why conditions remaining at site will not adversely The soft consists of slits and clays at depth. Any <br /> impact water quality, health, or other beneficial uses;and remaining residual diesel is likely confined on-site below <br /> the former tank. Groundwater is not impacted. <br /> r <br /> NA 16.WET or TCLP results <br /> By.�/^ � Comments:in May 1994, one 1,500-gallon diesel tank was removed from the site. Elevated levels of TPHd and <br /> I'� 45 xylene were detected in soil during tank removal. In 1999, three soil borings were installed in the vicinity of the <br /> Da : former tank site to 45 feet bgs;groundwater was encountered at 35 feet bgs. Soil and groundwater samples results <br /> were nondetect for TPHd, BTEX, and MtBE. Based on the information provided and site conditions, staff concurs <br /> lG �� with San Joaquin County's closure recommendation. <br />