The Department of Environmental Quality (DEQ) is accepting a second round of comments on a proposed Montana Pollutant Discharge Elimination System (MPDES) permit for snowmelt associated with snowmaking using treated wastewater on Spirit Mountain, Andesite Mountain, and the Spanish Peaks base area near Big Sky. 

Spanish Peaks Mountain Club (Spanish Peaks) applied to DEQ for a Montana Pollutant Discharge Elimination System (MPDES) permit to discharge disinfected and treated wastewater to tributaries of the Middle Fork West Fork Gallatin River upon snowmelt. DEQ previously issued a draft permit and Environmental Assessment (EA) for the snowmaking project in May 2024 for public comment.  

The newest drafts reflect changes made after DEQ reviewed information submitted during the 2024 public comment period. 

If the MPDES permit is finalized, it would allow Spanish Peaks to source treated wastewater from Big Sky County Water and Sewer District wastewater treatment facility for use in snowmaking. The permit would authorize Spanish Peaks to discharge the resulting runoff from snowmelt to tributaries of the Middle Fork West Fork Gallatin River. The permit proposes limits on pollutants that can be in the treated wastewater and would require additional monitoring of the snowmelt and stream.    

Snowmaking activities would add to natural snowpack and recharge of ground water in the area. The permit specifies snowmaking would occur between Nov. 1 and Jan. 15 each year (dependent on weather conditions) with a maximum of 76 days of snowmaking. Most snowmaking is anticipated to occur mid-November to mid-December.  

DEQ is accepting public comments on MPDES permit MT0032174 and the associated draft EA from Feb. 3 – March 6. Visit https://deq.mt.gov/News/publiccomment-folder/PN-MT-25-02-MT0032174 to view the documents and learn how to submit a comment.