Approximately 5,400 m3 of soil contaminated with historic low-level radioactive waste in pond sediment and the north slope of the ravine
Resulted from contaminated groundwater (leachate) running downhill from the Highland Drive Landfill site, under Highland Drive, to the ravine and ponds
Remediation/Restoration Plans
Dredge the ponds
Install Permeable Reactive Barriers (PRBs), i.e. trenches filled with iron filings that bind with and trap contaminants as leachate passes through, to intercept contaminated groundwater before it reaches the ponds
Monitor groundwater upstream and downstream of the PRBs, replacing as necessary until the groundwater is clean
Transport waste by truck along the North Transportation Route to the long-term waste management facility
Restore ponds and restore/landscape ravine slopes
Special Considerations
Clearing of the site outside of fish spawning time (early September to mid-June) for areas around Highland Drive Creek and outside of nesting times for treed areas (March to July)
In addition to removing contaminated soil and sediment in Highland Drive South Ravine, long-term management of ongoing groundwater seepage and precipitation of contaminants is required
