ARCHIVED REPORTS XR0007816 - Laserfiche WebLink

Home Browse Search

i 1 07 July 2003 AGE-NC project No 95-0142 page 5 of 7 based on site-specific hy�'ogealagic conditions and hydrocarbon distribution of hl gh concentrations of dissolved'h drQe�bon distribution The limited areal MTBE, near the source of the release favors capturing cth and presence of the fuel additive hydrocarbons on the site A Bound water extracts e major j portion of the dissolved gradient portion of slgtilficantl impacted on system in the source area, along the down- impacted Y pacted ground water, should effectively address the plume of ' ground water and adsorbed contamination AGE recommended _ action work plan for the installation of additional water Ppreparation of a remedial 'UST area in order to increase 1)the effzcioncy-of perattiion of Xtractlon wells aro system and 2) the effectiveness of the wid the former ground water extract�osystemstabilztractiontreatment dissolved hydrocarbons and the adsorbed contarrii --r ext Gro conducted in conjunction with sol] vapor extraction tom Y t° address the ' and water extraction should be for more effective sol, vapor extraction maximize the thickness of the vadose zone In Final Remedlation Plan, dated June 19, 2002, AGE pro aces diameter ground water extraction wells along the eastern edpe es to install four additional, six-inch of the area of highest-known ground water contamination Based on the distributionure )ofh -gradient impacted ground water detected in samples from the monitoring wells on t the ground water extraction wells along the eastern edge of the proposes thatJoe (Figure 2) The extraction wells the ea screened he site AGE prposes that g eyard be located approximately20fcet Permeable zone(between 25 and 50 feet bs from 30 t° b0 feet big to address the more water g), which contained the most intensely impacted ground SITE CONTAMINATE MODEL Based on the data developed to date,including all soil burin s vapor<<a installed,AGE has developed a site subsurface m g sam lin the contaminants in the subsurface as described below for the release sampling and m° ism. g wells Iow >migration and distribution of • All sol' borings and well completion Iogs readily available Analytical data for soils, soil vapor and water samples, as wells a depicted in Appendix and analytical vaA ground water data are included in A s ground water elevation ' The subs_ui'face from site grade to approximately 80 feet bx B grained soil with acoarse-grained interval of variable thickness is composed primarily of fine- grained ne- between 25 and 40 feet bsg and laterally discontinue ess and lateral extent occurring approximately 75 to 80 feet bsose us coarse-grained interval at ' _ sIdiments Stratigraphzc cross sections are depleted on F site is composed of fine Figures 5 and 6 wined • Based upon soil samples submitted for geotechnical analysis,c'a encountered between 35`and SO feet b " Y y or clay with fin sg The cIayhad a permeability range of 1 X1 Q 6aem/secs Advanced GeoFnvaron,",,,l,Inc