Agency finds no short-term health risks and will continue to conduct air quality monitoring of the facility
Denver (March 18, 2025): The Colorado Department of Public Health and Environment has completed its initial investigation and response to air quality issues at the Platte River Biogas, LLC facility in La Salle. After a monthlong air monitoring effort and coordination with local agencies, CDPHE determined there is no acute public health risk from short-term exposure to chemical emissions at the facility for Platte River Biogas employees or the public at this time.
The Platte River Biogas facility processes manure into renewable gas. CDPHE began its most recent investigation in December because air monitors detected elevated levels of hydrogen sulfide onsite that CDPHE wanted to further evaluate. CDPHE also wanted to follow up after receiving concerns about air quality from nearby residents. Hydrogen sulfide is a toxic air contaminant that can smell like rotten eggs and can be harmful to inhale at high levels or for long periods of time. It is emitted during industrial activities including waste collection and processing. In mid-December, CDPHE’s initial rapid-response air monitoring effort determined monitoring was warranted. Next, CDPHE contacted the residences within 3,000 feet of the facility and began a more extensive monitoring effort.
CDPHE continuously monitored air quality nearby the facility from mid-December 2024 to mid-January 2025. Monitoring determined the levels of hydrogen sulfide, benzene, and toluene were below those associated with short-term health impacts.
Later this year, CDPHE will conduct further air monitoring at the facility to better understand how emissions at this location change during different seasons. CDPHE can then use this information to better evaluate how chronic exposures could impact public health in the surrounding area.
CDPHE will continue to study hydrogen sulfide levels in Weld County and across the state as part of HB 22-1244: The Public Protections from Air Contaminants Act. The state is also working to propose health-based standards and emission control strategies for five priority air toxics in Colorado, including hydrogen sulfide and benzene.
To report air quality concerns in Weld County, please contact the Weld County Department of Public Health and Environment at 970-304-6415 or submit a concern online.
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