NTSB Opens Public Docket for Coolidge, Arizona Pipeline Rupture Investigation


Aerial image of accident scene following the explosion.

​​(This photo illustration shows the aerial view of the accident scene following the explosion. Photo courtesy of the Pinal County, Fire Investigation Task Force)​​

​​​WASHINGTON (Sept. 15, 2022) — The National Transportation Safety Board opened the public docket Thursday as part of its ongoing investigation of the fatal, Aug. 15, 2021, natural gas transmission pipeline rupture and fire near Coolidge, Arizona.

The docket for this investigation includes more than 1200 pages of factual information, including reports on pipeline operations, human performance, metallurgic​al testing, and emergency response efforts. The docket also includes interview transcripts, photographs, employee training records, and other investigative materials.

The docket contains only factual information collected by NTSB investigators; it does not provide the final report, nor does it contain analysis, findings, recommendations, or probable cause determinations. As such, no conclusions about how or why the rupture occurred should be drawn from the information within the docket. Analysis, findings, recommendations, and probable cause determinations related to the rupture will be issued by the NTSB in a final report at a later date.

A 30-inch pipeline owned and operated by Kinder Morgan, Inc., ruptured and released natural gas that ignited. The rupture resulted in an explosion, fire, and ejection of a 46-foot section of the pipeline. One residence was destroyed by the explosion and subsequent fire, resulting in two fatalities and one injury.

​Additional material may be added to the docket as it becomes available.

The public docket​ for this investigation is available online.

To report an incident/accident or if you are a public safety agency, please call 1-844-373-9922 or 202-314-6290 to speak to a Watch Officer at the NTSB Response Operations Center (ROC) in Washington, DC (24/7).