Over three million gallons of waste water, containing heavy metals such as arsenic, mercury and lead, gushed out of a disused mine and downstream into the Animas River after the accident last Wednesday, turning it bright yellow.
The spill was triggered by a crew working for the Environmental Protection Agency (EPA) at the Gold King Mine near Silverton in Colorado. The mine closed in 1923.
EPA boss Gina McCarthy said it was “a tragic and unfortunate accident and EPA is taking reponsibility to ensure that it’s cleaned up.”
The discharge continued to flow out at a rate of 1,900 litres a minute, forcing both the Animas and San Juan to be closed to drinking water and irrigation intakes. High levels of cadmium in the polluted water could be particularly problematic if it was used to irrigate crops.
Russell Begaye, the President of the Navajo Nation (above), declared a state of emergency and called for funds from the US federal government to help with the clean- up.
Mr Begaye said he intended to take legal action, telling a packed public meeting: “The EPA was right in the middle of the disaster and we intend to make sure the Navajo Nation recovers every dollar it spends clearing up this mess and every dollar it loses as a result of injuries to our precious Navajo natural resources.”
Mr Begaye demanded full disclosure of which chemicals had been released into the rivers: “We understand clean up will take decades. We demand clean up of this water and the sediments of our affected rivers immediately.”