Barrhaven plant gets committee's OK, but contamination concerns linger

A city committee has agreed to rezone a former gravel pit to make way for a new manufacturing plant, but the decision has raised concerns about the potential for contamination from a nearby landfill.

The city's agriculture and rural affairs committee approved the rezoning without debate or discussion Thursday.

The former Drummond/Costellopit on Borrisokane Road is now owned by homebuilder Caivan Communities, which wants to constructa100,000-square-foot plant for manufacturing prefabricated house components. City staff saidthe plantwould create 250 jobs, and the componentsit produces could supply local builders, as well as those elsewhere in Canada and the United States.

The project can go ahead nowif Caivan drills a well and installs a septic system. But the developerwants the plant and a future office buildingconnected to the city's sewer and water system, somethingrural properties don't get except in rare circumstances.

It's also a potentially riskier option that city staff said needs further investigation.

Concern over leachate

Staff are concerned about the potential for contamination from the city's Trail Road Waste Facility, located 150 metres away across Highway 416. At the centre of their concern is something called aleachate plume contaminated groundwater that has seeped through the garbage and now sits under the dump.

For now, the leachate plume is contained under the Trail Road facility, and the city monitors it. But if Caivan is allowed to excavate to lay pipes deep in the ground, water that typicallyfills the excavated areamust be pumped out, a process known as "dewatering." That's when the problem can occur, staff say.

"Any pumping of groundwater that may occur east of the landfill could disrupt the existing groundwater flow regime and cause the plume to migrate offsite, under Highway 416 and into the development lands," wrote staff in their report.

Liability fears

That would be out of line with provincial environmentalrules, leaving the city legally liable for underground contamination of the surrounding lands, staff warned. The city could also be on the hook for the cost of any mitigation.

Staff have assessed the risk of that happening as "low to moderate." Just in case, the city hashired Dillon Consulting to predict how development east of Highway 416 could affect the landfill contaminants. Caivan has also agreed to produce a separate cost/benefit study.

Even though the committee approved the rezoning, Caivan's plan to connect to municipal pipes can't go ahead without further city approval.

Meanwhile, the Ministry of Natural Resources and Forestry has givenwritten confirmation that the aggregates licence for the former Drummond pit has been retired.

Part of the land will also be zoned for a pond to manage stormwater for the 500-home subdivision Caivan has had approved on the former Brazeau pit, immediately to the south.