Total Maximum Daily Load (TMDL) for Biochemical Oxygen Demand (BOD5) in the Surface Waters of Ward Cove, Alaska

摘要

Section 303(d)(1)(C) of the Clean Water Act and EPA's implementing regulations (40 CFR Part 130) require the establishment of Total Maximum Daily Loads (TMDL) for the achievement of state water quality standards. A TMDL is an implementation plan which identifies the degree of pollution control needed to maintain compliance with standards using an appropriate margin of safety. The focus of the implementation plan is the reduction of pollutant inputs to a level (or 'daily load') that fully supports the beneficial uses of a given waterbody; however, other considerations are needed to complete the TMDL process. The components used to address water quality problems through the TMDL process include effluent limits and monitoring requirements. The state of Alaska has identified Ward Cove as being water quality-limited for dissolved oxygen. Based on an assessment of the problem of low dissolved oxygen (DO) in Ward Cove, a draft TMDL for this waterbody was noticed to the public on August 4, 1993, in conjunction with the draft permit for Ketchikan Pulp Company. This final TMDL is established for Five Day Biochemical Oxygen Demand (BOD5), a parameter directly related to the impact of a discharge on DO levels in a receiving water.