ARCHIVED REPORTS XR0003450 - Laserfiche WebLink

Home Browse Search

Ms Marla Guensler Exxon Company, U S A August 25, 1995 Page 3 Quarterly ground water monitoring was performed at the site on July 14, 1995, three days before the completion of the air sparging:test Ground water samples were collected from all of the monitoring wells The concentrations of petroleum hydrocarbons constituents remained below laboratory detection limits in each of the observation wells (MW-1 and MW-4 through MW-6) The concentration of toluene, ethylbenzene, total xylenes, and TPH as gasoline for the sample collected from the test well (MW-3) on July 14, 1995, were below the laboratory detection limits The concentration of benzene in the ground water sample collected from MW-3 on July 14, 1995, was 15 µg/L Copies of laboratory analytical reports from March 31, 1995, and July 14, 1995, are included in Enclosure C The results of the extended air sparging test performed on monitoring well MW-3 indicate that air sparging did increase the DO content of the ground water in the sparge well and increased the soil vapor carbon dioxide which is indicative of biodegradation of petroleum hydrocarbon constituents Ground water sampling results also indicate that air sparging significantly reduced the concentrations of dissolve petroleum hydrocarbons in the ground water in the immediate vicinity of the sparging well Remarks The recommendations contained in this report represent our professional opinions, and are based m part, on information supplied by the client These opinions are based on currently available information and are arrived at in accordance with currently accepted hydrogeologic and engineering practices at this time and location Other than this, no warranty is implied or intended Delta recommends that a copy of this report be forwarded to Mr Michael J Infurna Environmental Health Division Public Health Services San Joaqum County Post Office Box 2009 Stockton, Califorma 95201