DEQ Sage Grouse Advisory
The goal of the Montana Pollutant Discharge Elimination system (MPDES) program is to control point source discharges of wastewater such that water quality in state surface water is protected. Levels of water quality that are required to maintain the various beneficial uses of state surface waters are set forth in the Water Quality Standards (WQS).
All point sources of wastewater discharge are required to obtain and comply with MPDES permits. The effluent limitations and other conditions for certain categories of wastewaters are required to be treated to federally-specified minimum levels based on available and achievable water treatment technologies. Additionally, effluent limits and permit conditions are established to protect beneficial uses and applicable WQS.
The Nondegradation Rules are a part of the WQS that apply to new or increased sources of pollution. These rules prohibit significant increases in discharge of toxic and deleterious materials to state waters, unless it is affirmatively demonstrated to the DEQ that a change is justifiable as a result of necessary economic or social development and will not preclude present and anticipated use of these waters.
Each MPDES permit issued is designed to protect the state surface water quality at the point of discharge. In addition, recognizing the dynamic nature of streams and the potential additive or cumulative effects of pollutants, MPDES permits also address stream reach or basin-wide pollution problems. A calculation process called total maximum daily load (TMDL) is used to apportion allowable pollutant discharge levels among the various dischargers. If reductions of a given pollutant in a stream reach or basin are found necessary to meet WQS, the TMDL process is used to apportion the reductions among the dischargers in that reach or basin.
The program is funded by application and annual permit fees. Activities of program staff include public education, reviewing applications, determining effluent limits and best management practices, environmental assessments, public participation and information retrieval, effluent and instream data review and management, field inspections, enforcement, regulation and guidance preparation, program planning and administration.