The Deep Fork National Wildlife Refuge is located outside the City of Okmulgee, Oklahoma and was established in 1993 to protect an important bottomland hardwood forest and emergent wetland habitat along the Deep Fork River for the benefit of migratory birds and other native fish and wildlife species. On August 26, 2000, the City of Okmulgee's Publicly Owned Treatment Works released an undetermined amount of sewage and sewage sludge into Okmulgee Creek, a tributary of the Deep Fork River. A plume of raw sewage and sewage sludge migrated slowly downstream, due to low seasonal flow rates, into the Deep Fork River. This plume included ammonia in toxic quantities, as well as other unidentified hazardous substances. The plume caused mortality to fish, mussels, and other aquatic species along 11 miles of the Deep Fork River that flows through the Refuge. The Trustees jointly recovered restoration funds from the City of Okmulgee through settlement negotiations, as documented in the Consent Decree. The Trustees have completed all restoration actions described in the Restoration Plan and Environmental Assessment for Injuries to Natural Resources on the Deep Fork River National Wildlife Refuge by the City of Okmulgee, Okmulgee County, Oklahoma and Partial Settlement for injuries from the Hardage-Criner Superfund Site in McClain, County, Oklahoma.