A local firefighter who helps train others in handling hazardous materials said there is a growing concern over the impact oil and gas drilling could leave in Ohio. Youngstown Battalion Chief Sil Caggiano said there are numerous drilling sites across the state, including a couple here in the Valley, where high levels of radium have been detected in the waste coming from the wells. Caggiano said he’s concerned firefighters and other first responders sent to spills or fires involving drilling materials could run into trouble trying to determine what hazards they’re dealing with and how to handle them.