Settlement reached over 2016 gas explosion in Seattle's Greenwood neighborhood

OLYMPIA, Wash. – Pipeline safety regulators and Puget Sound Energy have reached a settlement agreement in response to the complaint filed against the company for the 2016 natural gas explosion in Seattle's Greenwood neighborhood, the Utilities and Transportation Commission announced Tuesday.

The settlement would impose a total penalty of $2.75 million, suspending $1.25 million on the condition that PSE completes a comprehensive inspection and remediation program.

The settlement will be presented to the three member commission, which can choose to accept, reject, or modify the agreement.

In September, UTC pipeline safety staff released the results of their investigation into the cause of the March 9, 2016, explosion that injured nine firefighters and caused extensive property damage. The investigation identified the immediate cause of the explosion as damage to an above-ground service line. The investigation also determined that the line was improperly retired in 2004, and therefore remained active until it was shut off after the explosion.

The complaint alleged five violations related to improper deactivation of a pipeline and failure to perform periodic gas leak surveys and corrosion tests as required by pipeline safety regulations. In the settlement, PSE did not contest the five violations.

In the settlement, staff and PSE agreed that one factor in the explosion was the improper retirement of the service line by a contractor in 2004. The parties also agreed that another factor was the physical damage caused by trespassers who regularly accessed the space where the line was located.

The compliance program, if approved by the commission, will require PSE to identify, inspect, and remediate more than 40,000 retired service lines.