Sludge creates disaster areas
ALBUQUERQUE, N.M. — Farmers, towns and tribes slammed water-intake gates shut as a sludge-laden plume from a Colorado mine spill rolled down principal rivers Monday in the desert Southwest, prompting concerns about possible long-term threats from heavy metals borne along by the spill.
Colorado and New Mexico declared stretches of the Animas and San Juan rivers to be disaster areas as the waste stream estimated to be 160 kilometres long churned downstream toward Lake Powell in Utah after the spill Wednesday at the abandoned Gold King mine.
The Navajo Nation, which covers parts of New Mexico, Utah and Arizona, declared 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 meeting Monday and echoed the sentiment of New Mexico officials that the federal government needs to be held accountable.
The 11.36 million litres of mine waste included high concentrations of arsenic, lead and other heavy metals. Workers with the U.S. Environmental Protection Agency accidentally unleashed the spill as federal and contract workers inspected the abandoned mine site near Silverton, Colo.
The EPA has said the contaminants were rolling too fast to be an immediate health threat. Experts and federal environmental officials say they expect the massive river system to dilute the heavy metals before they pose a longer-term threat.
Dissolved iron in the waste turned the long plume an alarming orange-yellow — a look familiar to old-time miners who call it “yellow boy” — so “the water appears worse esthetically than it actually is, in terms of health,” said Ron Cohen, a civil and environmental engineering professor at the Colorado School of Mines.
EPA officials said stretches of the rivers would be closed for drinking water, recreation and other uses at least through Aug. 17.
Tests show some of the metals have settled to the bottom and would dissolve only if conditions became acidic, which isn’t likely, Cohen said.
The best course for the EPA would be to leave the metals where they settle, he said, noting next spring’s mountain snowmelt would help dilute the contaminants further and flush them downstream.