Plans to mitigate the impacts of recreational marijuana sales in Missoula continue to move forward with proposed zoning that would prevent the saturation of dispensaries in a single area and ensure storefront windows remain active and transparent.

But while the city's planning department finalizes its proposals for approval by the planning board and City Council, new questions have come up, including emergency response plans for chemical manufacturing, and the energy consumption that comes with cultivation.

“I fully support legalization, but I'm very concerned about the production processes used today to produce pot on an industrial scale,” said planning board member Neva Hassanein. “I think it's better to get in front of it now rather than wait and try to impose something on existing businesses later.”

City planners said energy concerns have risen, but potential remedies or controls haven't been detailed. Unlike the county, the city hasn't passed any measures regulating energy-intensive businesses.

Last year, Missoula County made permanent its ordinance surrounding cryptocurrency mining operations. Among other things, a mining operation must develop or purchase enough new renewable energy to offset its electrical consumption.

“We're reluctant to jump the gun without more information in regards to energy consumption in this industry,” said planner Spencer Starke. “If we were to propose something, it would have to be robust with evidence and data to support it, and at this time, it's not available to us.”

Scholarly articles on the energy impacts of marijuana cultivation aren't hard to find, and they all suggest the impacts are intense. A pioneering study in 2012 on the carbon footprint of indoor cannabis production estimated that cultivation consumed as much as 1% of all electricity in the U.S. at that time.

In Colorado, grow facilities in 2014 consumed around 0.4% of the state's total electrical use while in Denver County, cultivation consumed 2.2% of available electricity. In Washington, estimates have suggested that cultivation accounts for 1% of that state's total demand.

While Colorado and Washington grapple with marijuana's energy impacts, some members of the planning board want to get ahead of the problem in Missoula.

“We need to look at what kind of production is anticipated, not only within the city but the county,” said Hassanein. “We have climate change goals. There's got to be evidence to how much production utilizes in other places, and guesses as to what's anticipated here. We have to get out in front of this on the energy thing.”

According to city, around 70 cannabis related business are already operating in Missoula. Of those, 50 are medical marijuana dispensaries while the remaining 20 are cultivators and manufactures.

With legalization set for Jan. 1, planners are proposing a number of zoning amendments to address various concerns around public health, urban form and neighborhood character. Some fear a saturation of dispensaries in certain areas, including downtown and the intersection of Russell Street and Broadway.

“If dispensaries continue to cluster, they will lead to a lack of diverse uses in a neighborhood, affecting urban form and access to amenities in certain areas,” said city planner Cassie Tripard. “To obscure cannabis products and provide security, many dispensaries have installed frosted glass or opaque windows. This prevents a lack of storefront transparency. It alters urban form and neighborhood character.”

As proposed, manufacturing in Missoula would be restricted to industrial districts while cultivation would be regulated through zoning based upon the size of the operation. Neither would be permitted as a home occupation while sales would be codified as a general retail use.

State law won't allow drive through operations, and it restricts marijuana advertising. Cannabis cannot be sold on the same premise as alcohol and tobacco sales, and cultivation and manufacturing can't be visible from public areas.

State law also prevents dispensaries from locating within 500 feet of a school or church. In addition to that, the city is proposing a 500 foot buffer between individual retail dispensaries to prevent clustering in one area.

“The buffer produces a de facto cap because there's a limited amount of retail space available, and a finite amount of spaces zoned for this type of retail,” said Starke. “With the buffer in place, we're hoping that will help limit the effects while not limiting a potential business owner's options.”

The Missoula Planning Board is set to consider the proposed zoning on Nov. 2, followed by the City Council on Nov. 15. Final consideration is set for Nov. 29 and will go into effect before Jan. 1, when recreation use begins.