May 24, 2022 4:00 PM
May 8 - BoulderAIR ECC Station Fuel Detection
The ECC VOC plume event detected on May 8th at 6:05 a.m. shows a chemical signature that suggests that the plume originated from a release of liquid petroleum hydrocarbon fuel, such as gasoline or diesel fumes. During the peak, natural gas tracers, e.g. methane and ethane were recorded close to normally seen ambient levels. In contrast, liquid fuel components, i.e. butane and pentane isomers, and benzene all showed elevated mole fractions when compared with background levels. This suggests a liquid fuel, for instance gasoline source, rather than natural gas fumes. At the time when the plume was detected, the wind was blowing from the south (167-200 degrees).
The Colorado Department of Public Health and Environment (CDPHE) was notified of the event on 5/10/2022. The CDPHE acute 1-hour exposure Health Guideline Value (HGV) for benzene 9ppb, and a spokesperson for the CDPHE stated “Federal and state agencies set health guideline values (HGVs) to identify levels of pollutants that may cause health impacts. Health guideline values are not regulatory. Agencies set HGVs well below the levels known to cause harmful health impacts. HGVs help us identify contaminants of greatest health concern. We can use this information to inform future policy decisions and research projects. If CDPHE measures a pollutant above a health guideline values, it does not mean health impacts will occur. It means more investigation is needed. The continued monitoring that the Town of Erie has is the kind of additional investigation that can be used to understand more about how often elevated levels may occur.”