MT HB736

Point source dischargers to Montana surface waters may use nutrient loading offsets or trading credits to satisfy water quality discharge permit requirements, including effluent limitations derived from waste load allocations

Offsets and trading credits are authorized when a net decrease in nutrient loading is achieved within the same or immediately adjacent USGS-designated 12-digit hydrologic unit code subbasin through reductions from other point or nonpoint sources

Trading credit ratios set at 100% for point source reductions, 80% for up-gradient nonpoint source reductions, and 50% for down-gradient nonpoint source reductions

Department must establish statewide methodologies for calculating nonpoint source offset amounts based on riparian fencing (feet of streambank), riparian vegetation (acres), wetland development in irrigation return flow areas, and septic system removal

Requires amendment of DEQ Circular DEQ-13 (Montana's nutrient trading policy from December 2012) and ARM 17.30.1701; effective immediately upon passage and approval