ROCK SPRINGS — A driver on Interstate 80 sees little evidence of this western Wyoming town’s coal mining past, even though shuttered mine entrances from a century-long boom are just a few hundred yards away.
Today, some residents don’t know much about the town’s legacy industry even though coal’s departure gutted the community nearly 70 years ago.
Until recently, unstable underground mines caused sinkholes that damaged city infrastructure. Now that clean-up is coming to an end with a project to shore up old coal tunnels under I-80.
As the threat of these old mines collapsing underneath parts of the city fades, Cowboy State Daily visited Wyoming’s fifth-largest town to see what’s left of these old tunnels and the work to shore them up.
The Coal Era
The Union Pacific Railroad brought the coal mining industry to Rock Springs in 1868 when the first railroad cut through Rock Springs, said Dave Johnson, a retired historical archaeologist who also serves on the Rock Springs Historic Preservation Board.
People began to survey for coal shortly after.
The coal was needed to fuel trains traveling in the region, so Rock Springs grew rapidly to meet demand.
Mines were initially operated by the Wyoming Coal and Mining Co., but in 1874, Union Pacific took control of all mining operations, launching its coal company in the process, Johnson said.
"So, they start developing their own mines in Rock Springs in a town called Carbon, which is about 100 miles east of here, and a town called Almy, which is located just north of Evanston,” Johnson said.
“The miners, of course, reacted by striking,” Johnson said. “So, Union Pacific lays off these miners and hires Chinese who had been working on building the railroad back in the 1860s.”
Then A Massacre
The new ownership came with pay cuts for the existing labor force to try and compete with coal mines across the country.
That led to Rock Springs becoming “a large center for Chinese,” he said. “In fact, by 1880, probably half the population of Rock Springs was Chinese.”
That caused a riot to break out in 1885. Local miners targeted Chinese workers and drove them out of town, killing 28 people in what’s become known as the Massacre of 1885.
“Union Pacific wasn't going to stand for this, so they rounded up the Chinese [workers] who had mostly all gone to Evanston, brought them back,” Johnson said.
Demand for labor continued, and Union Pacific expanded its search for workers internationally.
“After the Rock Springs Chinese massacre, the Union Pacific needed to find additional workers, so they start looking for people all over Europe,” Johnson said.
Rock Springs became an incredibly diverse place as a result, with miners coming from places like Slovenia, Japan and beyond.
Ten Mines, Then None
Union Pacific alone had 10 mines in Rock Springs, which collectively represented nearly a century of underground mining in the area.
The proximity of the mines to the town center was a simple practicality for the workers. It also meant digging out a lot of tunnels underneath the region.
“The towns grew up around the mines rather than the mines growing up around the town,” Johnson said.
From there, it was a natural progression to build up around where the coal was, which made it easier and more practical for workers to get to and from the mines.
“Mostly when they wanted to go to work, they had to walk,” Johnson said. “You wanted your house to be as close to where you were working as possible. So, these houses were built very close to the mines, and in a lot of cases were built directly over the mines.”
This changed in the early 1960s when demand for coal plummeted, and America’s largest railroad operators switched from coal to diesel.
“The whole city's economy had been based on mining and now mining was gone,” Johnson said. “It really had a terrible effect on the town. Many people left. Many people had no jobs or jobs that were far less well-paying than what they had in the mining industry.”
The building of a coal-fired power plant caused a boom in the 1970s, but it wasn’t enough to sustain Rock Springs indefinitely.
Today, little evidence remains of what was once one of Wyoming’s largest industrial hub for natural resource production.
The Rock Springs Coal sign can be seen downtown on display. Beyond the local museum, this sign is one of the few obvious clues that Rock Springs used to be a coal mining powerhouse in the region. (Cowboy State Daily Staff) 
David Johnson approaches the Reliance coal tipple, a preserved example of coal mining infrastructure just outside Rock Springs. Dave gives tours of the site to visitors. (Cowboy State Daily Staff) 
David Johnson stands at the site where a subsidence hole opened up overnight in 1988 just outside city hall. Rock Springs was able to repair the structure using money from the Abandoned Mine Lands division, and the building now serves as the local historical museum. (Cowboy State Daily Staff) 
A look inside the Lionkol / E-Plane Mine, showing the entrance sealed with large rock. This mine operated off and on during the 19th and 20th century, with Union Pacific eventually taking control during World War II. The mine closed permanently after the war ended and demand for coal decreased. (Courtesy Western Archaeological Services) 
A portal to the Lionkol / E-Plane Mine between Rock Springs and Reliance is pictured during survey work on the site in 2007. Sites like these are first surveyed for historical artifacts, then secured using various techniques to ensure stability of the underground structure. (Courtesy Western Archaeological Services) 
Interstate 80 is pictured in the foreground with the site of several mine entrances just beyond. Although the mine entrances have been filled in, Wyoming’s Department of Environmental Quality was working at the site as of April 2024, to ensure the stability of old mine tunnels beneath the highway. (Cowboy State Daily Staff) 
Work vehicles are pictured on Interstate 80 in Rock Springs, Wyoming. The Abandoned Mine Land Division was working to fill mine voids underneath the interstate until as recently as October 2024, when the project was completed. (Cowboy State Daily Staff) 
The Reliance coal tipple can be seen from an aerial view. Tipples like these were used to load coal for transport upon its removal from a mine. (Cowboy State Daily Staff) 
A train can be seen passing through downtown Rock Springs. When Union Pacific arrived in Rock Springs in the late 1800s, coal for demand increased, and a new industry was born. (Cowboy State Daily Staff) 
David Johnson looks at historical photographs from the first half of the 20th century while inside the Rock Springs Historical Museum. (Cowboy State Daily Staff) 
A children’s book titled “I Want To Be A Coal Miner” is displayed inside the Rock Springs Historical Museum. The culture of coal mining in Rock Springs was deeply important to both the laborers and their families. (Cowboy State Daily Staff) 
The Rock Springs Historical Museum, formerly city hall, is located on B Street downtown. The buildings structure was damaged in 1988 during a subsidence event, where an abandoned coal mine collapsed directly outside. (Cowboy State Daily Staff) 
Historical Archaeologist David Johnson explains a map that shows the extent of coal mining tunnels in Rock Springs inside the Rock Springs Historical Museum. (Cowboy State Daily Staff) 
A doorway is seen built into the rock near Veterans Park in Rock Springs, Wyoming. While the mine entrances near I-80 have been filled in, some original infrastructure can still be seen. (Cowboy State Daily Staff) 
Cement blocks are one of the few things remaining near the old coal mine entrances in Rock Springs. (Cowboy State Daily Staff)
The Aftermath
The intensive underground mining that occurred in Rock Springs didn’t go without consequences.
The mines were built using traditional methods, including wooden posts that were put in place to stop the ceilings from collapsing.
“In coal mines, you needed some type of a serious framework just to keep the tunnels from collapsing because the rock was so soft,” Johnson said.
Workers either removed the wooden posts prior to a mine being closed, or they were left to decompose with time, Johnson said. Ceilings would become unstable.
What happened next is called “subsidence,” a fancy word to say the mines started caving in.
“Depending on the rock that the roof consists of, this stuff can eventually collapse,” Johnson said.
Subsidence happens when an abandoned mine tunnel collapses and the land above sinks with it.
This was a real-life problem that many people faced in Rock Springs from the beginning of underground mining in the region up until now, Johnson said.
Historical newspapers document how houses, businesses and the local city hall were impacted at some point by shifting ground underneath their foundations.
In 1988, a sinkhole opened up just outside the main entrance of the Rock Springs City Hall building on B Street. The building didn’t collapse, but it needed a lot of work as a result, Johnson explained.
“The soil surrounding the subsidence hole is mostly sand, and the foundations of the old city hall were built into this sand,” Johnson said. “When the subsidence hole opened up, it pulled the sand away from the building, loosening the amount of soil supporting the foundation.
“As a result of this, the old city hall building began to develop cracks on the inside walls … [and] some cracks along the exterior walls.”
Johnson and other residents propositioned the Abandoned Mine Land Division for help.
Fill Them In
The Abandoned Mine Land Division was created to tackle the seemingly endless task of filling in and securing these abandoned sites. They conduct these projects all over the state in an effort to fortify Wyoming’s unseen underground spaces.
Don Newton, administrator of the Abandoned Mine Land Division, has worked on a variety of these projects across the state.
“Generally, most situations are unique. We've seen mine voids as deep as 150 feet expressing themselves at the surface, which is pretty amazing,” he said. “But a lot of the shallower mines will obviously express themselves on the surface sooner.”
Filling in old mine tunnels is tedious, requiring historical archaeologists like Johnson to first survey the site, followed by a remediation crew to secure the collapse, Newtron said. The work is important, but often not on the public’s mind.
“Most people don't know about it, but when a subsidence hole opens up in your backyard … you get to understand it in a hurry and you get to see the importance of it,” Newton said.
The crews use various techniques, but usually repairs involve filling in the mines with grout to stop future collapses.
“There's a lot of different ways in dealing with it,” Newton said. “Sometimes, a small surface subsidence can just be dug out with a backhoe and backfilled and handled that way.
“When it's more extensive and it's deeper, a lot of times we're using the grout … to fill the void as best we can to support the layers above it.”
While the work to secure all the Rock Springs tunnels is largely completed, work still continues.
As recently as this month, the Wyoming Department of Environmental Quality completed work on a $10.5 million project to fill in mines near I-80, along with other reclamation projects.
“We were concerned with the general safety and really not wanting a subsidence problem to surface on the interstate and shut the interstate down for a long period of time. So that's why we did that,” Newton said.
Miners are pictured with breathing apparatuses which were used by rescue teams and fire brigades. While these devices made rescue operations safer overall, it was still incredibly dangerous work. (Courtesy Sweetwater County Historical Museum) 
Four miners are pictured in Rock Springs, near the future corridor for Interstate 80. Date unknown. (Courtesy Sweetwater County Historical Museum) 
A group of miners from No. 7 mine pose for a photograph in Reliance, Wyoming, in 1951. (Courtesy Sweetwater County Historical Museum) 
A map shows the locations of various mine sites in Sweetwater County, including a view of mines located in Rock Springs. (Courtesy Sweetwater County Historical Museum) 
A newspaper article from September 1985 shows a sinkhole that opened up in Rock Springs near a residential area. Mine subsidence was a serious problem in Rock Springs for decades, but has largely been remedied today. (Casper Star-Tribune via newspapers.com) 
A newspaper clipping shows the Rock Springs City Hall blocked off as work is underway to survey the damage from a subsidence hole that opened up in 1988. The building was built very close to the original entrance of the Union Pacific No. 1 mine. (Casper Star-Tribune via newspapers.com) 
Workers are photographed inside a mine along with a mule and wagon. Mules were often used in the early days of coal mining to transport mine carts and haul various loads. Date unknown. (Courtesy Sweetwater County Historical Museum) 
A worker can be seen in Rock Springs’ No. 8 mine loading coal onto a conveyor belt system, date unknown. (Photo Courtesy Rock Springs Historical Museum)
Don’t Forget
Besides recent subsidence events, it’s easy to forget Rock Springs was once a coal mining powerhouse in Wyoming before the rise of the huge open-pit coal mines in the Powder River Basin.
Beyond the “Rock Springs Coal” sign that spans over downtown, visible evidence isn’t easy to find.
All the mine entrances next to I-80 have been filled in, with only a few pieces of concrete suggesting the presence of infrastructure from years past.
For people like Johnson, forgetting the past is not an option.
As a retired historical archaeologist, he spends his free time informing visitors about Rock Springs history through tours of the Rock Springs Historical Museum and other sites.
The museum hosts artifacts from the past 150 years, including photographs, newspaper archives and more. He wishes he could have seen what it was like to live in Rock Springs during the coal boom.
“It sure would be neat to see. If you had, like, a time machine that you could look back and see what these people are doing,” Johnson said. “It would make my job a whole lot easier because I wouldn't have to try and figure it out from a scatter of artifacts and a bunch of newspaper articles to actually see what's happening.”
Johnson came to Rock Springs in the 1980s from Minnesota to pursue a career in historical archaeology, planning to only stay for a short while.
“I was looking for a job, and I figured, ‘Well, this is probably as good as any.’ I arrived here around the end of August,” he said. “I figured I'd probably have about 10 weeks’ worth of work here.
“Well, this didn't work out that way. I ended up spending the next 40 years here when I expected to barely make 40 days.”
He spent that time with Western Archaeological Services, which often collaborated with DEQ to fill in abandoned mine sites.
Dave’s work allowed him a unique insight into the lives of the people who would have worked at these sites.
“You might come out to a mining site and find a mine portal is open,” Johnson said. “You find some waste material, usually coal tailings or slag, and you'll find a lot of historical artifacts left over from what these people were doing. It can be from the meals that they ate, alcoholic beverage bottles, plates, food remains.”
Although coal mining will likely never return to Rock Springs, historians like Johnson keep the legacy of the Rock Springs coal miners alive.
“It's just what I like to do. I haven't lived here all my life, so I don't really have the personal connection to the town,” he said. “I don't have family who lived here. I don't have ancestors who worked in the mines or anything.
“But it does kind of allow me to do the things that interest me and learn about a town that has become a very interesting place to me over the last 40 years that I've worked here.”
The Takeaway
The Rock Springs story is unique in some ways, but not in others.
There are hundreds, maybe thousands, of towns across the United States that lost their main industries due to lost demand for the natural resources of the region. Many Western ghost towns became deserted this way.
But Rock Springs isn’t a ghost town. Its population has grown on average since the last mine shut down operations, boasting around 22,000 residents now.
While the people may have had an identity crisis on their hands during that transition, it didn’t cause a mass exodus like in other places in the country.
Therein lies a rare success story.
Even the death of the primary industry, the main employer, the economic powerhouse that was the coal mining business, couldn’t wipe Rock Springs off the map.
And those collapsing old coal mines couldn’t swallow it up.
Contact Reilly Strand at reilly@cowboystatedaily.com
