GEORGETOWN, Colo. (AP) – A chemical explosion and fire at a hydroelectric generating plant outside this mountain town trapped five workers in a water tunnel about 1,000 feet below ground.

All five were alive and were communicating with rescuers, Clear Creek County Emergency Director Kathleen Gaubatz said.

It was not clear whether the workers were hurt. Crews were rappelling down a 55-degree incline to reach the them.

Gaubatz said epoxy paint had exploded but the structural integrity of the dam was not compromised.

The Cabin Creek Station plant, owned by Xcel Energy, is about 30 miles west of Denver.

“They’re up a ways from the fire, a safe distance, waiting for the appropriate fire and rescue personnel to respond,” Xcel spokesman Tom Henley said.

Henley said the fire broke out during routine maintenance on an underground channel called a penstock, which delivers water from a reservoir to turbines that generate electricity.

The maintenance was being done by a contractor, but Henley did not know the contractor’s name or any details of what the workers were doing.

AP-ES-10-02-07 1823EDT