SOUTH CHARLESTON, W.Va. - Union Carbide, already reeling from back-to-back chemical releases at two of its plants this month, had a third leak - this time of an unknown amount of hydrochloric acid.

The leak Monday night was created by the combination of 35 percent hydrogen chloride and 65 percent water. There were no injuries and no evacuation and the leak apparently was confined to the plant grounds.

Hydrochloric acid can cause irritation of the eyes, shortness of breath and some nausea if inhaled.

As in the first two leaks in West Virginia's "Chemical Valley," the chemical scare raised questions about Union Carbide's emergency response system.

"We had a problem with the line of communication between Union Carbide and our emergency communications center," said Lt. Larry Mullins of the Kanawha County Sheriff's Department. "It took some time before we actually received word of it."

Carbide spokesman Mike Lipscomb said the company did immediately notify the South Charleston fire department, the public safety director in neighboring Charleston and county emergency services.

Lipscomb said a gasket blew about 8:30 p.m. on a silicones manufacturing vessel. He said a company fire brigade poured water on the area for about 45 minutes to knock the chemicals out of the air, creating large plumes of steam and vapor.

But Mullins said his office, which is supposed to be the first notified, never received any warning from Carbide. "The way we found out about it is through the news media about 9:15 p.m.," he said.

Mullins said he had "no idea" what caused the communications snafu.

After an Aug. 11 leak of pesticide ingredients at its Institute plant and an Aug. 13 leak of brake fluid chemicals at the South Charleston unit, Carbide officials vowed to spend millions of dollars to reduce emissions at all of its plants and to be quicker about notifying authorities in event of a leak.

Dozens of people were sickened by the Institute leak and a handful reported symptoms from the Aug. 13 spill. The most infamous Carbide incident occurred Dec. 3 , 1984, when a methyl isocyanate leak killed about 2,500 people at a plant in Bhopal , India.