Four firefighters and three deputy sheriffs who were enveloped by a cloud of sulfuric acid were hospitalized Friday for respiratory problems associated with the leak at a Union Carbide plant near the Tooele-Salt Lake county line.

Deputies responded to the plant, 12385 W. 21st South, shortly after 11 a.m. Friday on a report of an industrial accident in which a man fell from a tank, said sheriff's Lt. Bill Van Wagenen."As our cars arrived, Lt. Bernard Hahn thought that he was driving over melted snow. When he drove over it, a big cloud developed," Van Wagenen said. "When he got out of the car, all the under seal was dripping off and boiling on the ground."

The sulfuric acid apparently leaked from a pipe that was damaged by an icicle. Hahn's shoes and tires also were melting from the acid, officials said.

"No one knew about it, the tank leaking, until we drove through it," the lieutenant said.

Two deputies who responded to the scene saw the cloud go up and ran toward Hahn. The three, along with four Salt Lake County firefighters, were treated at Pioneer Valley Hospital and released.

"All except my car" have been been released, said Van Wagenen. "It's been impounded to be decontaminated."

County fire crews were at the scene for more than six hours, putting soda ash to mop up the spill. "The area is all cordoned off and they are trying to stabilize it."