A second fiery derailment near a Northern Ontario community is adding to concerns that federal rail-safety regulations – brought into effect after the 2013 tragedy in Lac-Mégantic – do not go far enough in addressing the dangers of shipping crude oil by rail.

The accident, which occurred early Saturday morning, marks the second time in less than a month that a Canadian National Railway train carrying crude oil has derailed and caught fire near the community of Gogama, Ont. Between 30 and 40 tank cars went off the tracks less than four kilometres from Gogama, about 100 kilometres south of Timmins, causing a massive blaze that was still burning Sunday afternoon.

Several tank cars are in the nearby Makami River and police warned residents to stay indoors on Sunday amid fears about possible air and water contamination.

Gerry Talbot, secretary of the local services board, said the recent accidents raise questions about current safety standards and called on the government and CN to look at the issue more closely.

“We need answers,” Mr. Talbot said in an interview on Sunday. “You know, why is it happening? People are asking these questions. Is it because the trains are heavier? The trains are certainly longer. Is it because the cars, the tanker cars, are not built strong enough to withstand the impacts?”

The tank cars involved in both of the accidents near Gogama were CPC-1232 models, according to CN. Those models have steel cladding at the front and protection over the valves – safety features that were not present on the tank cars involved in the Lac-Mégantic rail disaster, which killed 47 people. After Lac-Mégantic, Ottawa began phasing out the use of older-model tank cars for carrying crude oil.

Mr. Talbot said he is aware that Saturday’s derailment involved the newer-model tank cars.

“But they still ruptured, and they still caught fire,” he said. “So you know, they need to certainly look at those and see if they can do a much better job as far as the quality of cars, when hauling all this crude.”

A team of investigators from the Transportation Safety Board travelled to the area, but as of Sunday afternoon was still unable to access the scene of the accident because the fire at the site was still raging, a spokesman said.

The train that derailed was carrying a total of 94 tank cars of crude oil, John Cottreau said, adding that it was not immediately clear how many of the derailed cars were breached or how much oil was spilled. No one was injured in the accident.

There were differing reports on Sunday about how the fire had affected air quality in the region. Ontario Provincial Police advised residents in the area to stay indoors because of the smoke and to avoid drinking the water.

However, a CN spokesman said the company believes air quality is not a concern. “Ongoing air monitoring [at] the site continues to show no air-quality concerns on or off the site,” spokesman Jim Feeny wrote in an e-mail.

Chief Walter Naveau of the Mattagami First Nation said his community does not feel safe and is concerned about the effects of smoke inhalation and environmental damage.

“People in the community were feeling the affects of the toxins in the air – respiratory problems, they could feel it in their chests and their breathing,” Mr. Naveau told The Canadian Press in a phone interview.

He questioned why he should trust CN’s assurances, adding that the community is also concerned about possible contamination of the river, which leads into a spawning ground for fish, and other habitats that might be damaged by the spilled oil.

The train originated in Alberta and was bound for Lévis, Que., the Transportation Safety Board said.

Many of the fiery derailments that have occurred over the past two years have involved crude from the Bakken formation, which straddles North Dakota, Montana, Manitoba and Saskatchewan. If the crude involved in Saturday’s accident was from Alberta’s oil sands, rather than Bakken oil, that could raise new questions about whether the problem of explosive crude is in fact more widespread.

The recent accident comes just weeks after another CN train derailed about 30 kilometres northwest of Gogama, spilling more than one million litres of crude and petroleum distillate and causing a fire that lasted nearly a week.

A preliminary investigation into that accident led the Transportation Safety Board to suggest recently that the government’s new rail standards still don’t go far enough.

A spokeswoman for Transport Minister Lisa Raitt defended the government’s efforts on improving tank-car safety, noting that even tougher regulations are in the works.

“We have already banned the least crash-resistant tank cars from the system; came out last year with tougher new regulations; and have driven the acceleration of the development of a brand new standard with the U.S.,” Ashley Kelahear wrote in an e-mail.

Ms. Raitt had earlier indicated that a new tank-car standard could be announced this spring.

Mr. Talbot, who is also a member of Gogama’s emergency operations committee, praised CN officials for reacting to the accident quickly and communicating with the community. But he added that the town would be seeking answers in the future about what the company and the government will do to ensure residents’ safety.

“These trains are passing right through our community, right dead centre,” Mr. Talbot said. “And although we’ve been seeing trains go by for the last hundred years, since the Lac-Mégantic tragedy it’s brought it home a lot more, a lot closer to us.”