Colorado mine spill spews metallic discharge into waterways

Colorado Gov. John Hickenlooper has declared a state of disaster emergency after more than 11.3 million litres of potentially toxic wastewater from a defunct Colorado gold mine was accidentally released into local streams.

On Monday, New Mexico also announced stretches of the Animas and San Juan rivers to be disaster areas as the orange-coloured waste stream estimated to be 160 kilometres long churned downstream toward Lake Powell in Utah after the spill began Wednesday at the abandoned Gold King mine.

• Kayaker winds up in yellow wastewater

New Mexico Gov. Susana Martinez, who toured the region over the weekend, said she was heartbroken and called the spill a catastrophe.

"It's absolutely devastating," she said.

The Navajo Nation, which covers parts of New Mexico, Utah and Arizona, also claimed the spill to be an emergency as it shut down water intake systems and stopped diverting water from the San Juan River.

Members of the tribal council were frustrated during a special meeting Monday and echoed the sentiment of New Mexico officials that the federal government needs to be held accountable.

Hickenlooper said the order would free up some $500,000 US from a state fund for response efforts to the spill, which was inadvertently triggered last week by a team of Environmental Protection Agency (EPA) workers.

The discharge, containing high concentrations of heavy metals such as arsenic, mercury and lead, was continuing to flow at the rate of 1,900 litres per minute as of Sunday.

An unspecified number of residents living downstream of the spill — who draw their drinking supplies from their private wells — have reported water discolouration, but there has been no immediate evidence of harm to human health, livestock or wildlife, according to EPA officials.

Residents have been advised to avoid drinking or bathing in water drawn from wells in the vicinity, and the government was arranging to supply clean water to homes and businesses in need.

"We will work closely with the EPA to continue to measure water quality as it returns to normal, but also to work together to assess other mines throughout the state to make sure this doesn't happen again," Hickenlooper said in a written statement released by his office.

The Colorado Department of Public Health and Environment was testing downstream water quality and wildlife officials are assessing the impacts on fish and other aquatic animals, the governor said.

Last Wednesday, an EPA inspection team was called to the abandoned mine near the town of Silverton, Colo., to examine and clean up previously existing wastewater seepage. Workers instead accidentally released the mine waste into Cement Creek, a waterway that flows into the Animas River.

By Friday, the main plume of the spill had travelled 120 kilometres south to the New Mexico border, prompting local towns to shut off their water intakes from the Animas River, one of the main waterways affected, local authorities said.

Agency officials said they were consulting with representatives of the Navajo Nation.

In recent days, the EPA has been diverting the ongoing release into two newly built settling ponds where the waste was being treated with chemicals to lower its acidity and to filter out dissolved solids before being discharged to Cement Creek.

The creek's water quality has already been badly degraded from a long history of acid mine drainage in the area, agency officials said.