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Mining and Water Pollution

There has been a barrage of harsh, even nasty, criticism directed at the EPA recently over the August 5 spill of three million gallons of polluted water from the Gold King Mine into the Animas and San Juan rivers. Members of Governor Martinez’s administration have been among the most vocal critics. One administration official remarked in the aftermath, “We’re taking this like our lives depend on it, because our lives do depend on this water. EPA is not taking this situation like their lives depend on the water.” In September, the same official testified before the House Government Oversight Committee denouncing EPA for not promptly making water quality data available to the State, a charge that EPA denied.
Clearly EPA made a serious and lamentable mistake in releasing the tainted water. The release had a destructive effect on the Animas River, and a devastating economic effect on many individuals and businesses that rely on the river for recreation, irrigation, and drinking water, in Colorado, New Mexico, and the Navajo Nation. The slug of polluted water, known as “acid mine drainage,” contained iron disulfide (pyrite) – which gave the water its unnatural yellow-orange color – sulfates, and sulfuric acid, and elevated levels of dissolved metals, including aluminum, arsenic, cadmium, chromium, copper, and lead. All these metals are to varying degrees toxic to humans and fish. Yet amid all the EPA bashing, there are several important facts to consider.
First, the source of the pollution was an old abandoned mine, not the EPA. The release originated from the unreclaimed workings of the Gold King Mine near Silverton, Colorado. The mine operated almost continuously from 1887 to 1922. The mine has remained inactive since then, leaving behind a legacy of pulverized waste rock laden with sulfates and heavy metals, and a continuous production of acid mine drainage.
Second, the Gold King Mine has been leaking acid mine drainage for decades. Prior to the August release, EPA estimates that the mine, together with other nearby abandoned mines, were releasing approximately 330 million gallons of contaminated mine water each year into Cement Creek, a tributary to the Animas. The release occurred when, as water accumulating in an old mine adit (horizontal tunnel) built up pressure on an earthen dam.
Third, EPA had attempted comprehensive cleanup of the site in 2008, but retreated in response to local opposition. EPA investigated the site for possible listing on the Superfund priority list, which would have provided substantial sums of cleanup money for comprehensive remediation. But EPA halted the listing process in deference to business and community leaders around Durango who feared that Superfund listing would diminish property values and discourage tourism.
The Governor’s posturing as an environmental watchdog rings particularly hollow given the administrative assault she has launched on New Mexico’s environment. Consider the recent Copper Mine Rule. The rule was drafted, proposed, and promoted by Martinez appointees at the Environment Department (with some ghost writing by the mining industry), over the futile objections of career department staff. It was adopted with little debate by Martinez appointees on the Water Quality Control Commission. And it has been defended – with the taxpayers paying the bill – by a private law firm the Martinez administration hired for the task.
Copper mines generate large quantities of acid mine drainage, precisely the sort of pollution released into the Animas River. At the Tyrone Mine in Grant County, for example, copper mining has polluted what was once high-quality groundwater. At some locations, levels of certain metals have exceeded state groundwater quality standards by as much as 1,000 times.
The Copper Mine Rule legalizes contamination of New Mexico’s precious groundwater with acid mine drainage. It allows copper mines to pollute groundwater within a “drainage area” around a mine – in effect a groundwater sacrifice zone. Within this area, no pollution control system, no monitoring or reporting of groundwater quality, and no cleanup of groundwater contamination is required. At the Tyrone mine, the area covers nine square miles.
The hopeful thinking behind the “drainage area” concept is that any polluted water will flow into open mine pits where it can be pumped out and treated. The contamination will be, on a vast scale, contained within the sacrifice zone. That is the theory of the Copper Mine Rule. But in reality, experience has shown that water containment systems are notoriously prone to failure. In the complex geology underlying large copper mines, faults, fractures, alluvial channels, and other preferential pathways can cause water to move in unpredictable and unexpected ways. Water, carrying its load of pollutants, most often finds a way to escape a containment system. This scenario has happened before at the Tyrone Mine. And, indeed, it was the breach of a poorly understood containment system that precipitated the Gold King Mine spill.
This absence of any requirements to protect or clean up groundwater is a stark and striking departure from past regulatory practice dating back decades. It also contravenes the New Mexico Water Quality Act. Enacted in 1973, the purpose of that statute is to prevent and abate water pollution. That law strictly limits the discharge of contaminants into any groundwater that has a present or potential future use. If a discharge would cause groundwater pollution levels to rise above the legal threshold, that discharge is unlawful.
To his credit, Attorney General Balderas has challenged the Copper Mine Rule in the courts. The New Mexico Supreme Court this summer agreed to hear the case; briefing is to be completed in December. Hopefully the high court – mindful of the calamitous Animas River spill – will recognize the danger in allowing similar mine pollution to foul the state’s invaluable groundwater resources.
Ben Shelton is the Political and Legislative Director of Conservation Voters New Mexico, a statewide nonpartisan, nonprofit organization working to connect New Mexicans to their political power to protect our air, land, and water for a healthy Land of Enchantment by mobilizing voters, helping candidates win elections, holding elected officials accountable, and advancing responsible public policies.