HALIFAX -- Opposition is mounting against a plan by a kraft pulp mill in Nova Scotia to pump treated waste into the Northumberland Strait, with a group of Maritime fisheries organizations saying the effluent could harm marine life.

The group, which includes the Pictou Landing First Nation in Nova Scotia, said the proposal from Northern Pulp Nova Scotia Corp. could see the release of up to 90 million litres of effluent per day into the strait, posing a threat to fish species and protected areas along the coastline.

The other members of the group include the Gulf Nova Scotia Fleet Planning Board, the Maritime Fishermen's Union, the Prince Edward Island Fishermen's Association and the New Brunswick Fisheries Association.

Under provincial legislation, Northern Pulp has until 2020 to replace its current effluent treatment plant in Boat Harbour near Pictou, N.S. -- a deadline the company has said will be tough to meet.

The group said other options should be explored, such as a land-based effluent treatment facility. They said rigorous scientific research is needed to assess the impact.

"The provincial government is asking us to take 100 per cent of the risk. Our concern is what is in the effluent. What's going to do to our fishery? What's the construction of the pipe going to do to our fishery?" said Ron Heighton, president of the Gulf Nova Scotia Fleet Planning Board.

Local fishermen, Nova Scotia Mi'kmaq chiefs and Prince Edward Island Premier Wade MacLauchlan are among those who have voiced concerns about Northern Pulp's plan, saying it could have unintended consequences for fisheries in the area.

Kathy Cloutier, spokeswoman for Paper Excellence Canada, which owns Northern Pulp, said in an email statement that effluent has been flowing into the strait for 50 years, and the proposed drainage site is not far from the current one.

"The new system will make it so that the treated effluent, in part due to planned in-mill improvements, will be of better quality with a smaller environmental footprint than what is currently in place," Cloutier said.

She said the company investigated its treatment options and determined it needed a drainage point to pump waste.

"The bottom line is no pipe equals no mill," she said.

Cloutier added: "Scientific studies are being completed with rigour, and First Nations, community and stakeholder engagement is occurring throughout the study."

The mill in Abercrombie, N.S., announced plans for a new treatment plant in December and is to submit an environmental assessment to Nova Scotia's Environment Department in July.

According to the company's plan, waste would be treated at a new facility near the mill using a system that would meet all federal environmental standards.

The effluent would be carried by polyethylene pipe across Pictou Harbour and then released through six pipes into the strait.

Nova Scotia's deputy environment minister Frances Martin faced questions about the plan at a public accounts committee meeting last month. She said she made the decision to go with a Class 1 environmental assessment last June after Northern Pulp filed a project description with the department at the end of April.

She said it was clear to her the project required a Class 1 assessment instead of the more lengthy Class 2 under provincial regulations. Martin said Class 2 assessments are used in cases of larger projects, such as the building of a petro-chemical plant or pulp mill.

But Heighton said he would like to see a federal environmental assessment.

"We need every bit of science so we can understand what's going on," said Heighton. "We cannot accept anything less."

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