Days after the Feb. 16 derailment of a CSX Corp. (NYSE: CSX) train in West Virginia, which caused several explosions and 19 of the train’s 107 CPC-1232 model oil tank cars to catch on fire, the cause of the derailment remains unknown, according to a statement from the U.S. Coast Guard.

The Associated Press reported that the train was transporting 3 million gallons, or about 71,000 barrels, of crude oil from North Dakota to Yorktown, Va. A total of 27 tank cars derailed during the incident. Area residents were evacuated from their homes after the derailment.

However, investigators ruled out the possibility that the train was traveling too fast. According to the New York Times, U.S. Department of Transportation (DOT) confirmed that the stretch of track where the train derailed had a speed limit of 50 mph while the train’s speed was 33 mph.

In the meantime, cleanup and recovery efforts continue near Mount Carbon on the Kanawha River. CSX, in cooperation with federal, state and local officials, began re-railing cars that derailed but were not damaged during the subsequent fires. As of Feb. 19, six cars had been re-railed. CSX also began transferring oil out of the damaged cars for removal from the site.

To allow for a unified response to the derailment, the West Virginia Train Derailment Unified Command was established by the Coast Guard, DOT, Environmental Protection Agency, CSX, the West Virginia Environmental Protection and Military Affairs & Public Safety departments, including the National Guard, West Virginia Department of Environmental Protection and local agencies. According to Coast Guard Capt. Lee Boone, federal on-scene coordinator for the derailment response group, the major priorities during the recovery effort are “the safety of the community and responders, and mitigating the impact to the environment.” One person was treated for possible respiratory problems, and no other injuries were reported.

While at least one small fire continued to burn overnight on Feb. 18, efforts to prevent damage to the local environment were already underway. Though some early reports of the derailment claimed that some of the derailed tank cars may have entered and possibly contaminated the Kanawha River, which is adjacent to the rail, the Coast Guard confirmed in a statement that no cars entered the river. Following the incident, response teams were ordered to deploy about 500 feet of containment boom as a precautionary measure to prevent a possible spill into the river. Monitoring of the air and water quality is continuing, with no impact to either found so far.

With no environmental impact detected, the Unified Command said Feb. 20 that residents from two nearby communities could return to their homes. Residents from a third community were allowed to return home on Feb. 19. Only residents of five homes near the site have not yet been able to return home.

“After careful evaluation, we have determined it is safe to reopen one lane of Highway 61 and allow residents to return to their homes,” said Dennis Matlock, federal on-scene coordinator. “Safety of the residents remains our top priority. We encourage residents and drivers to continue to exercise caution when travelling through the area.”

Contact the author, Caryn Livingston, at clivingston@hartenergy.com.