Campagna and his wife, Claudette Lapointe, grabbed their pillboxes and cell phones and fled. The hood of their car was so hot that he couldn’t touch it. (According to Mercier, the heat could be felt for more than a mile.) From a safe distance, about a quarter-mile away, they watched as the town burned. In the early morning hours a steady rain began to fall. The surface of Campagna’s umbrella was so warm that when the drops of water bounced off it they sent spirals of steam into the night. If not for the rain, Campagna says, the whole town would have been destroyed. “The rain saved us,” he says.

Lapointe lost two cousins. Campagna knew everyone who lived in the homes along the lake, some of whom also died. Roger Paquette, a 61-year-old friend of Campagna’s, could not be awoken in time. “Neighbors tried to wake him up, but the back of his house was already on fire,” he says. “All of these people never had a chance to get out of their homes, so swift was the flow of fire.”

Lac-Mégantic residents had little warning they were in danger. Few residents interviewed for this article knew that millions of gallons of highly flammable light crude oil were passing through their lakeside village nearly every day. When it comes to transporting oil by rail, the railroad industry and oil and gas companies operate in near total secrecy, with little federal oversight or regulation to ensure public safety.

The oil moving through Lac-Mégantic was mislabeled – classified as packing group III instead of packing group II or I, which refer to more dangerous substances with lower flashpoints. A hazardous-materials inspection team issued safety warnings in 2011 and 2012, but no changes have been made to tank cars since then. Inspections of loading facilities in the Bakken oil fields conducted in October 2011 and June 2012 found that there were shortages of suitable rail cars; those in use were often being overloaded; and, because of the many different companies involved in transferring and shipping the oil, compliance was difficult to enforce. According to those inspection documents, which were obtained by NBC News shortly after the Lac-Mégantic accident, shippers were regularly using tank cars that did not meet industry specifications. “The pressure to ship those cars was more than the risk of failure in transportation or discovery by FRA [Federal Railroad Administration],” the inspectors noted. They also said the oil was extremely flammable and warned truck drivers and inspectors to take special precautions. “Fire retardant clothing, and grounded equipment, truck and rail cars are mandatory due to the high flammability of the crude and possibility of static discharge.”

The criminal investigation into the accident in Lac-Mégantic, which has focused on the question of whether the brakes were properly secured, was completed in late March. Charges had not been issued, though they were anticipated, when this story went to press.

Even as federal regulators discuss new safety measures – updating or retrofitting the standard petroleum tank cars, reducing train speeds near towns, and performing spot inspections of oil trains – oil trains continue to roll through towns and cities across the United States and Canada. In the last six years the quantity of oil being shipped by rail across North America has increased dramatically. Most of that increase comes from the recently tapped shale oil fields in North Dakota. The Bakken formation is now producing more than one million barrels of crude oil a day, and more than 60 percent of that is shipped by rail. According to the American Association of Railroads, there were 9,500 rail cars carrying crude oil in 2008. Last year there were more than 400,000.

“The Bakken shale has gone from close to nothing to a million barrels a day in a very short time,” Energy Secretary Ernest Moniz told an Albany newspaper in February. “And the infrastructure certainly just isn’t there, certainly in terms of pipelines to manage that.” That means more and more shale oil will be shipped by rail in outdated cars, on tracks that are rarely inspected, and through towns and cities ill equipped to deal with a disaster.

Since the Lac-Mégantic disaster there has been a string of oil train collisions and derailments. Late on the night of November 7, a train carrying at least 2.7 million gallons of Bakken crude derailed near Aliceville, Alabama, resulting in dramatic explosions similar to those seen in Lac-Mégantic. Because the train exploded a few miles outside of Aliceville, no one was injured or killed. On December 30, a train carrying crude collided with another train outside of Casselton, North Dakota, releasing more than 400,000 gallons of oil into the surrounding land. At least half the town’s 2,400 residents were evacuated, though no one was injured. And on April 30, an oil train operated by CSX derailed in the city of Lynchburg, Virginia, sending flames and oil into the James River and forcing the evacuation of more than 300 residents. Last year more oil spilled in rail accidents – 1.15 million gallons – than the previous 35 years combined.

The economic and political pressure to move the oil far exceeds efforts to upgrade the nation’s rail infrastructure and impose new regulations on either the oil or rail industry. Kenton Onstad, a North Dakota legislator who lives just outside New Town, where the train that exploded in Lac-Mégantic originated, says the nation’s oil-by-rail infrastructure needs to be overhauled and that it should have started years ago. According to Onstad, public officials have known since 2009 that the amount of production from the Bakken would be close to what it is today, and yet they did little to prepare for the oil boom. “I think it was economics and profits versus safety,” he says.

“We’ve got all kinds of failings on all sides, inadequacies that are coming to light because trains are blowing up all over the place,” says Fred Millar, a railway safety consultant.

The worries about basic railroad safety are compounded by concerns over the unique composition of Bakken shale oil. Independent tests obtained by Earth Island Journal suggest that the North Dakota light crude is especially flammable, perhaps because it is being produced at such a breakneck pace that drilling companies aren’t following standard industry practices to separate out volatile gases. Each day millions of gallons of highly combustible oil are moving through major metropolitan areas – yet local residents and public officials are often unaware of the danger, and many first responders are unprepared for a disaster like the one that occurred in Quebec.

“I live in fear of waking up to a bunch of text messages and emails because there’s been a 100-car explosion in Chicago and 300,000 people are vaporized,” says Scott Smith, a researcher at the nonprofit group Water Defense and the inventor of Opflex, a foam sponge that absorbs oil and was used in the Gulf Coast after the BP oil spill. “Unfortunately, that is a very real possibility if something’s not done.”

Two weeks before the Casselton collision, Lynn Helms, the director of North Dakota’s Department of Mineral Resources and a chemical engineer, boasted that his agency was prepared to draft a white paper on the properties of Bakken crude “to dispel this myth that it is somehow an explosive, really dangerous thing to have traveling up and down rail lines.” Around the same time an agency spokeswoman was quoted as saying, “Crude is crude.”

Scott Smith knew otherwise. Smith, a citizen-scientist whose work has focused on oil spills, was at home on Cape Cod when he saw images of the fiery explosions in Lac-Mégantic. Having worked on several oil-spill cleanups in the past – including the BP blowout, Italy’s Costa Concordia disaster, and China’s Dalian pipeline explosion in 2010 – he knew this incident was somehow different. According to Smith, when conventional crude oil spills or leaks it rarely goes up in flames. In fact, one method of dealing with offshore oil spills is to try to burn off the oil in the hope that doing so will minimize damage to marine ecosystems. But getting it to burn is often a significant challenge. “Conventional crude on the surface never ever explodes, let alone vaporizes people like Hiroshima,” Smith says. (Five of the 47 people killed in Lac-Mégantic were never found.)

Smith and a pair of colleagues drove up to Lac-Mégantic, where they took samples of the oil from the Chaudiere River. The samples were then tested at an independent lab in Ohio, and later shared with a small group of scientists, including a visiting researcher at Woods Hole Oceanographic Institution. The results showed very high levels of volatile organic compounds (VOCs) present in the oil. Unsatisfied with the lack of information on the characteristics of Bakken crude – and unable to get answers – Smith took a trip to North Dakota and obtained samples of oil from a landowner with an oil well on his property. As he pumped oil out of the ground, Smith says, he could hear the gases escaping. Smith returned to North Dakota after the train collision outside of Casselton and spent 36 hours documenting the spill and taking samples.

Smith now has conducted detailed analyses of Bakken crude from the three accident sites in Quebec, North Dakota, and Alabama, along with baseline data. He says he is the only outside expert to have done so and has shared those lab results with Earth Island Journal. Even government agencies – including the US Department of Transportation (DOT), which is tasked with regulating oil by rail transport – have been largely kept in the dark about the qualities that make Bakken crude so volatile as well as how it varies throughout the formation. “Despite the energy industry making assurances to DOT more than two months ago, we still lack data we requested and that energy stakeholders agreed to produce,” a Department of Transportation spokesperson told Reuters in March.

All the samples collected and tested by Smith share the same high levels of VOCs and alkane gases in what Smith says are exceptional combinations. According to Smith, 30 to 40 percent of Bakken crude is made up of toxic and explosive gases. Typically these gases are separated out of the crude oil before transport. A recent report by the Pulitzer Prize-winning website Inside Climate News speculates that because of the whirlwind pace of production in North Dakota and the absence of processing facilities, volatile gases like propane are not being removed at the wellhead.

There’s still a lot we don’t know about Bakken crude, Smith says. This includes the presence of metals, radioactive materials, and gases. Because of the varying depths of the Bakken formation, two wells a mile apart can produce crude oil with very different characteristics. This makes sampling and testing especially tricky. It also makes industry cooperation essential.

Smith still has vials of Bakken crude that he pumped out of the ground nearly a year ago. “When it gets above 80 degrees and you shake them,” he says, “it bends the top of the container. Any form of static electricity will ignite this stuff and blow it up.”

Independent reviews corroborate Smith’s findings. Chemists with California’s Office of Spill Prevention and Response examined Smith’s samples and concluded that the Bakken crude “resembles a typical crude oil that has been mixed with diesel or a diesel/gasoline mix. … Obviously, flammability and volatility are greater concerns with Bakken than with ‘typical’ heavier crudes.” In February The Wall Street Journal, based on its own analysis of data collected by the Capline Pipeline in Louisiana, reported that oil coming from the Bakken has significantly more combustible gases and a higher vapor pressure than oil from other formations. In early March, Canada’s Transportation Safety Board (TSB) issued its own findings from oil samples taken from the nine tank cars that did not derail in Lac-Mégantic. While the TSB does not contend, as Smith does, that the Bakken oil is significantly different from other light sweet crudes, the agency also found that oil coming out of the Bakken has a very low flashpoint – which means that it ignites easily or at a relatively low temperature – a level more similar to unleaded gasoline. When the rail cars went off the track in Lac-Mégantic, sending up sparks and static charges, it didn’t take much to set off explosions. “All of the conditions required for ignition to occur were present,” the TSB report concluded.

Yet little, if any, of this information would have been available to local officials or emergency responders in Lac-Mégantic. Material Safety Data Sheets contained contradictory information about the flammability of the oil onboard the train. According to a lawsuit filed by track owner Montreal, Maine & Atlantic, the shipping documents it was given stated that the oil had high flash and boiling points. The company says that if it had known of the oil’s volatility, it “would have implemented safety procedures and protocols that would have prevented the derailment.”

Even the US government appears to be scrambling to understand precisely what makes the Bakken crude so dangerous. According to The Wall Street Journal, federal regulators seeking information about the flammability of Bakken crude have been rebuffed by the oil industry. When asked to respond to findings that Bakken crude may be especially volatile, a North Dakota Department of Mineral Resources spokeswoman, Alison Ritter, wrote in an email: “We do not have the expertise to analyze Bakken crude. Crude samples are submitted to us for possible third party analysis. It would be up to that independent analysis to make the determination as to the volatility.” Only in late March did the North Dakota Petroleum Council, an industry trade group, announce that it would be doing its own analysis of Bakken crude across 12 sites and six rail depots.

“For some reason this entire rail oil industry, they just fill these rail cars and send them without really knowing what’s in them,” Smith says. “And it’s the only industry I’m aware of that gets away with that.”

A map of the nation’s freight rail network looks like a diagram of the circulatory system, its 140,000 rail miles the blood vessels and capillaries connecting major cities to ports and refineries. At its heart is Chicago, which has more lines of track extending out than any other city. More than 500 freight trains and 800 passenger trains pass through the city every day. From there everything flows. Through Kansas and Oklahoma City to the Gulf Coast, where Kinder Morgan has plans to complete a 210,000-barrel-per-day rail terminal in Houston. Through Cleveland and Buffalo to ports on the Hudson and refineries in Philadelphia, New Jersey, and Delaware. North through Montreal to the Irving Oil Refinery in New Brunswick, where the train that leveled Lac-Mégantic was destined. Every day oil trains carrying up to 85,000 barrels of oil arrive in Albany, a city of about 100,000 people. A refinery in Philadelphia receives one-fifth of all oil produced in the Bakken and has plans to expand production and rail capacity. In January, an oil train derailed while crossing a bridge over the Schuylkill River, though no oil spilled. Other trains carrying Bakken crude move west from North Dakota to Washington, Oregon, and California.

For the oil industry the location of the Bakken is a blessing and a curse. It’s close to the Chicago hub, but about as far from ports and refineries as possible. This means the oil has to travel long distances, in some cases thousands of miles, and is subject to fluctuations in temperature and pressure, a factor that Smith says can contribute to its volatility. As temperatures rise, the oil warms and expands. As the rail cars move and shake, volatile compounds like propane and butane can separate from the oil and rise to the surface, collecting in the headspace above the liquid petroleum. A small puncture, leak, or derailment accompanied by a static charge or spark can set off an explosion.

In the United States freight railroads are privately owned and the companies that operate them are responsible for track maintenance and upkeep. According to the General Accounting Office, the Federal Railroad Administration (FRA) is able to inspect only two-tenths of one percent of the railroads’ operations each year. “So the ability to inspect the track regularly is impossible,” says Larry Mann, a rail safety lawyer who also serves on the FRA’s Rail Safety Advisory Committee. “And some areas of track are probably never inspected.”

In addition, most of the oil being transported from the Bakken is being shipped in DOT 111 tanker cars that have long been acknowledged as inadequate for transporting hazardous materials. A 1991 National Transportation Safety Board report stated: “The inadequacy of the protection provided by DOT 111A tank cars for certain dangerous products has been evident for many years in accidents investigated by the Safety Board.” Sometimes referred to as Pepsi-cans on wheels, the DOT 111 has a very thin shell – between a quarter- and a half-inch thick – and no head shields to prevent the cars from being punctured in case of a derailment. Yet there are still at least 228,000 DOT 111s on the rails; the industry has no choice but to use them or stop shipping Bakken crude. According to Mann, “It’s going to be quite a while before these cars are weeded out.”

Meanwhile, trains carrying Bakken crude continue to pass through major cities, small towns, and national parks. The Chicago-Indiana corridor is one example. Densely populated parts of the Northeast – including Philadelphia, Albany, and Buffalo – are another. “The most essential risk reduction factor of all is distance,” railway safety consultant Fred Millar says. “You don’t put a liquefied natural gas plant in the middle of a city. You don’t put a nuclear plant in the middle of city. In this case they [the railroads] say ‘the hell with it. Our property goes through your city,’ and they bring those risks right into our cities.”

They do so without the public and, in many cases, emergency response teams knowing. Railroads are not required to publicly disclose when and where they ship their freight. (In the wake of recent accidents, some railways have provided limited information to emergency response teams and local officials). They also have vigorously resisted efforts to force them to reroute hazardous material around densely populated areas. In 2005, Washington, DC passed an ordinance forcing CSX to reroute hazardous materials around the downtown. But the rail industry sued, then lobbied for passage of a federal bill that would preempt local control, essentially nullifying the DC ordinance. In 2007, Congress passed and President Bush signed an industry-friendly bill that allows the railroads to make routing decisions without public disclosure.

“Because of security issues the routing is confidential,” Mann says. “We don’t know the extent to which there is rerouting. And if there is rerouting we don’t know where it’s being rerouted.”

Lack of information regarding the oil itself and its whereabouts can be multiplied across hundreds of towns and cities in North America. Randy Sawyer, the chief environmental health and hazardous materials officer for Contra Costa County in California, says the rail companies haven’t shared any information with his agency about when and where the oil will be moving. In the coming year, California expects to receive at least six oil trains per day, each carrying approximately 2.7 million gallons of crude oil, an increasing amount of it from the Bakken. Much of that could pass through Contra Costa County, which is home to four refineries and more than one million residents.

Sawyer says that, at a minimum, local officials need to know when and how often these trains will be arriving. Asked if his division is prepared to respond to a derailment like the one that occurred in Lac-Mégantic, he said: “I don’t know if anybody’s really prepared for something like that, to tell you the truth. That was a big, big fire.”

On the opposite coast, the mayor of Haverstraw, New York, Mike Kohut, is in a similar situation. About a year ago, CSX, which operates the rail line that passes through some of the Northeast’s most densely populated areas, held a meeting with local officials in Orange County and Rockland County. According to Kohut, CSX employees said they would be upgrading two railroad crossings in downtown Haverstraw to accommodate more train traffic. But they didn’t say why and he doesn’t recall any mention of Bakken crude oil. Since then, Kohut hasn’t received any information from CSX about shipments of Bakken crude. Kohut, who is also a member of the volunteer fire department, says: “Everyone would like to have more information on if it derails and the liquid is moving what you have to do. Do you really need to evacuate the entire town? What kind of precautions have to be taken, and at what distance?”

In a written statement CSX said the company works with emergency responders “across its network” to make sure they “have access to information about materials moving on the rail network should the need arise.” In addition CSX shares information through a program called SecureNOW, which gives “security officials and first responders the ability to track, in nearly real time, the location of CSX trains and their contents.”

However, interviews with local emergency response officials in Virginia, where a CSX train derailed in late April, suggest that the company’s outreach efforts vary widely. According to Ryan Muterspaugh, director of public safety in Alleghany County, the railways do not supply information on volume, content, or frequency of rail cars with any regularity. “The railways are not as forthcoming with their transportation information as we (or anyone) would probably like them to be,” he wrote in an email. “Our emergency management personnel or fire/rescue agencies have not had any interaction with the railroad specifically regarding the transportation of crude oil.” Gary Roakes, the fire marshal of Amherst County, which borders the city of Lynchburg, wrote: “We have not had any contact with CSX or any other carrier about what is being shipped through this area.” Kohut says he has never heard of SecureNOW.

The Pipeline and Hazardous Materials Safety Administration issued its first safety alert involving Bakken crude in early January. It warned first responders that Bakken crude “may be more flammable than traditional heavy crude oil.”

As this story went to press, the investigation into the Aliceville, Alabama explosion in November 2013 was still ongoing. An accident report submitted to the FRA by rail line company Genesee & Wyoming at the end of December stated: “Cause of derailment has not been determined.” The investigation could take several more months.

According to Genesee & Wyoming, the rails had been inspected just four days before the accident and, over the past year, had received a “disproportionately high” level of investment. “There was no concern about the state of the track,” the company’s CEO told Reuters. The company also noted that the train was going slower than the 40 mph speed limit. In addition, it’s a straight section of track on flat ground. Had the explosion occurred a few miles up the track, it would have ripped through the small town of Aliceville, which has a population of about 2,500. The same goes for the Casselton collision, which occurred a mile from the center of town. Local officials, fire departments, and emergency responders had very little to go on. “We had no idea it was this volatile,” Casselton fire chief Tim McLean told a local paper.

“These guys have to step up,” says Haverstraw Mayor Mike Kohut, referring to the oil and rail industries. “The railroads have to redesign these tankers to make them safer. And the oil industry has to partner with them, whether it’s in the training of emergency responders or in helping them upgrade the cars. I think there’s enough money being made that somebody ought to be helping the local communities that could suffer these potentially devastating side effects.”

Meanwhile, information about Bakken crude, the trains carrying it, and its impact on the environment in the event of a spill will continue to come from citizen watchdogs. Five days after the Alabama explosion, Scott Smith tried to access the crash site along with John Wathen, a member of the Waterkeeper Alliance and a Hurricane River Creekkeeper for Friends of Hurricane Creek, an Alabama conservation group. A private security guard working for Genesee & Wyoming told them that the location was off limits and that the FBI and FRA were conducting an investigation. They were also told by the guard that the “mess” had been contained.

The following day Wathen and South Wings, a conservation group that uses small aircraft to evaluate the environmental impacts of oil spills and other disasters, flew over the area. They were immediately able to identify the location of the spill and could see rainbow colored slicks a quarter-mile from the crash site leading into Lubbub Creek, which eventually flows into the Tombigbee River. The wetland surrounding the railroad track was filled with oil. Wathen says he spotted emergency workers standing waist deep in crude spraying with high-pressure hoses to disperse the oil.

After the flyover, Wathen returned several times to monitor the cleanup. Eleven weeks later he was still able to place a quart container next to the tracks and fill it with Bakken crude. There were few signs of life, Wathen says. Most of the trees and plants –cypress, tupelo, and black gum – had been burned, and the water was still laced with oil.

Wathen says he has plans to go back to North Dakota with Smith later this year so they can test the soil when the ground thaws. Before Aliceville he knew nothing about Bakken crude. “Now,” he says, “I’m fascinated. Horrified but fascinated by this oil. What in the world have we unearthed up there?”