HALIFAX -- The fate of thousands of jobs in Nova Scotia's forestry sector remains uncertain after the province's environment minister chose to withhold approval of a pulp mill's controversial proposal to pump 85 million litres of treated effluent daily into the Northumberland Strait.

Gordon Wilson said the province doesn't have enough information to determine if Northern Pulp's project will harm the environment, and the company can't move forward until it files a full environmental assessment report.

The minister said the new information is required to properly assess the company's plans for a new effluent treatment plant and a 15-kilometre pipeline near Pictou, N.S., which have met with stiff opposition from the Pictou Landing First Nation, environmental groups and fishermen from across the Maritimes.

"While there has been some good work done here, I have concluded that I need more science-based evidence, more information before me to properly assess the potential risks to air, water, fish and human health," Wilson told a news conference Tuesday.

"I am aware of the implications this could have on people's lives and livelihoods ... (But) I can't approve this project unless and until I feel confident that the science behind it supports it."

The mill, which directly employs 300 people, supports more than 2,000 additional jobs in the province's forestry sector, the company says. Unifor, which represents more than 200 workers at the mill, says the operation supports about 11,000 jobs across all sectors in the province.

It remains unclear what will happen to the mill, because it is facing a legislated deadline to stop dumping its effluent into lagoons at Boat Harbour near Pictou Landing by Jan. 31. The company has said it will close the mill unless the provincial government grants an extension to the deadline mandated under the 2015 Boat Harbour Act.

The chief executive of Northern Pulp's parent company, Paper Excellence Canada, issued a statement expressing disappointment in the minister's response Tuesday and calling for a decision "as soon as possible" on allowing the pumping of effluent into Boat Harbour to continue.

"Until we have a decision on the extension of the Boat Harbour Act, the future of Northern Pulp and Nova Scotia's forestry sector remain in jeopardy," Brian Baarda said.

Chief Andrea Paul, the leader of Pictou Landing First Nation, said her band of about 450 people agree with the department's view that the environmental assessment was incomplete.

"The minister didn't have enough information to outright deny the project, so I'm satisfied he (Wilson) has asked for a full environmental assessment," she said.

"It was probably the best we could have hoped for."

However, Jerry Dias, the national president of Unifor, said the approximately 350 workers at the mill are deeply concerned by the minister's decision.

He said during an interview in Halifax they are anxiously hoping the premier alters legislation and permits Northern Pulp to continue sending effluent into Boat Harbour.

He urged the premier to extend the existing deadline, despite (Stephen) McNeil's previous commitment to Pictou Landing First Nation not to do so.

"You're going to have 2,700 less workers overnight. That's the impact overnight. That would be very irresponsible for any premier," said the union leader.

He was referring both to the workers directly employed at the mill, as well as the indirect jobs that could be lost in the forestry industries that supply the mill.

Friends of the Northumberland Strait, a coalition opposed to the pipeline, said in a news release it is "relieved and pleased" the plan was not approved, noting the company had five years to prepare its submissions.

"The minister ... recognized that Northern Pulp has not provided the science to show that this project can be built and operated without significant harm," said James Gunvaldsen Klaassen, a lawyer with Ecojustice, which is part of the group.

Jamie Simpson, a lawyer who represents three fishermen's groups, said in an interview that the question of the Jan. 31 deadline is the "elephant in the room."

Wilson declined to speculate on the possibility of an extension, saying the issue wasn't within his purview.

"My complete focus has been on this environmental assessment application from the very start," he said. "The Boat Harbour Act is not really in my jurisdiction ... I'm not going to speculate on something that is outside my responsibilities."

A spokesman in McNeil's office later said the premier would address the situation on Wednesday.

Wilson also declined to say what he would do if Northern Pulp continued to dump treated effluent into Boat Harbour after Jan. 31, in violation of the act. However, he confirmed that Northern Pulp has already applied for a new industrial approval that seeks to extend the company's use of the lagoons.

The Environment Department has up to 14 days to prepare and publicly release the terms of reference, and Northern Pulp has up to two years to submit a report. After that, study of the document can take up to 285 days.

- With files by Michael Tutton and Michael MacDonald in Halifax

This report by The Canadian Press was first published Dec. 17, 2019.