The Environmental Quality Board proposed to amend Minn. r. 4410.4300 to clarify how greenhouse gases are to be treated under the air pollution mandatory environmental assessment worksheet category. Currently, the environmental review program rules do not define "air pollutant," and the Board is soliciting comments on whether the threshold of 250 tons per year for other sources permitted under the program is appropriate for greenhouse gas emissions. http://www.comm.media.state.mn.us/bookstore/stateregister/35_14.pdf pp. 545-46.