SAN JOSE (CBS SF) — Dramatic video just released shows an explosion in a steam pipe vault that injured a worker at the Valley Medical Center in San Jose and highlights a dispute between the county and the general contractor over construction delays.

The video from nearly a year ago shows workers activating a steam pipe system for the first time at the construction site which is undergoing a $300 million expansion that has been fraught with delays.

In the video, loud banging noises can be heard, followed by the workers’ growing concern for their safety.

“Yeah Joel, maybe you should step out for a minute,” another worker can be heard saying to the worker in the vault.

As the worker slowly climbs a ladder out of the vault, a steam pipe below him exploded, shooting 200F degree plus steam.

“The worker could have been killed down in the vault, had he been in there. That’s the worst case. The least case is some sort of blunt trauma, and being scalded by the hot temperature piping,” Santa Clara County Facilities Director Jeff Draper said.

The worker survived with only minor injuries, but county offficials say the explosion shows faulty design and safety practices by Turner Construction, the general contractor that designed and built the system.

“I’m concerned that they’re not paying attention to the details,” Draper said.

Although the incident happened some time back, the county claims a worker produced it just yesterday amid the county’s threat to fire Turner Construction.

The county says the steam system has yet to be redesigned and rebuilt, and is one of many problems adding to years of delays on the construction project.

“We’re prepared to just lock them out,” county executive Jeff Smith said.

Turner Construction said in a statement that safety is its number one priority but the company refused to comment on the explosion, saying it’s already given a full report to the county.

A company spokesman accused the county of trying to divert attention away from its own mismanagement of the VMC project.

“The real objective of today ought to be how do we find a path forward,” said spokesman Larry Kamer. “How do we stop pointing a finger of blame at Turner and its subcontractors.”