The water treatment plan by Teck Resources Ltd. would control selenium and nitrate that have been dumped into nearby rivers and streams as the mining giant expanded operations over the years.
The company will construct water diversions and treatment facilities at several of its mine sites, including at Line Creek, Fording River and Elkview Operations, the government said.
Environment Minister Mary Polak said Tuesday that the measures will improve water quality.
"This plan represents the next step in the long-term plan to ensure a healthy watershed in the Elk Valley," she said in a statement. "Many different groups have come together to find solutions."
In April 2013, the government ordered Teck Resources to stabilize and reverse water-quality concentrations. It cited the presence of several chemicals, including selenium, cadmium, nitrate, sulphate and the formation of calcite in the water.
The plan covers the entire Elk Valley watershed in the province's southeast and was developed with input from the Ktunaxa Nation Council and Montana-based experts, as well as regional and federal governments.
Ktunaxa Nation chairwoman Kathryn Teneese said the plan provides an important foundation for dealing with critical water-quality issues in the Elk Valley watershed.
Last December, a Washington state judge ruled that Teck is liable for the costs of cleaning up contaminants in the Columbia River from decades of dumping slag and effluent from the company's operations in Trail, B.C.
Judge Lonny Suko found Teck knowingly discharged waste downstream for decades, noting the company admitted treating the international waterway as a free waste disposal service.
Almost 10 million tons of slag, including heavy metals such as lead, mercury and arsenic, was leeched between 1930 and 1995, Suko said.
Vancouver-based Teck Resources owns and has interest in 13 mines in Canada, the United States, Chile and Peru.