In the northern suburbs of New York City, endless strings of black tanker cars have become commonplace sightings at railroad crossings. They move along briskly with red hazmat placards reading “1267” — indicating crude oil — affixed to them. And while the rail and oil industries assure the public that these “virtual pipelines” are not much of a hazard, they're behemoths of kinetic energy flush with vast amounts of potential, explosive energy. An impact with a tanker car can spark a catastrophic detonation, annihilating whatever is nearby.

One such explosion occurred last summer in Lac-MÃ©gantic, Quebec, a tiny lakeside village of less than 6,000 people. On July 6, a 74-car train carrying Bakken formation crude oil ran away and derailed, resulting in a massive explosion of multiple tanker cars. The blast radius was more than a half mile in diameter. Forty-seven people were killed, and 30 buildings — about half the village's downtown — were leveled.

The Lac-MÃ©gantic train was destined for the same New Brunswick refinery that is sometimes the destination of the oil that travels through the Hudson Valley counties of Rockland, Orange, Ulster, and Greene. Other trains in those Hudson Valley communities go to refineries along the U.S. East Coast.

Besides explosions, there have been several significant spills across the U.S. in the past six years. Together, these events have spilled more than 3 million gallons of oil, polluting wetlands, aquifers and residential areas, and the spills are not always cleaned up adequately, if at all. What's even more unsettling is that the volume of crude oil moving through the country by rail increases unabated, raising the odds of more tragedies in the future.

In six short years, the number of rail cars loaded with crude oil has increased 40-fold, and industry analysts predict that the amount of oil-by-rail will quadruple over the next decade. Oil-by-rail shipments through densely populated areas including suburban New York, Philadelphia, New Orleans, Albany, NY, Minneapolis, Chicago, Cleveland and Buffalo, are expected to increase significantly.

The shale oil boom has gained momentum with the rise in global oil prices. Horizontal drilling and hydraulic fracturing, once considered expensive extraction technologies are now relatively affordable for the oil industry. But the boom has not been accompanied with a corresponding expansion and upgrade of our nation's transportation infrastructure. Oil production often comes from fields that don't have direct access to waterways and pipelines. Constructing new pipelines or converting the existing lines pose headaches for engineers, as this viscous, highly corrosive crude needs great amounts of pressure to push through systems without compromising them.

The rapid growth in Albany and the region to its south is of particular concern to local environmental groups. With little public awareness and input, the Port of Albany oil terminals are quietly expanding capacity to accept crude oil shipments by rail for transfer to river vessels. They are now permitted to handle 2.8 billion gallons per year, but the expansion means much more crude oil will travel through the Lower Hudson Valley.

The oil moving through the area is often the same Bakken crude from the shale formation located beneath Montana, North Dakota, Saskatchewan and Manitoba. Production rates are estimated to be nearly 500,000 barrels per day, and crude oil is shipped via rail to refineries located throughout Canada and the United States. While oil-by-rail has increased six-fold since 2011, according to American Association of Railroads, shipments from the Bakken region have jumped exponentially in that time. This great increase in oil-by-rail has been devastating to the environment. Fully loaded “unit trains” are made up of 75-100 tanker cars carrying about 30,000 gallons each, and last year alone, more than 1.15 million gallons of oil were spilled from them in rail accidents and derailments, which is greater than the four previous decades combined.

But what makes the rail transportation of Bakken crude notable is its particular instability due to high levels of gases and volatile organic compounds trapped in the mix. "Large amounts of vapor pressure can split the tank, sink the roof and emit (a) flammable gas cloud," the Canadian Crude Quality Technical Association, an industry-sponsored research group, said in March. Also in question are the high amount of corrosives found in the fuel, which may affect the integrity of tanker cars. Oil producers in the Bakken region have reported large amounts of corrosion in tank cars and "high vapor pressure causing bubbling crude."

Yet it took another disastrous rail-car explosion in Casselton, ND (population 2,470) last December for federal regulators to finally take notice. A week later, they issued a safety advisory regarding the rail shipment of Bakken crude.

Not only is this crude uniquely explosive and corrosive, the DOT-111 rail cars that carry it have their own safety issues, including a tendency to rupture on impact, which makes them dangerously incompatible for the shipment of such a volatile cargo.

National Transportation Safety Board chairperson Deborah Hersman is considering requiring safety upgrades to the 92,000 existing DOT-111s and New York Senator Chuck Schumer requested that this class of rail cars be phased out altogether. The Association of American Railroads has reported that only some 15% DOT-111 cars in use even meet current standards, and those that do may still require safety upgrades.

Along with evidence that the DOT-111s are unsafe, federal regulators have also discovered that oil companies have regularly misclassified Bakken crude to make it appear less risky to the public than it actually is. In response, the Department of Transportation is now requiring companies moving crude oil by rail to test the volatility of fuel out of the Bakken fields before it is put in tanker cars.

The department said in a statement it "issued an Emergency Order requiring all shippers to test product from the Bakken region to ensure the proper classification of crude oil before it is transported by rail." Some of the more volatile crude oil — categorized as less flammable Group III products — must now be labeled as Group I or Group II, which require “more robust” cars. But the order does not necessarily ban the DOT-111s.

The department has also asked the oil and railroad industries to come up with voluntary changes in the way oil is transported to increase safety. But asking industries to self-regulate is not a reliable way to assure safety.

In response to DOT statements, the railway industry has given little more than lip service. Jack Koraleski, CEO of Union Pacific Railroad, told the Associated Press the industry plans to begin treating crude oil like a hazardous chemical and carefully plan out the safest routes possible using existing federal rules. Also, in a document recently obtained by the AP, the Association of American Railroads informed the DOT that it would take on a “wide-ranging voluntary safety measures” for trains carrying crude oil, including slowing down in densely populated areas, more thorough track inspection, and ramping up emergency response planning. The document did not indicate how these changes would be enforced.

While they might sound substantive, these measures may not go far enough. The oil producers have grossly miscalculated the volatility of crude in the past. What assurances does the public have that they've changed their ways? Even if retrofitted, there are no guarantees that DOT-111s would become impact-proof and impervious to the corrosive qualities of Bakken crude. Rerouting around high-population areas might not be feasible, as transportation regulations rely on many factors to determine routes for hazardous shipments; once they're all factored in, some oil-by-rail shipments might not be rerouted at all.

This brings us back to the Hudson Valley, where an expansion of crude-oil transportation is on the horizon. Global Partners, a major petroleum distributor in the region, already has the capacity to offload two trains of unrefined oil to river vessels daily, a transfer that can be up to 5 million gallons of Bakken crude. Now, Global Partners wants to expand its “virtual pipeline” by adding a thick, heavy crude oil — possibly from the Alberta tar sands — to the mix. This would greatly increase the number of trains and barges traveling through the valley and on the Hudson River.

Also as part of this expansion, Global Partners wants to install up to seven boilers to heat train cars containing the thicker crude. Global Partners claims this will help the tar-like substance flow while being transferred from train cars to barges for river transport.

Global Partners' plan will no doubt increase the amount of oil-by-rail traffic through the Lower Hudson Valley. But in the short time since oil-by-rail first expanded a few years back, the region already has had two close calls.

Last November, a car-carrier collided into a train hauling empty oil-tanker cars in the New York City suburb of Clarkstown, NY (population 84,187). The site of the collision, the hamlet of West Nyack, is a moderately populated area with several schools, one of the nation's largest shopping malls, and a reservoir system that provides water to Rockland County's 320,000 residents and also feeds into the Bergen County, NJ watershed. Had the tanker car been filled, it could have been a catastrophe, not only to the immediate area, but possibly to the regional transportation and water infrastructure.

And just this week, a train carrying nearly 97 empty DOT-111 tanker cars derailed near Kingston (population 24,000), in Ulster County. The train was traveling on the same track that runs through Rockland and Orange Counties.

Local governments and media have allowed residents in the Lower Hudson Valley to remain blissfully ignorant of the potential calamity. Coverage by local news outlets has been all but nonexistent, and the four Lower Hudson Valley counties have not publicly disseminated public-safety alerts, emergency preparedness plans, or evacuation plans for potential rail disasters. A spokesperson for Rockland County's Department of Fire and Emergency Services said that the county is reviewing its emergency response protocols with the crude-oil shipments in mind.

To their credit, local, state and federal officials, and first responders have begun to hold spill exercises in the region. The first drill, held last year Orange County, simulated a non-explosive spill of 50,000 gallons of heating oil from a five-million gallon storage tank into the Hudson River. In the scenario, the spill derailed a nearby CSX train. But the drill, co-hosted by Global Companies, a subsidiary of Global Partners, was in no way a preparation for an explosion involving a full assemblage of tanker cars brimming with Bakken crude.

The Casselton and Lac-MÃ©gantic explosions did get the attention of New York Governor Andrew Cuomo. Late last month, he issued an executive order identifying many of the immediate risks in the transportation of crude oil. As part of the order, Cuomo directed five state agencies to report on the state’s preparedness to handle a crude oil spill or fire. Cuomo also called for federal agencies to strengthen regulations for transportation of unrefined petroleum products.

Unfortunately, like the rail industry's list of oil-by-rail modifications, Cuomo's executive order does not bring about any actual or immediate changes to mitigate the risks of oil-by-rail. Meanwhile, the expansion of this virtual oil pipeline continues through New York communities at a brisk pace.

UPDATE: Hours after we broke this story, the Journal News, a newspaper serving the Lower Hudson Valley, reported that Rockland County Officials are beginning to take action. The Sheriff's Office is now using radar guns to check speeds of CSX trains running through the county and has requested that the railroad to provide local officials with a daily list of the hazardous materials aboard the trains. On March 1, it was also reported that New York State and federal authorities have begun inspecting facilities used to ship oil-by-rail in the state, including sites in Buffalo and Albany, as well as the rail tracks and the tank cars that carry the crude.