A chlor-alkali production plant was in operation at the site from the mid-1960s to late 1970s to support ore refining. Groundwater constituents include mercury and DNAPL constituents. A groundwater extraction and treatment system provides capture of contaminated low-salinity groundwater and draws in unimpacted saline water.
EHS Support designed a field sampling and monitoring campaign to address key hydrogeological and geochemistry questions, including the form of mercury and fate and transport of constituents under pumping and non-pumping conditions. Geochemical models were used to understand the effects of decades of operation that mixed different waters, and the effects of resulting mineralization on aquifer properties. Models were verified with measurement of aquifer hydrogeological properties and Monte Carlo simulations were completed to determine optimal extraction system configurations, necessary to meet objectives of the regulatory approved remedy.