The City of Toppenish operates a municipal wastewater treatment facility (Facility) that provides secondary treatment. The Facility receives domestic wastewater from residential and commercial sources. The Facility is located within the Yakama Indian Reservation but is not tribally owned. During the period from June 2008 to May 2010, the city has had 1,806 effluent limit violations of its NPDES permit. Pollutants involved include copper, ammonia, and zinc. Exceedances of the ammonia limits constitute the vast majority of the violations. The compliance agreement requires the city to pay an administrative penalty of $134,500. The city has achieved compliance with its NPDES permit.