Is reporting “significant damage” transparent? Assessing fire and explosion risk at oil and gas operations in the United States

Oil and gas (O&G) operations are periodically accompanied by fires and explosions. The frequency of these incidents is not well known, particularly at modern sites that increasingly use advanced techniques, such as horizontal drilling and hydraulic fracturing. The objective of this work is to determine the rate of fires and explosions at O&G sites in Colorado and Utah and apply this information to evaluate the proximity of these incidents to residences. Between 2006 and 2015, a total of 116 fires and explosions in Colorado (0.03% of active wells) and 67 fires or explosions in Utah (0.07% of active wells) were reported at O&G operations. The higher percentage of fires or explosions per number of active wells in Utah compared to Colorado (Rate Ratio = 2.49, p < 0.01) is likely influenced by the mandatory self-reporting requirements in Utah and the more lenient self-reporting in Colorado. The average number of residences within 1609 m of the reported incident was 31 (median = 3, SD = 131) in the Denver Julesburg Basin and 4 (median = 0, SD = 10) in the Piceance Basin of Colorado. To our knowledge, this is the first systematic analysis of fires and explosions at O&G sites and offers insight into the rate and reporting of these events.