This is an Administrative Order on Consent (AOC) between US EPA and the Navajo Tribal Utility Authority (NTUA) for violations of the Clean Water Act National Pollutant Discharge Elimination System (NPDES) permit at its Window Rock Wastewater Treatment Facility. This AOC directs NTUA to undertake specified measures to cease the current violations and prevent additional violations at this facility, and supersedes and replaces a previous AOC issued to NTUA for this facility in 2006.