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TABL1 -CHECKLIST OF REQUIRED. DA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and location: Tracy Community Memorial Hospital, 1420 Tracy Boulevard, Tracy, San Joaquin County
<br /> As provided by the County, the nearest municipal well
<br /> 1. Distance to production wells for municipal, domestic,agriculture,
<br /> is approximately 1,000 feet southeast of the site.
<br /> industry and other uses within 2000 feet of the site;
<br /> 2. Site maps, to scale, of area impacted showing locations of former and-existing tank systems, Two diesel USTs were
<br /> 0 excavation contours and sample locations, boring and monitoring well elevation contours; removed in 9/88, and one
<br /> gradients, and nearby surface waters, buildings, streets,.and subsurface utilities; gasoline UST was closed in
<br /> . _ place in 2/90.
<br /> Boring logs show silty sand to 34 feet, the total
<br /> Y� 3. Figures depicting lithology(cross section), treatment system diagrams; depth investigated.
<br /> f y 4. Stockpiled soil disposed off-site(quantity); approximately 92 tons of contaminated soil was excavated from the
<br /> diesel tank pit and disposed off-site.
<br /> 4 Three monitoring wells remain on-site. The wells will be properly destroyed
<br /> 5. Monitoring wells remaining on-site, fate; pending site closure.
<br /> below
<br /> j 6. Tabulated results of a1l groundwater elevations and depths to water,' ground surface,and flGroundwater levels vaoried from 9 to 16 feet
<br /> w is to the west/northwest
<br /> 7. Tabulated results of all sampling and analyses: Maximum.-soil contamination showed TEPH as diesel at 3,000 mg/kg
<br /> and motor oil at4,400 mg/kg. Soil contamination was excavated and
<br /> A
<br /> Defection limits for confirmation sampling disposed off site. Lead was not detected! X1
<br /> at .0 mg/kg. The three
<br /> 0
<br /> Lead analyses monitoring wells were sampled in 5/95 and 8/95, and no TPH or BTEX
<br /> constituents were detected in groundwater.
<br /> 8. Concentration contours of contaminants found and those remaining in soil `The extent of soil contamination was
<br /> Y defined, then excavated and removed from
<br /> and off-site:
<br /> and roundwater, and both on-site
<br /> 9the site. Groundwater contamination was
<br /> Lateral and Y1 Vertical extent of soil contamination not identified:
<br /> E'
<br /> Lateral and ❑ Vertical extent of groundwater contamination
<br /> r 9.Zone of influence calculated and assumptions used for subsurface Based on the limited contamination,site
<br /> Qremediation system and the zone of capture attained for the soil and remediation beyond soil excavation and
<br /> groundwater remediation system; disposal was not required.
<br /> 10.Reports/information Unauthorized Release Form F QMRs
<br /> 0 Boring logs ' � PAR FRP Other
<br /> 0 11.Best Available Technology(BAT) used or an explanation for not using BA T; The USTs and contaminated soils were
<br /> removed.
<br /> i
<br /> Y� ..12.;Reasons;sti�hy.backgrou.,d wads� Soil.contamir±ation,.evas.excavatad.and-dls0sed off-site. G;oc:ncl�vater' "-
<br /> contamination was not identified.
<br /> unattainable using BAT,'
<br /> Y� 13.Mass balance calculation of substance Based on the removal of contaminated soils and no groundwater
<br /> treated versus that remaining; contamination, an estimate of the remaining mass was not'required.
<br /> N 14.Assumptions, parameters, calculations and model used in risk Due to no groundwater contamination, a risk
<br /> assessments, and fate and transport modeling; assessment.was not required.
<br /> i15. Rationale why conditions remaining at site will not adversely Contaminated soils were removed and groundwater
<br /> impact water quality,.health, or other beneficial uses;and contamination was not identified.
<br /> By: Comments: The site is a fuel storage area for the Tracy Memorial Hospital Two diesel USTs(one 550-gallon and one
<br /> MH 5,000-gallon) were removed in September 1988. A third UST(1,000-gallon gasoline)was closed in place in
<br /> February 1990, and soil samples collected from two angle.borings, drilled underneath the"gasoline UST, were non-detect
<br /> for all constituents. The gasoline UST was given a `clean closure"certification, and no additional work was required. Soil
<br />! Date: contamination at the former diesel USTs was identified to fen feet. Multiple borings were completed, and contaminated
<br /> 2/21/02 soils were excavated and removed in January 1989. Soil and groundwater samples were not tested for MtBE, and the
<br /> County has determined that the diesel USTs were used for diesel only, and WE testing was not required. Considering
<br /> that the USTs were removed in 1988, MtBE was not in widespread use at this time. Based on the;site investigation and
<br /> excavation activities completed to date, Board staff.concur with San Joaquin County's closure recommendation.
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