The Harper government must report in a national public database all the pollution being produced by mining companies, a Federal Court judge ruled Thursday.

The National Pollutant Release Inventory (NPRI), created in 1993, details all the industrial and commercial pollutants released into the air, water and land in Canada.

Since 2006, NPRI has also required that all pollutants released during mining activities must be reported. Some of the waste found in tailings and waste rock — including mercury, sulphuric acid and arsenic — is deemed toxic by law and must be reported in the NPRI.

But due to the government's interpretation of the Canadian Environmental Protection Act (CEPA), the NPRI has not included the pollutants present in the tailings and waste rock produced during the extraction of ore.

In Thursday's ruling, Justice James Russell said the government "erred" in its interpretation of the law.

In his ruling, Russell wrote that "it is clearly unsatisfactory that such an important part of the pollution picture in Canada is not being reported to the public under CEPA."

Environment Minister Jim Prentice said the government will comply with the court's ruling.

Ecojustice, formerly known as the Sierra Legal Defence Fund, had filed suit against the government in 2007 on behalf of two environmental groups, Great Lakes United and Mining Watch Canada. The suit alleged the government broke the law by failing to collect the pollutant information and publish it in the NPRI.

Prentice and a consortium of mining companies had fought against publishing the information in the NPRI, but conceded that the public should know which chemicals are present in waste rock and tailings. Both groups called for the establishment for a separate database that would detail this information.

Their discussions to establish such a record had gone on for 16 years without yielding results, a pace Russell called "glacial." He said there "is still no clear indication from the minister as to how and when this important information is going to be gathered and provided to the Canadian public."

Ruling praised

Russell's ruling was praised by the two environmental groups that brought the suit.

"Canadians living in places like Sudbury, with mining operations in their backyards, were blindfolded while millions of kilograms of carcinogens and heavy metals accumulated in tailings ponds and waste rock piles across the country," John Jackson of Great Lakes United said in a statement.

"With this decision, the blindfold comes off and citizens can truly hold these companies to account for their pollution and the environmental and health dangers they pose."

But the executive director of the Chamber of Mineral Resources in Newfoundland and Labrador — which produces between 10 and 12 per cent of all of Canada's minerals — disagreed.

Gerry O'Connell told CBC News on Friday that tailings and waste rock are "not a major source of pollution. It's material that's simply removed in the process of mining to get at the ore. So waste rock could hardly be considered pollution. It would be same as a rock cut on the highway."

Jamie Kneen of Mining Watch Canada agreed that the material is naturally occurring, but said it is made hazardous after being brought to the surface and processed.

Metal mine tailings and waste rock accounted for 27 per cent of all pollutants produced in the United States in 2007, according to the Toxic Release Inventory, the U.S. equivalent of the NPRI.