8/19/1997 BOARD OF SELECTMEN Minutes

Home Browse Search

is anticipated that roe access is Construction and operation would cause moderate nology, it P property Y erha s difficult. socioeconomic impacts on the residential neigh - pssible,though perhaps borhood near Ashumet Pond. Manageable risks to human health are anticipated in construction and operation of the system. Cost: Total capital cost is estimated to be $47.0 during Treatmentplants lants would be -located on base, thus million. Annual operating and maintenance cost is minimizing' izin potential risks to the off-base neighbor- estimated to be $4.0 million. Life-cycle cost, hood. including capital cost, based on 20 years of opera- Adverse impacts to rare species, to rare species tion (for cost-estimating purposes only) is estimated to be$127 million. habitats,to a coastal plain pond community, and to a wetlands complex expected, but can be miti- Public Acceptance: The public acceptance of all p are ed with a moderate level of scheduling and the response alternatives will be determined gat . action planning. However, the impacts throughout the public comment period. The respec�- can str p g construction aloe the Ashumet tive organizations, agencies, and community groups associated with g g. Pond shoreline would be less for recirculating well (acceptance groups)will review the information and technology .than for ETR. indicate a preferred choice, acceptable second and third choices, and any unacceptable alternatives. CSm10 PLUME RESPONSE ALTERNATIVE G Alternative ative C is the No-Action Alternative. It Hydrological and ecological thresholds are met involves leaving the site in its resent condition because there is no construction. Likewise, there is g P without an remediation system. No further no impact on species or habitats. Y y activities. would be conducted to comply with the This alternative fails the threshold criteria. EPA or DEQ' groundwater standards at the site. No er it has been carried through the evaluation . � However, g institutional controls would be instituted to prevent process in order to allow comparison with other exposure to contaminants. alternatives. Some groundwater monitoring would be performed Compliance with Applicable or Relevant and ' five-year review. This P in order to. complete a y Appropriate Requirements (ARARs): This alter- review, required by federal regulation, would be natiVe does not comply with the IROD which conducted to determine if there are any impacts to requires containment of the CS-10 plume. public health or the env five environment f years after q implementation of the alternative. Effectiveness and Permanence of Response Alter- natives: The table on page 3 summarizes plume The no-action alternative is developed for each capture by mass for all alternatives. A similar table Su impacts on human health p perfund site to assess p summarizing plume capture by volume is included in and the environment if no measures are taken to the matrix document. address current conditions. It also serves as a benchmark for comparison. to other cleanup alter- by Alternative fir, no contaminants are captured rP natives beingconsidered., The no-action alternative by active systems. Approximately 61 percent of the n is selected onlyat sites that pose little or no risk to total contaminant mass would be caught in silts and hum . For CS-14 the the remainder would continue to migrate an health-and the environment no-actio not provide adequate downgradient in the coarser, more permeable sands. n alternative would p q protection f health and the environment, This alternative does not remove contaminants. It p o human hea s Included for comparison Therefore,�t• purposes does not affect other plumes. A relatively large � only. percentage (39 percent) of the plume contaminants would continue to migrate downgradient of the Matrix Criteria current footprint; however, human health and Overall Protection of Human Health and the ecological risk factors associated with that portion Environmen • ' e contains no are low. Environment: This alternatxv provi- sion for eliminating or reducing exposure pathways. Socioeconomic impacts associated with the uncaptured portion of the plume, such as impacts on 13