Sludge from an isolated cove in Boat Harbour will be pumped into giant fabric-like tubes called geotubes for treatment when pilot work for the remediation of the water body begins.
Boat Harbour was once a tidal estuary before it was converted into an effluent treatment site.
Since 1967 it has been used as the site to treat and release effluent from Northern Pulp. Canso Chemicals also used the site to dispose of effluent between 1971 and 1992.
The geotubes will allow the water from the sludge to be removed and treated. The contaminated material remains with the tube, which will be relocated to a containment site already located near the Boat Harbour treatment facility. The treated water during the pilot phase will be released back into the cove.
Project lead for Nova Scotia Lands, Ken Swain, said they’ve chosen this method for the pilot work because it allows them to reduce about 70 per cent of the volume from the sludge by removing the water.
Construction for the pilot test site is now underway. From October to mid-January the sludge will be removed from the bottom of the cove, after which it will go through the treatment process.
In the last couple months three contracts have been awarded for the pilot work.
Trenton’s Balodis Inc. was awarded a contract valued at $768,000 (taxes in) to complete the infrastructure work for the pilot work. This includes a site where pumps will be set up to remove the sludge from the bottom of the cove as well as the treatment pad itself where the geotubes will be set up for the work.
Meanwhile, Sanexen Environmental Services Inc. was awarded a $4.8 million (taxes in) contract to physically remove the sludge from the test site and do the project work.
Swain said Sanexen was chosen because they demonstrated the best technical ability of removing the contaminated material from the bottom of the harbour.
From their preliminary work, he said they’ve discovered the contaminated material is on average about a foot thick and is sitting on top of the clean harbour bottom.
A primary concern, he said, is removing it without disturbing the clean bottom.
He said the containment site already at the Boat Harbour treatment facility has been inspected and is in good condition, although it will need to be refurbished and the height increased to handle the additional contaminated material. At the end of the project the site would be capped and then monitored.
Another contract worth $803,000 (taxes in) was awarded to Stantec Consulting Ltd. to conduct Independent Air Monitoring during the project. Swain said they will check the air quality now to use as a baseline and then monitor it throughout the project to see if there are any issues.
“They’re operating independently of any other kind of work.”
In addition to the sludge on the bottom of Boat Harbour, NS Lands will also have to deal with removing the pipeline to the treatment facility, the buildings on site and the removal of the dam which will return Boat Harbour to a tidal estuary.
Swain said the pipeline that goes from Northern Pulp to Boat Harbour will be abandoned and cleaned and removed in a number of places. The larger building on the site will probably be decommissioned and repurposed, he said.
The dam that was installed in the 1960s will be removed once the cleanup work is done and a bridge put in its place.
COST OF THE PROJECT
The exact cost of remediating Boat Harbour is still unknown, but the province has set aside $217 million for the project. Swain said the project has a class D estimate with the province of $200,000, which indicates a range in price from $140 million to $300 million.
“There are a few items that aren’t in that estimate that need to be added in,” Swain said.
Swain hopes they may be able to get some federal contributions to the project.
While there’s not been an official request yet, Central Nova MP Sean Fraser said he has spoken with Premier Stephen McNeil and Ken Swain about it.
“I think it’s important we take this kind of project seriously,” he said.
The federal government has money allocated for green infrastructure and a category within that is environmental remediation, which he said could possibly be used for this project.
He said he will personally be encouraging a federal contribution.
“I’m going to be on their side to help with the remediation of the site,” he said, noting its importance to Pictou Landing First Nations as well as people in Pictou County.
REALTED: Federal agency eyeing Boat Harbour remediation plans
