July 26, 2022 9:52 AM
July 32 - Methane Detection: BoulderAIR ECC Air Station
The BoulderAIR ECC Station detected peak methane concentrations of 5,328 ppb on July 23, 2022 at approximately 12:07 a.m. The plume was detected for approximately 30 minutes beginning at 11:40 p.m. on July 22.
Since exposure to methane in the environment is not known to cause any adverse health effects, there are no established Heath Guideline Values (HGV) associated with methane. The gas is a potent greenhouse gas and is flammable in concentrations greater than 5% by volume. For context, the concentrations measured on July 23 hit a maximum of 0.00053% by volume (~1/10,000th the lower explosive limit for methane).
Associated Volatile Organic Compounds (VOCs) were slightly elevated above baseline during portions of the methane plume event, though none approached any established HGVs. Winds were light and variable during the observed plume.
The Colorado Department of Public Health and Environment (CDPHE) was notified of the event on July 25. CDPHE has stated, given no danger was posed to the public at any time, their investigation into the event would consist of continued monitoring to determine the frequency and severity of similar events.