A federal judge has approved an agreement between conservation groups and the U.S. Environmental Protection Agency to set pollution limits for Queen Creek.

That could impact the proposed Oak Flat Copper mine east of Phoenix.

The EPA sets water quality standards but turns day-to-day operations to the states.

Conservationists say the Arizona Department of Environmental Quality has failed to come up with a plan to clean up pollution in Queen Creek, which is located near Oak Flat.

Last year, a coalition of nonprofits filed suit to force the ADEQ to do so.

The state says its standards are already high, and that discharge from the mine may never even enter the streambed.

The agreement gives ADEQ about four years to come up with its own plan.