Natural gas venting prompts brief OR evacuation
Wednesday, August 31, 2011
HILLSBORO, Ore. (AP) -- A Hillsboro Fire and Rescue spokesman says crews briefly evacuated homes in a three-block area of the Portland suburb after a Northwest Natural Gas relief valve was triggered and began venting natural gas into the air.
Spokesman Storm Smith says residents began calling 911 Wednesday afternoon when they smelled the odor of mercaptan, a chemical that the utility adds to the natural gas to give it a distinctive odor so leaks can be detected.
Smith says the relief valve performed properly in response to an overpressure situation in a gas line. The valve closed about two hours after the incident began. Smith says nearby homes were checked for gas and residents were allowed to return.