Federal investigators on Thursday reconstructed the scene of this week's collision between a CSX cargo train and a truck, hoping to piece together more information on the derailment and explosion that rocked businesses and homes in the Rosedale area.

Crews with the National Transportation Safety Board plan to stay in Baltimore County for several more days before heading back to their headquarters in Washington to continue their probe of Tuesday's crash, according to board member Robert Sumwalt.

Sumwalt said investigators felt they needed to reconstruct the crash scene as soon as possible. The exercise will help them determine at what point the truck, driven by John Alban Jr., may have been visible to the train crew, and vice versa.

Officials said they will eventually scrutinize numerous records as part of the investigation — including cellphone records of the train crew and Alban, as well as the safety record of Alban's company, Alban Waste LLC. For now, though, the focus is on gathering evidence that could disappear once the tracks reopen, Sumwalt said.

"We are here on scene to collect the perishable information," he said. "Our priority is to get out there and document those things that will go away with the passage of time."

Investigators have obtained a blood sample from Alban and will seek results of drug and alcohol testing, which is protocol in all accidents reviewed by the board, Sumwalt said.

The three members of the train crew were not tested for drugs or alcohol, according to CSX spokesman Gary Sease.

He said in an email that CSX employees are subject to federal regulations on random drug and alcohol testing, but "this incident was not among those circumstances" that require testing.

The 45-car train with two locomotives was on its way to Waycross, Ga., from Albany, N.Y. Fifteen cars derailed in the incident, including three carrying hazardous materials. Investigators believe it was sodium chlorate that exploded. The blast shattered windows and cracked foundations in the neighborhood near the crash.

Sumwalt said the safety board has no estimate of the total cost of damage in the community, but received estimates from CSX on damage to its own property. The company believes damage to the track totals $120,000, with damage to equipment estimated at $505,000, he said.

The company has not yet determined the cost of environmental cleanup, Sumwalt said.

The derailed cars have been moved from the Rosedale tracks and will be taken to a rail yard in Baltimore, where workers will determine whether they can be repaired, Sease said.

Also on Thursday, investigators conducted a post-crash inspection of the truck, examining its brakes and other components. They also began interviews of the train crew members, who live in Virginia.

They have not been able to interview Alban, who remains hospitalized, Sumwalt said.

Officials are asking for the public's help in obtaining footage of the accident.

"The video that people have taken from cellphones and other means, that is very important to us," Sumwalt said, though he added that images of the explosion taken from miles away would not be as helpful as footage of the crash itself.

People can send video or other information to witness@ntsb.gov.

alisonk@baltsun.com

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