MOUNT CARBON, W.Va. — Oil cars were still burning more than a day after a train carrying 3 million gallons of North Dakota crude derailed in a West Virginia snowstorm, shooting fireballs into the sky.

Hundreds of families were evacuated after losing their drinking water and electricity when 19 tanker cars slammed into each other and caught fire, leaking oil into a Kanawha River tributary and burning a nearby house down to its foundation.

“There’s nothing there,” said Democratic U.S. Sen. Joe Manchin, who toured the scene. “All you can see is a couple of blocks sticking out of the ground. There’s some pickup trucks out front completely burned to the ground.”

One person – the homeowner – was treated for smoke inhalation, but no other injuries were reported, according to the train company, CSX. The two-person crew, an engineer and a conductor, managed to decouple the train’s engines from the wreck behind it and walk away unharmed.

The train derailed near unincorporated Mount Carbon just after passing through Montgomery, a town of 1,946, on a stretch where the rails wind past businesses and homes crowded between the water and the steep, tree-covered hills.

Fire crews had little choice Tuesday but to let the tanks burn themselves out. Each carries up to 30,000 gallons of crude.

These rail shipments jumped from 9,500 carloads in 2008 to more than 435,000 in 2013, driven by a boom in the Bakken oil patch of North Dakota and Montana, where pipeline limitations force 70 percent of the crude to move by rail, according to American Fuel and Petrochemical Manufacturers.

The downside: Trains hauling Bakken-region oil have been involved in major accidents in Virginia, North Dakota, Oklahoma and Alabama, and Canada, where 47 people were killed by an explosive derailment in 2013 in Lac-Megantic, Quebec.

Reports of leaks and other oil releases from tank cars are up as well, from 12 in 2008 to 186 last year, according to Department of Transportation records reviewed by The Associated Press.

Just Saturday – two days before the West Virginia wreck – 29 cars of a 100-car Canadian National Railway train carrying diluted bitumen crude derailed in a remote area 50 miles south of Timmins, Ontario, spilling oil and catching fire. That train was headed from Alberta to Eastern Canada.

The train that derailed Monday was bound for an oil shipping depot in Yorktown, Virginia along the same route where three tanker cars plunged into the James River in Lynchburg, Va., prompting an evacuation last year.

All three of these accidents involved model 1232 tank cars, which include safety upgrades voluntarily adopted by the industry four years ago. An estimated $7 billion has been spent to put 57,000 of these cars into service, according to the Railway Supply Institute.

Now the Obama Administration is considering requiring even more upgrades, such as thicker tanks, shields to prevent tankers from crumpling, rollover protections and electronic brakes that could make cars stop simultaneously, rather than slam into each other.

Some of these measures would cost billions more and have been strongly opposed by the oil and rail industries.

The National Transportation Safety Board said its investigators will compare this wreck to others including Lynchburg and one near Casselton, N.D., when a Bakken crude train created a huge fireball that forced the evacuation of the farming town.

“This accident is another reminder of the need to improve the safety of transporting hazardous materials by rail,” said Christopher Hart, NTSB’s acting chairman.

Snow was falling heavily Monday – as much as 7 inches in some places – but it’s not clear if weather was a factor. All but two of the 109 cars were tankers, and 26 of them left the tracks.

No cause has been determined, said CSX regional vice president Randy Cheetham. He said the tracks had been inspected just three days before the wreck.

“They’ll look at train handling, look at the track, look at the cars. But until they get in there and do their investigation, it’s unwise to do any type of speculation,” he said.

By Tuesday evening, power crews were restoring electricity, water treatment plants were going back online, and most of the local residents were back home. Initial tests showed no crude near water plant intake points, state Environmental Protection spokeswoman Kelley Gillenwater said.

If approved, the increased safety requirements now under White House review would phase out tens of thousands of the older tank cars being used to carry highly flammable liquids, and require more recently retrofitted cars to have new upgrades.

Sen. Manchin and Gov. Earl Ray Tomblin deferred questions on safety Tuesday, saying it’s largely up to federal officials. But the state does have a say over some safety variables, such as public disclosure.

Railroads are required by federal order to tell state emergency officials where trains carrying Bakken crude are traveling. CSX and other railroads called this information proprietary, but more than 20 states rejected the industry’s argument, informing the public as well as first-responders about the crude moving through their communities.

West Virginia is among those keeping it secret. State officials responded to an AP Freedom of Information request by releasing documents redacted to remove nearly every detail.

There are no plans to reconsider after this latest derailment, said Melissa Cross, a program manager for the West Virginia Division of Homeland Security and Emergency Management.