HALIFAX, N.S. -- The environmental assessment process is officially underway for Northern Pulp's estimated $350-million plan to reopen its idled kraft pulp mill in Nova Scotia's Pictou County.

The provincial Environment Department formally registered the project Tuesday, for the more rigorous Class II environmental assessment, which typically takes 275 calendar days to complete.

Under the process, the department will release the terms of reference needed to properly assess the company's proposal on Dec. 21 -- a date that will also see the beginning of 30 days of public consultations that will include the Mi'kmaq community.

Public comments will be accepted until Jan. 31.

Mill owner Paper Excellence says its "transformation plan" would slash water use, reduce wastewater components, lower visible plumes from the mill's stacks and remove detectable odours during normal operations.

The plan would also see the mill discharge treated effluent into Pictou harbour, a move Pictou Mayor Jim Ryan has previously said there's "very little tolerance for" within his community.

The mill was mothballed in January 2020 after the province banned it from dumping effluent near the Pictou Landing Mi'kmaq community.

The company had submitted two plans that would have seen the mill dump wastewater directly into the Northumberland Strait, but the province rejected both options in December 2019.

"The proposed mill transformation project has been developed in response to community concerns," the company says in its registration document.

The document says treated effluent will be discharged into the Pictou harbour estuary from the mill's location in Abercrombie Point, although the exact discharge point will be determined through a study that will be part of the environmental assessment and engineering design process.

It says a large spill basin will also be built to provide a buffer between the mill and the effluent treatment facility in the case of a spill. It will be able to contain 20 hours of mill effluent and will be kept empty during normal operation of the mill.

The company also says approximately 40 per cent of the project's capital spending will deal directly with odour and air quality improvements, which will see an 80 per cent reduction in sulphur emissions from an average of 65 tonnes per year in 2019 to an estimated 13 tonnes per year.

It also says there will be a nine per cent reduction in greenhouse gases emitted by the mill's stacks from 55,500 tonnes per year to an estimated 51,000 tonnes.

Paper Excellence says construction of the project is expected to begin in late 2024 following environmental approval. It says the project will create 600 jobs and will take an estimated two years to complete.

This report by The Canadian Press was first published Dec. 7, 2021.