People who were forced to flee after a toxic chemical spill in Clearfield County last night are returning to their homes and businesses. Late Thursday night, a truck carrying a toxic chemical began to leak on the off-ramp at Interstate 80 exit 97. The leaking chemical sent a toxic gas cloud into the air, causing crews to close all local roads within a mile of the exit and a 38-mile section of Interstate 80.

It all started when the driver of the truck carrying silicon tetrachloride noticed a leak. A truck company representative said the driver noticed the leak at a Pilot Travel Center. He then drove the truck a mile down the road away from area businesses and possible human exposure to harmful gases. Officials say a valve malfunction caused the leak.

Spill clean-up was a coordinated effort of 20 agencies. The Hazmat Shark Team was in full-body protective gear heading out to the spill to keep it from spreading. Dow Corning Company crews from, Midland, Michigan also responded.

While cleaning up, crews redirected the west-bound detour off Exit 111 at Penfield, down State Route 153, then west on State Route 322, 40 miles to Brookville, and, the opposite for eastbound traffic. However, all roads that had been closed due to the spill have reopened.

Between 250 and 300 residents from Falls Creek, the Singing Hills area and even a Holiday Inn were forced to leave and find shelter elsewhere. Many found shelter at the 3rd Ward Hose Company in Dubois and the Brockway Fire Hall.

Silicone tetrachloride, the chemical that spilled, is used in the electronics industry to make silicon wafers for computers. Military personnel use it to make smokescreens. It is also used to analyze other metals. When mixed with water, it turns into hydrochloric acid and can burn skin on contact. Inhaling can cause a burning feeling in the lungs and continued exposure can result in death.