ZVI-Clay remediation of a chlorinated solvent source zone, Skuldelev, Denmark: 2. Groundwater contaminant mass discharge reduction

► Source remediation (ZVI-Clay) impacted the down-gradient contaminant mass discharge. ► The contaminant mass discharge (PCE) decreased 76% over a 19-month period. ► Four distinct phases was observed for the contaminant mass discharge (PCE). ► A temporary increase and slow long-term reduction followed the initial reduction. ► Numerical modeling was utilized to identify the governing processes.