The rail line runs some 1,260 miles from the Powder River Basin to west coast ports. Along the way, it cuts through 32 communities and towns in Montana alone, crossing 167 public roads and highways en route.
Billings, Montana's largest city with a population of 104,000, has access to resources unavailable to most other communities on the rail line and is perhaps best equipped to tackle the issue.
The city, hard against a bend in the Yellowstone River, with 800-foot-tall sandstone bluffs hemming it to the north, was built by the railroad in the 1880s and has tied its fate to train traffic ever since.
Cattle dominated trade in the early years, but today oil is the economy: Three of the state's four oil refineries, representing 94 percent of Montana's production, are in or near Billings. Last spring the city made national headlines when the Yellowstone River, running at flood stage due to heavy snow melt, scoured away a pipe carrying crude oil to the Exxon refinery in Billings, dumping 42,000 gallons of crude in the river according to the company.
Trains have always run right through the heart of downtown; three blocks west of one of the main downtown crossings, the twin rail lines split into three, then five, then nine lines and more as the rail yard mushrooms, cleaving the town.
The city has always been blue collar. The boom in expensive, second-home markets that buoyed Bozeman, two hours to the west, never materialized in Billings. The downtown core, left gutted and boarded up in the exodus to the city's outskirts in the 1970s, has only recently started to revive.
That renaissance has been a fragile one, and the prospect of tripling train traffic downtown was enough to draw more than 100 people to a two-day meeting on issue earlier this spring.
Gulick and others fear the costs could be considerable. Sending 148 million tons of coal a year by rail through Billings - a questionable assumption, Burlington Northern Santa Fe railway officials are quick to note - would mean 42 more coals trains a day through downtown Billings: 21 full trains a day heading west, 21 empty trains returning east.
Gulick has spent a fair bit of time sitting in traffic downtown. By his watch, a coal train keeps crossing gates down an average of eight minutes. The extra coal trains, when combined with current freight traffic, would block downtown's thoroughfares for up to eight hours a day, he estimates.
Dr. Robert Merchant, a Billings pulmonologist, fears the health cost could be considerable, too. Coal trains bring diesel exhaust, coal dust and noise. All three have health consequences, he said.
Diesel exhaust has been linked to cancer and it can exacerbate asthma; noise has been linked to increased blood pressure. Research around the world has concluded that whenever soot increases, more people die from heart attacks and respiratory problems.
Then there's the coal dust: By BNSF's own estimates, coal trains lose 3 percent to 4 percent of their coal en route to their destination. Powder River Basin coal is particularly friable and easily pulverized. experts say.
"A marked increase in coal trains will markedly impact the health of my patients," Merchant said. "I need to keep them out of the hospital."
Burlington Northern says the city's fears are premature at best. Billings would only see 42 extra trains if all the coal terminals were built, all were operating at capacity, and the railroad sent every ton of coal through Billings, said Zack Anderson, a BNSF spokesman. "That's just not going to happen."
"There's a potential for increased traffic," he acknowledged, but the railroad has other options to get that coal to port. "It's like the telephone network or the Internet," Anderson added. "You want to route things where there's less congestion."