Pollution plume reaches New Mexico and Navajo Nation
FRISCO — The massive Aug. 5 spill into the Animas River from the Gold King Mine, near Silverton, has turned the river as acidic as black coffee just downstream of the spill site, the EPA reported after evaluating early water quality samples.
According to an EPA Region 9 Emergency Response web page, the spill was triggered when workers trying to clear debris accidentally damaged a makeshift berm that was containing polluted water.More info from the EPA page:
“The discharge has yet to cross the Navajo Nation boundary, near Hogback, but Navajo officials have reacted quickly, assessing their water intake systems and issuing a precautionary “do not use” public service announcement regarding tap water. Region 9 reached out to Navajo EPA officials and subsequently were requested assist w ambient river sampling in the San Juan River. The Navajo EPA surface water monitornig program (Shiprock Office) collected water and sediment samples from the San Juan River today – prior to the spill impact. NNEPA also requested drinking water sampling support immediately for Navajo operated water intakes. Region 9 deployed 2 START contractors to coordinate and assist them with sample collection and lab services and will assist in creating a sampling Task Force with NNEPA, Navajo water agencies and potentially the Bureau of Reclamation.”
The EPA is testing the river from near the mine all the way into New Mexico to try and assess the impacts from the spill, triggered by workers trying to address pollution at the site. Saturday morning, the agency released some preliminary information on Ph testing, similar to testing water in a swimming pool.
A more complete analysis to evaluate potential impacts from toxic heavy metal pollutants will take a little longer, as the samples have to be analyzed in a lab, while pH testing can be cone on the spot. Here’s what the EPA had to say about the pH sampling.
“pH (a measure of acidity) was measured at a number of locations along Cement Creek and the Animas River to Durango and beyond to Farmington, New Mexico. Except for locations within Cement Creek, generally, pH levels were measured before the arrival of the contaminant plume and found to range between 6.5 and 7.6.
When the contaminated water from the mine release passed a sampling location, the pH lowered (indicating more acid) to approximately 4.8 (below Silverton). A pH of 4.5 is consistent with the pH of a liquid like black coffee.
Later, however, in locations down river, the pH began to return to pre-incident levels. Water acidity levels in the Animas above Cement Creek have been consistent over the past two days at approximately 6.4 to 6.8. For reference, the pH of saliva is roughly 6 and the pH of pure water is 7. The acidity level in Cement Creek has remained low at 3.74 since the mine release. Tomato juice and apples also have a pH of approximately 3.74. While this reference information is relevant to skin exposure, the evaluation of impacts of these pH levels on fish and other aquatic life is ongoing.”
At the EPA’s on scene coordinator web page, the agency said it is rebuilding settling ponds near the mine portal to try and contain and treat lingering polluted flows from the portal with caustic soda and flocculent to lower the acidity once the ponds are built.
The EPA is also using aircraft mounted sensors and cameras to get data about the advance of the pollution plume downstream.
Environmental groups are also involved in monitoring the situation, including the locally based Animas Riverkeeper.
“We’re in the process of assessing what exactly we’re dealing with here,” said Aaron Kimple, Program Director, Mountain Studies Institute in Durango, Colorado and founder of Animas Riverkeeper. “As soon as we heard about the spill, we began sampling and testing for water quality and invertebrates and continue to take samples every two hours. We will be looking at both pre and post sampling results. We do know that the river is carrying a lot of sediment that can deposit heavy metals with the potential to create impacts years down the road.”
Lesley Adams, Western Regional Coordinator at Waterkeeper Alliance, added: “We, like many others, are concerned about the impacts of this tragedy on the Colorado River watershed. Water diversions, pollution and drought are taking a heavy toll on this epic river system. We encourage people at the local level to get involved and support the San Juan Citizens Alliance water program, so that this body of water has a voice and an army of advocates fighting for its future.”
Mountain Studies Institute and Waterkeeper Alliance are working to secure money for testing the samples collected. “Once the samples are analyzed and we know what we are dealing with we can identify ways to address any impacts” Kimple said.