The Pollution Control Agency adopted permanent rules relating to water quality, including 7050.0220 - Specific Water Quality Standards By Associated Use Classes, 7050.0222 - Specific Water Quality Standards For Class 2 Waters Of The State; Aquatic Life And Recreation, and 7050.0470 - Classifications For Surface Waters In Major Drainage Basins. http://www.comm.media.state.mn.us/bookstore/stateregister/32_37.pdf pp. 1699-1728.