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- TA6w F_ 1 - CHECKLIST OF REQUIRED ATA
<br /> > FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> ` Site Name and Location: Mel Bokides Petroleum, 501 W. Lodi Avenue, Lodi, San Joaquin County
<br /> 1- Distance to production wells for municipal, domestic, agriculture, A 2003 sensitive receptor survey reported one
<br /> ' industry and other uses within 2000 feet of the site; municipal supply well located 1,100 feet to the
<br /> northwest.
<br /> 2. Site maps, to scale, of area impacted showing locations of former and existing tank Three 10,000-gallon gasoline
<br /> systems, excavation contours and sample locations, boring and monitoring well elevation US Ts were removed 2198.
<br /> contours,gradients, and nearby surface waters, buildings, streets, and subsurface utilities;
<br /> 0
<br /> 3. Figures depicting lithology(cross section), treatment system diagrams, Site lithology consists of sand,silt and clay.
<br /> The total depth investigated was 65 feet.
<br /> N 4. Stockpiled soil disposed off-site(quantity); An unspecified amount of soil was excavated and spread onsite.
<br /> D] 5. Monitoring wells remaining on-site, fate; Six monitoring wells(BMW-1 to B MW-5,MW-5), and the SVE/AS treatment
<br /> system installed for this investigation, will be properly abandoned.
<br /> 6. Tabulated results of all groundwater elevations and depths to water; The depth to water varied from 44 to 52 feet. The
<br /> groundwater flow direction varied from southeast
<br /> to southwest.
<br /> FY 1 7. Tabulated results of all sampling and analyses: Maximum soil boring results in 2/98 reported TPHg(13,600 mg/kg),
<br /> Y -De'tecficn 7i sTo`r confirmation sam !in - benzene25.mg/kg),-foluene_f,480-mg/kg),,-ethylbenzene_(-1-60-nag/kg);�
<br /> Y p g -{�
<br /> xylenes(1,200 mg/kg), and MtBE(<10 mg/kg): In 6/03, after SVE/AS
<br /> Lead analyses confirmation soil analyses reported TPHg(580 mg/kg), and TPHd
<br /> (800 mg/kg). Groundwater maximum results from 2199 reported TPHg
<br /> (85 mg/L), TPHd(6.8 mg/L), benzene(2,7 mg/L)toluene(10 mg/L),
<br /> ethylbenzene(160 mg/L),xylenes(1,200 mg/L)and MtBE(0.85 mg1L).
<br /> (390 ug/L). In 7/03, groundwater samples reported TPHg(1,7 mg/L),
<br /> TPHd(3.5 mg/L), toluene(0.018 mg/L), ethylbenzene(0:037 mg/L),
<br /> y xylenes(0.021 mg/L), and MtBE(0.014 mg/L).
<br /> 8. Concentration contours of contaminants found and those remaining in soil The extent of contamination is defined by
<br /> d groundwater, both on- and off-site: soil borings and groundwater monitoring
<br /> Y Lateral andVertical extent of soil contamination wells.
<br /> Y
<br /> Lateral and Vertical extent of groundwater contamination
<br /> 9. Zone of influence calculated and assumptions used for subsurface Based on the extent of soil and
<br /> remediation system and the zone of capture attained for the soil and groundwater contamination, an engineered
<br /> groundwater remediation system; remediation system(SVE/AS)was required
<br /> at this site.
<br /> 10.Reports/information 0 Unauthorized Release Form E] QMRs, 2198 to 10/03
<br /> 7l Boring logs PAR El FRP El Other CAP(2/98) Closure Report(10/03
<br /> 11.Best Available Technology(BAT) used or an explanation for not using BA T, Remove UST, SVE/AS and natural
<br /> attenuation. }
<br /> 12.Reasons why background waslis Minor soil and groundwater contamination remains on-site.
<br />,.... unattainable-using_BAX;-
<br /> 13.Mass balance calculation of substance Mass balance remaining was not estimated;2,326.5 gallons TPHg removed.
<br /> treated versus that remaining;
<br /> 0 14-Assumptions, parameters, calculations and model used in risk
<br /> assessments, and fate and transport modeling;and A risk assessment was not required.
<br /> 0 15. Rationale why conditions remaining at site will not adversely Soil and groundwater contamination is limited in extent,
<br /> impact water quality, health, or other beneficial uses. and based on 14 quarterly sampling events,
<br /> contamination is not leaching to groundwater.
<br /> By: Comments: Three 10,000-gallon gasoline USTs were removed 2/98. Multiple borings and six monitoring wells were
<br /> JLB completed to delineate contamination at this site. Maximum soil boring results in 2/98 reported TPHg(13;600 mg/kg),
<br /> benzene (<25 mg/kg), toluene (480 mg/kg), ethylbenzene(160 mg/kg), xylenes(1,200 mg/kg), and MtBE(<10 mg/kg). In
<br /> Date; 6103, after SVE/AS confirmation soil analyses reported TPHg(580 mg/kg), and TPHd(800 mg/kg). Groundwater
<br /> maximum results from 2/99,reported TPHg(85 mg/L), TPHd(6.8 mg/L), benzene (2,7 mg/L)toluene(10 mg/L),
<br /> 3/3/04 ethylbenzene (1 60 mg/L),xylenes(1,200 mg/L) and MtBE(0.85 mg/L). (390 ug/L). In 7/03, groundwater samples
<br /> reported TPHg(1.7 mg1L), TPHd(3.5 mg/L), toluene(0.018 mg/L), ethylbenzene (0.037 mg/L), xylenes(0.021 mg/L), and
<br /> MtBE(0.014 mg1L).. Based an the limited extent of soil and groundwater contamination, completion of corrective action
<br /> and two quarters of groundwater analysis, which show decreasing concentrations, Board staff concur with San Joaquin
<br /> County's Closure Recommendation.
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