A propane leak from a rail car in east Saint John has been safely resolved, after more than six hours.
Emergency crews reopened Highway 1 in both directions at about 6:30 p.m. AT.
The highway was closed between Garden Street and Ashburn Lake Road around noon, shortly after the leak was reported.
The area within about 90 metres of the rail yard near the One Mile interchange overpass was also evacuated.
The leaking car was coupled with one carrying crude oil, said fire Chief Kevin Clifford.
With the train derailment and explosion in Lac-Mégantic, Que., in July still fresh in everyone's minds, authorities were taking no chances.
"There is a release of a flammable product and we're not comfortable opening the highway up when that release is still kind of off and on," Clifford said, shortly before rush hour.
"We will try to get it open as soon as we can."
Clifford initially thought the leak at the former CN rail yard, now managed by NB Southern Railway, was contained, but quickly realized the propane was still being released intermittently.
He believes the problem was a faulty relief valve on the pressurized tank. It had frosted up from the leaking gas, making it difficult to close.
Crews transferred the propane from the nearly full rail car to another tanker, said Clifford.
Traffic continued to be rerouted until the leak was resolved. No city streets were closed, but many were bumper to bumper with commuters, including Rothesay Avenue and City Road.
Hazardous materials team on site
NB Southern Railway crews noticed "misting" and the smell of gas around a single propane rail car that had been shunted from the Irving Oil refinery to the east side rail yard, said company spokeswoman Mary Keith.
"The transit of these cars was uneventful and without incident," she said in a statement.
As a precaution, crews called the fire department, RST Industries, an Irving-owed tanker truck company as part of the Liquid Petroleum Gas Emergency Response Team, as well as refinery response personnel, Keith said.
Transport Canada and the New Brunswick Department of Environment were also advised, she said.
"To be clear, no injury to any person and no derailment has occurred," Keith stressed.
Dozens of tank cars marked DOT-111A were in the rail yard, reports CBC's Connell Smith.
Such cars, which are used to transport a wide variety of dangerous goods, such as crude oil, have a maximum capacity of about 130,000 litres.
Following the Lac-Mégantic disaster, which killed 47 people, 50 organizations have called for a ban on shipping oil in older DOT-111A tanker cars.
At least eight people from Irving Oil's hazardous materials team were on scene, along with NB Southern Railway officials.
A Transport Canada truck was also on site.
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