Evaluation of freeze separation as a treatment for salt-contaminated groundwater

Groundwater contamination from road salt infiltration is a common problem at highway maintenance facilities. Freeze separation was investigated as a new application for the ex-situ remediation of groundwater contaminated by road salts. Freeze separation uses natural freezing temperatures to treat groundwater extracted from the contaminated zone, to produce ice and concentrated brine. The ice melts into treated water in the spring, and the brine is removed for off site disposal.; A literature review and demonstration project confirmed that freeze separation is an effective treatment of contaminated groundwater. The evaluation also resulted in: (1) a new method for calculation of concentrations in the ice and brine produced by freeze separation; (2) development of a mathematical model to predict the distance that contaminated water will flow across an ice surface during freeze separation; (3) a preliminary evaluation process to determine freeze separation viability; and (4) cost estimating criteria for future remediation projects.