"The cause of the derailment is under investigation by the company and officials of the Federal Railroad Administration," according to CSX.
"The EPA has two of its on-scene coordinators and contractor support on scene assisting the state and local responders with air monitoring support and water quality monitoring," according to a statement Thursday afternoon from the Atlanta office. "Culton Creek is located in close proximity to the derailment site. Additional EPA staff are en route to help facilitate 24-hour response operations."
According to the EPA, it is conducting "roving air" monitoring activities around the evacuation zone.
"The EPA is also deploying an air monitoring array and will conduct water quality sampling as necessary. The EPA has also requested assistance with health and safety oversight from the U.S. Coast Guard Gulf Strike Team," according to the agency's statement.