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Optimization Evaluation, General Motors Former AC Rochester Facility, Sioux City, Iowa

The General Motors (GM) Former AC Rochester Facility (site) is located within the valley of the Missouri River in Sioux City, Iowa and is bounded by a steep loess bluff to the north, commercial properties to the east, and undeveloped properties to the south and west. A Sioux City municipal drinking water wellfield is located along the Missouri River southeast of the site. GM formerly used the site to assemble and test throttle-body injection fuel systems. Chemicals of potential concern (COPC) in soil and groundwater are chlorinated volatile organic compounds (CVOCs). CVOCs were encountered in soil and groundwater during Phase I and Phase Environmental Site Assessments (ESAs) conducted by GM at the site in 1993 after GM had ceased production at the site.

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