NEWS

Globe and Mail - 6 July 2000 - The federal government is adopting a national standard to test toxic discharge from Canadian mines: Dump some of the discharge into an aquarium, typically add 10 rainbow trout and if half the fish survive after 96 hours, it's okay.

But it will not impose specific limits on the discharge of mercury and cadmium, two highly toxic substances, from mines across Canada as it redrafts its 23-year-old mine effluent regulations.

While the proposed regulations have come under attack from environmentalists, a federal official said that while not specifically addressing the presence of mercury and cadmium, those substances and others will be controlled indirectly by the new rules, and by new site-specific monitoring requirements.

The new LC-50 test (lethal concentration of 50 per cent) using the trout is the first time such a test has been used federally to measure what the government describes as a "non-acutely lethal effluent" being discharged directly from mines.

The idea is that a 50-per-cent survival rate in the discharged solution will be non-toxic to trout once the chemical cocktail is diluted in the streams and rivers where it is dumped.

The new standard is a component of the changes to the Metal Mining Liquid Effluent Regulations under Canada's Fisheries Act. The proposals do not take effect until they are published in the Canada Gazette later this year.

The changes to the 1977 regulations come after a seven-year consultation process between the mining industry, environmentalists, scientists and the federal government.

But not everyone is happy with the compromise made by the government.

The proposed regulations do not place restrictions on the allowable level of toxic elements such as mercury and cadmium, said Burkhard Mausberg, the executive director of the Canadian Environmental Defence Fund.

Although cyanide is being added to the list, the proposed limitations for arsenic, copper, lead, nickel and zinc will remain unchanged.

Mr. Mausberg said the standards being set for cyanide and lead are significantly higher than what consultants say can be achieved using the best available technology.

The weakness of the LC-50 test is that it does not address just how toxic the effluent is to a host of other fish species and organisms in the water, Mr. Mausberg said.

"The only sense that can be made of it is obviously the lobbying power of the mining industry and the Ministry of Natural Resources," said Mark Winfield, director of research for the Canadian Institute of Environmental Law and Policy. "It makes no sense from an environmental or human health perspective."

Even the fish test was a compromise. "That's an improvement, but we still don't have the water flea," said Brennain Lloyd, co-ordinator of Northwatch, a coalition of environmental groups in northeastern Ontario.

The proposed federal regulations do not require that the water flea, which is known as the daphnia magna in scientific circles, meet the survival test as is already required under Ontario's regulations. That standard test of toxicity was dropped by the federal government at the final meeting, she said.

The water flea and the trout live off different parts of the food chain. "They eat and are eaten by different things," Ms. Lloyd said. "It would not be extreme at all to expect to have two tests."

The government said the tests will be done on the water flea, but it will not be subject to the LC-50 standard.

But the federal government argues that the proposed changes to the regulations must be viewed as a package.

"We believe they are the most comprehensive and stringent mining effluent standards in the world, right now," said Patrick Finlay, chief of the minerals and metals division of the Environmental Protection Services of Environment Canada.

The new regulations propose that the allowable limits of total suspended solids be reduced to 15 milligrams a litre down from 25 milligrams.

Mr. Finlay said that by reducing suspended solids the amount of mercury and cadmium should also be reduced.

Over all, the proposed regulations put in place statistical limits on several chemicals, a biological toxicity test for fish and new regulations requiring mining companies to monitor environmental effects on the ecology, Mr. Finlay said.

"We can't specify everything that can be toxic," Mr. Finlay said. "In effect, we are regulating the toxicity and ecological impacts not only of mercury and cadmium, but a host of other substances many of them unknown and undefined. But that is the power of this regulation and [its] architecture."