Boulder County has hit pause on its own shutdown plans for the longtime Cemex cement plant east of Lyons, quietly reinstating the facility’s permit and reopening a fight that has simmered in the valley for years.
The nonconforming-use permit is back in place for now, after county staff reversed an earlier order that would have forced the plant to stop operating. That about-face has neighbors asking what changed, while county officials say they were relying on bad information the first time around.
As reported by 9News, Boulder County’s Community Planning & Permitting director now says the earlier shutdown order “was based on a faulty study.” Staff reinstated the permit after reexamining that analysis.
The county’s original move to terminate the plant’s long-standing status came in an April 10, 2024, letter. In that notice, Boulder County cited a traffic study showing truck trips jumped from an average of 593 per day in June 2022 to 1,283 per day in June 2023. The notice says that exceeding a 150-ADT threshold triggers special-use review and that the spike “constitutes an enlargement or alteration” of the use under the county land-use code.
The Lyons plant has been a neighborhood lightning rod for years, with residents and reporters documenting repeated fugitive-dust events and high emissions. State air regulators recently hit Cemex with about $1.3 million in fines tied to dust and emissions violations, upping the pressure on local officials, according to The Colorado Sun.
For its part, Cemex is not acting like a company on the brink of closure. The firm said it is reviewing the county’s latest action and plans to respond within the 30-day window while continuing to run the plant under existing conditions, Denver7 reports. The company also told the station that the Lyons facility supplies cement for regional construction projects and employs more than 100 people locally.
What happens next
Under county rules, Cemex now has 30 days to make its next move. The company can submit evidence arguing the original termination was in error, reduce operations to address the county’s concerns, or appeal directly to the Board of County Commissioners. Those paths are laid out in the planning director’s letter.
In the meantime, the plant is allowed to keep operating at current levels until the county issues a final determination, according to Boulder County.
Neighbors and politics
Local advocacy groups such as Good Neighbors of Lyons and Save Our Saint Vrain Valley have pushed hard for the plant’s closure, arguing that frequent dust incidents and emissions are taking a toll on nearby communities.
The conflict has grown well beyond a simple land-use dispute. A coalition of mayors and elected officials across Boulder County joined the calls for action on the plant, The Colorado Sun reports.
Legal stakes
If the county ultimately orders the plant closed, the messy and expensive work of reclaiming the quarry and plant site would fall under the jurisdiction of the Colorado Division of Reclamation, Mining, and Safety. Any county open-space options tied to the site could also come into play. Reclamation timelines and bonding are handled at the state level.
Separately, state air-permit enforcement by the Colorado Department of Public Health & Environment operates on its own track and could impose additional fines or compliance requirements beyond what the county does for land use. For more details, see guidance from the Colorado Division of Reclamation, Mining and Safety and the Colorado Department of Public Health & Environment.
The permit reinstatement is just the latest twist in a long-running local fight that now seems destined for appeals, more regulatory scrutiny, and additional public hearings. Both plant supporters and opponents say they will be watching every new filing from the county as the clock ticks toward a final decision.
