DENVER - Now that retail marijuana is legal in Colorado, the facilities that grow retail marijuana must be inspected by environmental health inspectors.
There are currently more than 300 marijuana grow facilities in Denver. To get them open in time for the start of the year, the Denver Department of Environmental Health previously signed off on the retail marijuana licenses with the promise of a thorough environmental health inspection at a later date.
"Some of the things we've already talked to them about is odor; asking them to voluntarily mitigate odors, and we're also looking at their light bulb disposal [and] how their handling their waste," said Denver Department of Environmental Health investigator Ben Siller.
7NEWS was with Siller as he walked through the Medicine Man grow facility in northeast Denver.
"Currently in Denver, we have an odor regulation that's based on the intensity of the odor," said Siller. "We haven’t had any marijuana grow facilities that have violated our odor standard for intensity."
In September, Siller showed 7NEWS a marijuana odor detection device known as the "nasal ranger." It resembles binoculars for the nose.
When the Denver Department of Environmental Health receives a marijuana odor complaint, an investigator uses the nasal ranger to detect how strong the smell of marijuana is outside of the facility. So far this year, Denver has received a total of eight marijuana odor complaints from grow facilities. Siller said none of those eight complaints were intense enough odors to warrant a citation or fine based on Denver’s current odor ordinance.
"When a plant is in the flowering stage or in the drying curing room, those are the most odorous points," said Siller.
There has not been an odor complaint against Medicine Man. The owners of the grow facility have voluntarily installed a carbon filtration system -- essentially an air filter -- to reduce the marijuana odor as it vents from the building.
"What we're doing is actually pulling the air through that and it's all in an attempt for odor mitigation," said Medicine Man spokeswoman Elan Nelson. "We can't cure the odor problem of marijuana, but we're doing our best to be a good neighbor to those in our area."
As the air inside the building escapes through the vents in the ceiling, it filters through four long carbon-filled canisters, to help eliminate the odor from being detected outside. There are two sets of four filters set up inside the warehouse.
"As far as the carbon filtration system, that was a very high expensive that we took upon ourselves. It's not mandated. It's not required yet. I foresee that it will be at some point," further explained said Nelson. "It's a significant expense. That's why a lot of dispensaries chose not to do it, which is understandable, but hopefully as this industry keeps evolving and maturing, it's going to become something that becomes more cost effective for all of us to do."
Nelson said the filters can be vacuumed, but need to be changed every six months.
"We don't want to be bad neighbors. We don't want to be upsetting them and they constantly have the smell of marijuana -- and some people like that smell, we certainly do -- but a lot of people do not," said Nelson. "A smaller odor footprint is what we've created."
The city also inspects for how a grow facility disposes of light bulbs.
"There are requirements they have to be in a container and marked as used lamps. It's a requirement because they contain mercury. They're put in a special container and marked and then they need to contract with a supplier or a company to dispose of those properly," said Siller.
"We have 212 flowering lights," said Nelson.
During the inspection, Siller was shown a shelf with boxes of bulbs marked "new" and "used."
"Why you need to store them appropriately is you want to avoid breakage. Then, the mercury would be on the ground and become an exposure risk," said Siller. "(We) give them some advice, see that they are containing [the light bulbs] properly [and] ask them who is disposing of it. We'll note that information [and] if we note any discrepancies or we think there is non-compliance, we'd make a referral to the EPA and the state health department," said Siller.
Siller also makes sure that any cleaning done inside the grow facility does not allow water into storm water drains outside.
"We'll discuss pesticide use," said Siller. "One of the other things that we've learned is, we've had some facilities that we've seen them washing equipment outdoors. We don't want that because it's a discharge to the storm water system."
Siller also asked finds out how marijuana waste is handled; if it's thrown in the trash for a landfill or if it's composted, which the city recommends.
"For all of the marijuana waste, we make sure that it's unusable and unrecognizable. We'll shred the leaves and we'll mix them with the soil that we're using, and then sometimes we'll put bleach on that as well to make double certain that it's not going to be reusable for any purpose, and then we put that in the dumpster," said Nelson.
The inspection itself appeared to be educational, providing recommendations and not citations.
"We get an indication of the size of the facility because one of the other things that we're doing is trying to do some data gathering," said Siller. "We'd like to know how many facilities are out there, how large the facilities are; if on down the road there is any consideration for an odor regulation specific to marijuana grow facilities, that's information that we can provide to the regulators to help them with their decisions."
"We are definitely held to very strict, rigid standards," said Nelson. We want to make sure that everything that the state and local officials are telling us to do [that] we remain absolutely in compliance so that we can remain in business."