SPOKANE — A deal has been reached that will allow a lead-and-zinc mine to continue to operate in Pend Oreille County, the state Department of Ecology said yesterday.

The agency, mine operator Teck Cominco American and three environmental groups settled their differences over a wastewater-discharge permit for the mine.

"This settlement is the result of open and constructive dialogue among all the parties and represents better environmental protection at the mine," said Jim Bellatty, who manages Ecology's water-quality office in Spokane.

"Teck Cominco greatly appreciates the hard work and sincere efforts by all the parties to resolve this appeal," said Dave Godlewski, environmental manager for Teck Cominco.

Ecology will inspect the mine four times a year to make sure it is complying with all environmental requirements.

The underground mine is north of Metaline Falls, Pend Oreille County, near the Canadian border. It reopened in January 2004 after being closed since 1977. Wastewater from the mine is treated and pumped into the Pend Oreille River.

The Ecology Department issued a wastewater permit in April 2004, but the Okanogan Highlands Alliance, the Washington Public Interest Research Group and The Lands Council appealed to the Pollution Control Hearings Board, saying the permit violated the Clean Water Act.

The original permit set limits on the amount of pollutants the mine's wastewater could contain and included requirements for monitoring effluent and reporting spills. The new settlement adds more restrictions on the temperature of the water to help the Pend Oreille River remain cool enough for fish.

"We are gratified that the good faith of all the parties could provide a basis for minimizing harm to the environment," said Mike Petersen of The Lands Council, a Spokane-based group.

Godlewski said about 500,000 gallons of groundwater that seep into the mine are treated daily.

Teck Cominco bought the mine in 1995 and spent more than $70 million to reopen it. The mine reopened in January under an extension of the original permit.

Ore from the mine is trucked to Cominco's smelter in Trail, B.C. Teck Cominco and the U.S. Environmental Protection Agency are battling over heavy-metals pollution in the Columbia River that flows from the smelter into Washington state.