( CNN ) -- Some 5,000 residents in eastern Pennsylvania were allowed to return to their homes Saturday afternoon , some 12 hours after they were evacuated when a tractor-trailer carrying 33,000 pounds of toxic hydrofluoric acid overturned after the driver tried to avoid a deer , authorities said . Traffic is backed up Saturday after a truck spilled hydrofluoric acid in eastern Pennsylvania . State police identified the driver as Raymond Leblanc , 54 , of Harrow , Ontario , Canada . Leblanc , who initially was trapped in the truck , was taken to a hospital where he was treated and released . Police said a passenger in the truck was unhurt . No other injuries were reported . The truck flipped over on its side and slid along northbound State Road 33 , which was closed in both directions from Belfast to Saylorsburg , Pennsylvania , from the time of the early-morning accident until about 6 p.m. Saturday . Most of the acid in the tank was in the form of pressurized gas , but there also was some water , said Northampton County spokesman John Conklin . State and federal hazardous materials experts stopped the leak by noon . The wreck occurred at 3:30 a.m. near Wind Gap . Conklin said many evacuees -- those living within a mile of the accident site in Plainfield Township -- went to a shelter set up at nearby Pen Argyl High School in Pen Argyl , Pennsylvania . A dispatcher with the Northhampton County Division of Emergency Management said residents were allowed to begin returning to their homes about 3:45 p.m. Saturday . Hydrogen fluoride is a hazardous chemical compound used mainly for industrial purposes such as etching glass , and is extremely corrosive . It also is an ingredient in high-octane gasoline , refrigerants , aluminum and light bulbs . Contact with concentrated solutions can cause severe burns , according to medical authorities . Inhaling the gas causes respiratory irritation , severe eye damage and pulmonary edema .
5,000 evacuees able to go home 12 hours after evacuated because of acid spill . Canadian driver tried to avoid hitting a deer , flipped tractor-trailer . Leak of highly corrosive hydrofluoric acid stopped .