Mont. Code Ann. § 85-3-413

When a petition signed by not less than 20% of the qualified electors of the county, as determined by the vote cast for the office of governor at the last preceding gubernatorial election, requesting an election upon the establishment of a weather modification authority is presented to the board of county commissioners not later than 90 days prior to the next general election, the board of county commissioners shall submit the question to the electors of the county at the next general election. Upon approval by a majority of the votes cast, the board of county commissioners shall by resolution establish an authority as described in 85-3-411 with all powers set out in this part, including the power to certify a tax levy as provided by 85-3-422.