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maintain compliance with any implementation permits, and to evaluate progress toward attain- ing the remedial objectives Also, monitoring will be used as a tool to manage the dissolved hydrocarbon plume and to momtor and document the presence of VOCs in groundwater beneath the site Institutional controls will be used to reduce the possibility of exposure to petroleum hydro- carbon-affected groundwater at, or from, the site Generally, this is accomplished by restrict- ing access Currently, access to hydrocarbon-affected groundwater is controlled by sampling protocol and general plume location Since impacted groundwater will persist for some time during remediation, use will be restricted by prohibiting installation of drinking water wells at, or near, the site Additionally, groundwater pumping that may draw affected groundwater away from the site will be restricted 5.3.2 Alternative 2: SVE/Air Sparging with Treatment In addition to groundwater monitoring and institutional controls and plume definition, this alternative includes (1) design and installation of SVE and sparge systems, designs would utilize existing wells when possible, and (2) subsurface infection of compounds found to be limiting bioreclamation (other than introduced by SVE and spargmg) This alternative would include additional design and abatement due to the presence of the VOCs which occur beneath the site Application of this alternative would require installation of a SVE system and integral sparge system Given the thickness of the capillary fringe soils, the SVE well field would be installed utilizing vadose wells screened in hydrocarbon impacted areas Sparge points, equipped with approximately 2 feet of screen, would be installed so that the top of the screened section would be approximately 5 feet below the average groundwater surface Operation of the sparge system, with respect to active sparge points and sparge duration, would be modified in order to optimize volatilization and biodegradation 5.4 Alternative Evaluation Technical, institutional, environmental safety, and economic criteria were used to evaluate the alternatives Because some remedial alternative elements were common to both alternatives (i e , complete downgradient plume definition), only the characteristic elements were consid- ered during the evaluation process It was determined that Alternative 1 is the most feasible for long-term application An assumption of this selection is that the extent of dissolved hydrocarbons downgradient of the site is minimal due to the limited nature of the release and the relatively low concentrations of dissolves detected on site In the case that plume delinea- tion uncovers conditions which would require additional evaluation regarding remediation an addendum to this CAP would be prepared 3201357B1CAP 12 April 4, 1995