Ben Siller of Denver Environmental Health uses the Nasal Ranger, a device that helps officials measure the intensity of an odor. (Hyoung Chang, Denver Post file)

Fresh rules targeting marijuana, pet food odors OK’d by Denver council

The Denver City Council on Monday approved a beefed-up odor-control ordinance that will require commercial marijuana grow facilities and other smelly businesses to freshen up.

After months of grueling debate over marijuana industry caps, resulting in a split vote last week, the odor ordinance was easy for council members. They’ve had repeated pushback from community activists over the impact of grows on neighborhoods near the industrial areas where they’re concentrated — starting with the smells.

The council approved the proposal 13-0 in a block vote, with no new debate.

In addition to expanding who can file complaints, the ordinance will require certain types of businesses to submit odor-control plans to the Department of Environmental Health for smells they expect to produce and then follow them.

The rule applies to marijuana grows, and also operations and businesses that manufacture pet food, process meat byproducts, manufacture asphalt shingles or coating materials, refine oil, preserve wood or treat sewage.

Health officials have estimated that more than half of marijuana grows in the city already use some kind of odor-filtration technology.

The health department plans to convene an odor advisory group, which is expected to adopt detailed odor rules by early next year. The requirement for odor-control plans would take effect 90 days later.

Jon Murray: 303-954-1405, or @JonMurray

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