The state Environment Department said Tuesday the rules it has proposed would be the most stringent of any copper producing state in the West, including Arizona, Nevada and Utah. They include new engineering requirements for handling left-over rock, leach piles, tanks and pipelines.
"This idea that we've somehow lowered our standards or created a safe haven for polluters is completely untrue," said Ryan Flynn, general counsel for the department. "We've actually raised the bar."
The proposed rules have the support of New Mexico's copper mining industry, but environmentalists argue that the state stands to take a step back if the rules are approved by the state's Water Quality Control Commission.
Environmentalists accuse the department of giving in to the industry despite months of stakeholder meetings. Attorney General Gary King has also come out in opposition, saying the proposed rules would violate state water protection laws.
"For 35 years, the law of the land in New Mexico has been you protect groundwater quality. Now, what will be happening is mining companies get to use groundwater as essentially a dumping ground. They don't have to prevent pollution," said Allyson Siwik of the Silver City-based Gila Resources Information Project.
The water commission on Tuesday began what is expected to be a monthlong hearing. A final decision isn't likely until the summer, and experts say legal action will likely follow.
The proposed rules stem from legislation approved in 2009 that sought more consistent rules for regulating groundwater affected by copper mining. Last year, mining representatives, state environment officials and environmental groups attended nearly two dozen meetings to discuss the rules and the department hired an independent contractor to develop a draft.
Flynn said most of the contractor's proposal was adopted, but environmentalists argue that the final version submitted to the water commission includes most of the comments that were submitted by mining giant Freeport McMoRan, which operates several copper mines in New Mexico and Arizona.
Critics of the proposed rules say earlier versions required liners to be installed in certain areas. Under the version being considered by the commission, liners would be required at the discretion of the department when it considers granting permits or renewing permits.
Brian Shields, executive director of the watchdog group Amigos Bravos, said the proposal would allow for pollution of groundwater under a mining site as long as it doesn't spread.
"When was the last time we were able to contain a plume of pollution? It's just a step in the wrong direction, and it's contrary to law," Shields said.
Past court rulings have called into question the ability of the Environment Department to require water under mining operations to meet drinkable standards, Flynn said. Currently, companies can request variances under the state Water Quality Act to discharge pollutants and the department sets guidelines to ensure that public health isn't compromised.
The process allows for public comment, but Flynn said without a change in the rules, litigation will result every time a mining operation seeks a permit. He said the goal is to have clear and consistent expectations for mining companies.
Flynn acknowledged the environmental impacts of mining as well as the importance of protecting groundwater in such an arid state.
"We want to try to strike the right balance between the environmental and economic impacts of mining in the state," he said.