scope:

Description of Driving Event:

A casing in Cluster #1 of the Underground Air Storage Facility (UASF) ruptured releasing high pressure air (3000 psig) into the substrate at about 500 ft below the surface. Although, quick action by the crew isolated the UASF from the rest of the distribution system, the entire 5x106 SCF of air, stored in the UASF, was released through the rupture. The released air created a crater around the affected cluster and sprayed mud onto the surrounding area for a radius of approximately 150 feet. Damage was localized to the one cluster. However, personnel that had entered the area to attempt to isolate the individual clusters from the manifold were exposed to streams of water and mud when evacuating the area.