Environment Secretary Ryan Flynn on Wednesday told members of a state legislative committee that the agency plans to monitor water quality for one year to ensure it's safe for recreational use.
Flynn said the agency instead needs to treat the incident as a human health issue.
New Mexico announced last month it intends to sue the EPA, the state of Colorado and the owners of two Colorado mines over the Aug. 5 spill. The EPA claims a contractor accidentally unleashed more than 3 million gallons of contaminated water during a cleanup project.
The EPA did not immediately respond to Flynn's criticisms.
