On a sunny day in October, Mike Arnold swings open the door to his barn storehouse outside Eugene, Oregon, and takes a big whiff. The odor hits him immediately, a sweet and skunky wall of cool air. “Smells like money,” Arnold says in the Missouri drawl, gazing out at row after row of make shift wood-and-mesh shelving, where 12,000 pounds of marijuana were lying to dry.

Following close behind, in colorful glasses as well as a tweed jacket, is the cannabis engineering virtuoso in charge of keeping that pungent odor safely in the confines of the building: 39-year-old Daniel Gustafik. Gustafik continues to be building out pot grow rooms for 25 years, designing novel solutions for from irrigation to lighting to humidity control in hidden sub-basements and on off-grid homesteads long before anyone can even conceive of Bob Marley-branded weed sold openly in sleek boutiques. He and his company, Hybrid Tech, are now regarded as being the best inside the game when it comes to setting up industrial-scale legal cannabis operations. Previously 4 years, they’ve completed more than a hundred projects in 37 states as well as 2 countries.

Even as cannabis air quality plan becomes increasingly mainstream, not everyone is feeling chill about legalization. Pot reeks, and pot being grown or processed at commercial scale reeks a lot more. Some states and municipalities have included specifications about odor control in their medical and recreational marijuana regulations.

But cannabis’s federally illegal status creates all sorts of thorny problems. Last June, a 10th-circuit court in Colorado decided that a family who complained regarding the “noxious odors” provided by a cannabis venture next door had sufficient grounds to argue the aroma had hurt their house values, and could therefore sue for triple damages under federal racketeering law. The ruling sent shockwaves from the legal weed industry, triggering similar lawsuits in Oregon and Massachusetts, and potentially establishing a precedent in which private citizens could use federal law to topple locally licensed pot businesses. This means that marijuana’s distinctive stink could really be worse for the legalization movement than anything Attorney General Jeff Sessions has been doing, as well as the continued success of state-legal weed is influenced by rigorous odor-proofing.

Take Arnold’s cavernous drying barn, nestled among rolling hills and maple trees. This, Gustafik says, is his magnum olfactory opus: a 5,000 sq . ft . facility, outfitted in a mere 21 days, and operating in a county dmdwjs the strictest marijuana scent control rules on the planet. Before Oregon legalized recreational weed, a lot looser medical cannabis law have been in position for many years, attracting inconsiderate growers familiar with the black market. The noise, traffic and stink annoyed locals who, in turn, annoyed officials using their complaints. So when it came time and energy to regulate adult use, some counties preemptively took a difficult line. In a meeting to find out what these rules would look like in Clackamas County, one community member compared the smell to “skunk dipped in turpentine and gym socks.” Consequently, the Clackamas ordinance ultimately specified from the angle of exhaust vents to the strength of the fans utilized to circulate air. Lane County, where Arnold’s barn is found, ultimately decided to utilize the same language inside their ordinance.