Laserfiche WebLink
Based on these sample results, PHS/EHD requested that an additional soil <br /> boring be advanced to delineate the total depth of soil and ground water <br />' impacts at the former tank location, such that the extent of all impacts at <br /> the former tank site would be defined Therefore, ERM installed one <br /> additional soil boring and one ground water HydroPunch at the former <br />' tank site on 11 February 1999 The results of this sampling event were <br /> presented in the Investigation Results Report Following this investigation, <br /> PHS/EHD concurred that the lateral and vertical extent of soil and <br />' ground water impacts at the former tank site had been defined <br /> 34 GROUND WATER REMEDIATION <br />' Following completion of the investigation activities,PHS/EHD asked <br /> Heinz to evaluate potential strategies for reducing the concentration of <br /> petroleum hydrocarbons in ground water An evaluation of potential <br />' remediation technologies for ground water was completed and presented <br /> in the Investigation Results Report As presented in that report, injection of <br /> ORC was selected as the best available technology for reducing ground <br /> water concentrations at the former tank site (Section 4 of this report <br /> presents the rationale for determining the best available technology for <br /> ground water remediation) <br /> ORC injection was performed at the former tank site during the week of 7 <br /> June 1999 ORC injection was performed at 20 locations downgradient of <br /> the former tank location Routine ground water monitoring (discussed <br /> below) was conducted every 2 months following ORC injection to track <br />' the reduction in petroleum hydrocarbon concentrations in ground water <br />' 35 GROUND WATER MONITORING <br />' Ground water monitoring has been performed at MW-2 since 1 May 1998 <br /> and at MW-5 and MW-6 since 16 November 1998 <br />' The concentration of petroleum hydrocarbons has decreased significantly <br /> at MW-2 since monitoring began During the 30 October 1999 and 6 <br />' January 2000 sampling events, TPH-g and BTEX were not detected in <br /> samples collected at this location Minor concentrations of TPH-g, <br /> ethylbenzene, and xylenes were detected during the most recent sampling <br /> event Based on the ground water samples collected at MW-2, it appears <br /> that as a result of ORC injection, enhanced bioremediation has reduced <br /> the concentration of chemicals at this location Table 8 presents the results <br />' FRM 14 HEINZ LSA 3374 60.3/27/00 <br />