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that the best soil remedial option for the subject site is soil vapor extraction (SVE) based on <br /> McLaren/Hart's past experiences with and the proven effectiveness of SVE <br /> SVE is an insitu method of removing organic vapors from the soil An SVE system utilizes <br /> vadose zone wells (wells constructed in the unsaturated zone) manifolded to a blower The <br /> blower creates a vacuum in the soil through the well which in turn will evacuate the volatile <br /> organic constituents such as gasoline and benzene The vacuum created in the soil pores will <br /> also initialize the volatilization of contaminants in the liquid phase The volatile compounds are <br /> drawn to the surface and passed into granulated activated carbon (GAC) vessels The GAC <br /> adsorbs the volatile compounds Prior to complete saturation of the GAC with volatile <br /> compounds it is changed out with fresh GAC <br /> McLaren/Hart proposes to include the soil vapor extraction pilot test as part of the feasibility <br /> study in order to have hard data available for the presentation of the remedial options to <br /> PHS/EHD The hard data collected during the pilot test will enable McLaren/Hart to perform <br /> the feasibility study more cost effectively and to focus the feasibility study on that remedial <br /> option which McLaren/Hart believes will provide the best technical solution for the site <br /> Task 1 - Soil Investigation <br /> Prior to any field work, the Site Health and Safety Plan previously prepared for the site, will <br /> be updated The Health and Safety Plan will include a task risk analysis and an emergency <br /> response plan The underground utilities at the subject site have been mapped to scale and kept <br /> on record in McLaren/Hart files, thus, a utility clearance will not be performed for this phase <br /> of work <br /> McLaren/Hart proposes that a total of eight soil borings be advanced to groundwater <br /> (approximately 26 feet below grade) adjacent to the source area and at the perimeter of the <br /> subject property, and a maximum of 25 soil samples be analyzed to fully define the lateral extent ! <br /> of petroleum hydrocarbon impacted soil In addition, the data will be used for the purpose of �G°/ <br /> designing the chosen remedial system <br /> The soil borings will be dnlled utilizing a mechanized, vehicle mounted soil probe system For <br /> those soil borings located within the source area, the soil samples will be collected continuously <br /> from 12 feet below grade to the saturated zone, and for those soil bonngs located outside the <br /> source area, the soil samples will be collected continuously beginning at 20 feet below grade to <br /> the saturated zone The soil samples will be field screened for volatile organic compounds <br /> (VOCs) using a photoinization (PID) Based on the PID readings and the discretion of the <br /> McLaren/Hart field supervisor, selected soil samples will be analyzed on-site by a state approved <br /> mobile laboratory unit McLaren/Hart anticipates a total of 25 soil samples will be analyzed <br /> Based on the analytical data acquired during the soil probe sampling event, the vadose zone well <br /> location will be determined <br /> Soil samples collected for mobile laboratory analysis will be immediately sealed with Teflon <br /> . sheeting and plastic end caps The end caps are then sealed to the brass tube with duct tape <br /> The samples are labelled, secured in a resealable plastic bag, and handed directly to the chemist <br /> in the mobile laboratory Soil samples will be analyzed for total petroleum hydrocarbons as <br /> o929[caz 3 <br />