A cracked valve on a pipeline caused gasoline to spew into the air and forced closure of a one-mile stretch of Route 22 in Murrysville yesterday, creating massive traffic delays throughout the day.

No one was injured, but Westmoreland County officials shut down the busy roadway between School Road and the Cozy Inn Cut-off. They evacuated all businesses in the area, three nearby schools and a personal care home for senior citizens.

Officials also shut off electricity and natural gas service to reduce the chances of an explosion or fire.

It was unclear last night how much gasoline had leaked from the pipeline, owned by Sunoco Logistics. The leak was shut off by noon, and environmental cleanup crews deployed vacuum trucks in three areas along Turtle Creek and Route 22 as far east as Pleasant Valley Road to suck up the gasoline.

"As it comes down, we're trying to gather it up," said Dan Stevens, public information officer for the county's public safety department.

The leak began about 9 a.m. when a two-person Sunoco maintenance crew was working on a portion of the 8-inch pipeline behind Hoss's Steak and Sea House on Route 22.

A 2-inch ball valve failed, causing gasoline to shoot out of the pipe and spray into the air, said Helen Humphreys, spokeswoman for the state Department of Environmental Protection.

"It looked like it was raining -- raindrops of gas," said Margie McAndrew, a manager at Hoss's.

She said she saw a cloud of smoke rise as high as 70 feet in the air. She and four other restaurant employees then fled.

Dozens of ambulances helped transport 144 residents of the Redstone Highlands personal care home to Murrysville Alliance Church on Old William Penn Highway. Those with special needs were transferred to other Redstone facilities. By 7 p.m., Mr. Stevens said, the residents had safely returned home.

The Franklin Regional School District's Web site said students at Newlonsburg and Heritage Elementary schools and the middle school were moved to the senior high school, from which they were dismissed.

No homes were evacuated.

Mr. Stevens said residents should expect the odor of gasoline to persist for a few days, but they can call 911 if they are concerned.

The pipeline rupture was 30 feet up a slope from Turtle Creek.

"A significant amount of gasoline got into the creek when it shot up and sprayed onto the ground," Ms. Humphreys said. "We've already noted our first fish kill in the creek, and [containment] booms have been deployed by a company working for Sunoco."

Pennsylvania American Water Co., which has a water intake station 20 miles downstream on the Monongahela River, was notified about the leak.

Ms. Humphreys said the DEP was sampling in Turtle Creek. The extent of any fish kill will depend on the amount of flow and turbulence in the creek.

The DEP was providing large fans to clear gasoline vapors from the sewer system.

Mr. Stevens said officials planned to use foam to flush some gasoline through the sewers, sending it to a nearby sewage treatment plant.

Sunoco moved quickly to assist hazardous materials teams and emergency responders, he said.

"We're still determining what happened," said Mark Whalen, a Sunoco maintenance supervisor.

The Eastern Pipeline System of Sunoco Logistics includes approximately 1,747 miles of gasoline pipelines and 140 miles of crude oil pipelines. In the West, it owns about 3,635 miles of crude oil pipelines, mostly in Oklahoma and Texas. It also owns terminal facilities capable of holding almost 9 million barrels of gasoline and 16 million barrels of crude oil.