"We're all interested in seeing what we can do to make sure something like this doesn't happen again," said Gianato.
Following a September 2010 natural gas transmission pipeline explosion that killed 8 people in San Bruno, Calif., the National Transportation Safety Board harshly criticized the emergency response efforts of the pipeline operator, Pacific Gas and Electric Co.
NTSB investigators said in that case that the 95 minutes PG&E took to stop the flow of gas and isolate the ruptured line "was excessively long and contributed to the extent and severity of property damage and increase the life-threatening risks to the residents and emergency responders."
The agency said that the use of either automatic shutoff valves or remote control valves would have reduced the amount of time taken to stop the flow of gas in that incident.
NTSB member Robert Sumwalt said Tuesday night that the Sissonville explosion occurred at 12:41 p.m. and that the flow of gas was stopped at 1:45 p.m., 64 minutes later.
On Wednesday, Chevalier Mayes, communications manager for pipeline operator NiSource Gas Transmission and Storage, declined to describe what sort of shut-off systems the company had in place at the Sissonville pipeline.
Mayes also did not respond to questions about the age of the pipeline and for details of any recent examinations of it by the company.
"Much of the information you inquired about is being assessed as part of the ongoing investigation," Mayes said in an email message. "We'll share more details as we can."
Kanawha County Commission President Kent Carper said he is concerned about the flow of information from NiSource to local emergency responders, especially concerning potential dangers from a second gas transmission line he was told is located in the area of Tuesday's explosion.
"What would have happened if that other line had breached?" Carper said. "It looked like to me the flow of information was a little slow in coming in, but it was a chaotic scene."
Hours after the explosion, respiratory therapist Sancha Adkins was still shaky. She was heading north toward a patient's home in Ripley, a tractor-trailer behind her, when a flash alongside the highway caught her eye.
"And then I just see this whole huge ball of fire, and I'm slamming on the brakes and pulling off to the side of the road, and then the flames come across the road in front of me," she said, still breathless and nearly hysterical hours later. "I saw parts of something - I don't know what it was, a house maybe? - exploding."
A wall of flame roared across the highway about 150 feet in front of her car, she said, and she tried to back up on the shoulder. So did the truck behind her, which was able to stop without rear-ending her vehicle.
"But that wasn't fast enough for me," said Adkins, 36, of St. Albans. "I did a U-turn in the middle of the road and literally drove the wrong way on the interstate. I had my hazard lights on flashing, just trying to tell people to get out of the way."
There was oncoming traffic as she hugged the berm on the median.
"I didn't care," she said. "It wasn't as bad as that explosion."
Adkins traveled about 2 miles, got into an emergency lane and got off at the nearest exit, onto Route 21, still bound for Ripley. Then she realized she was still heading toward the flames.
"I don't think it clicked until then. I was hysterical and crying and flipping out," she said.
She tried to dial 911 three times, she said, but couldn't get the numbers right. Eventually she called her office and told them what happened.
"I'm incredibly lucky I didn't die in a fire," she said as she tried to unwind at a hair salon Tuesday evening.
Kanawha County Metro 911 Director Johnny Rutherford said Metro 911 handled more than 1,650 calls in the three hours following the 1 p.m. gas line explosion and fire. He said the high call volume triggered alarms at Frontier Communications.
Similar high call volumes following superstorm Sandy and the June 29 derecho windstorm caused 911 systems in several states to crash. However, because of upgrades and improvements to the Kanawha County system and a close working relationship with Frontier born out of previous 911 outages, Rutherford said Metro never crashed.
"Our backup systems worked, and 911 was able to keep functioning," he said.