When the Wyoming Department of Environmental Quality (DEQ) first started cleaning up sites with underground petroleum leaks in 1989, the state agency had a list of 37 contaminated properties in Teton County.
That number has since dwindled to four thanks to the state’s remediation efforts, though cleanups are still underway in Jackson.
One spot that remains is a brown field at the north end of town on a prominent route to Grand Teton National Park. Many of the park’s more than 3 million annual visitors stream past the empty lots dotted with shipping containers and a remnant of weathered buck-and-rail fence corralling little more than weeds before reaching sought-after pristine views.
But for Jackson — a town whose mission statement makes environmental stewardship a top priority — transforming this eyesore has been complicated.
While past plans to develop the beleaguered site have stalled, Utah-based Mogul Capital is seeking approval from the town of Jackson to build what would be the town’s largest private commercial development on top of a plume of chemicals left behind from leaky underground fuel tanks. Like many gas stations across America, the Teton Texaco that once stood on the site’s north end contaminated the soil and groundwater, leaving behind a legacy of carcinogenic pollution that has taken decades to clean up.
Mogul’s plans have shocked residents because of the sheer scale of the project spanning 11 lots, but there’s also concern about what’s lurking underground.
If not addressed properly, watchdogs warn that the leftover benzene, now a fifth of its original size, according to the Wyoming Department of Environmental Quality, could leach into structures built above it and further contaminate groundwater or nearby Flat Creek in an area that has a high water table.
The DEQ has consulted with AECOM, a national engineering firm, which wrote a “dig and haul” proposal to move the remaining contaminated soil off-site to Sublette County.
But in an unexpected turn, DEQ rejected its consultant’s plan. Mogul learned about the decision in the Teton Texaco annual report released last month. There are a variety of site-specific factors that caused DEQ to change course, one being that the site is a bit of a sticky wicket. Digging up contaminated soils and hauling them away has been tried before.
“Although 186 tons of soil were removed from the site [in 1990], the contamination was not resolved,” DEQ spokesperson Kimberly Mazza said in an email.
Removing more dirt could risk “soil liquefaction.” DEQ Storage Tank Program manager Jason Fernandez said that was a top concern because of the property’s high groundwater and tight soils. DEQ is taking into account the state highway — the one most Jackson visitors take to and from Grand Teton and Yellowstone national parks.
“We were afraid if they dug a hole adjacent to those important infrastructure, roadways, sewer lines, et cetera, that those soils would collapse and possibly impact that infrastructure,” Fernandez said. “All these risks can be mitigated, but our consultant did not address them, and we did not want to buy off on a program that had that much risk.”
Yet another approach, injecting microbes, also has shown limited results.
“Injections were attempted several times, but also were not effective due to the soil characteristics,” Mazza said.
Remediation tactics used for other Jackson sites, like pumping and treating the pollution, can be slow and costly. DEQ said even with these alternatives, the initial risks don’t go away and there’s no guarantee that afterwards the plume would be gone because the site’s clay and silt tend to keep a tight grip on the benzene.
As to why DEQ has been able to remediate other sites to the agency’s standards much faster, Fernandez said the ground beneath the old Texaco is complicated by its soil makeup.
But that’s not the only challenge stalling clean-up efforts at the site.
“We have multiple developers coming in, coming up with different plans, and we’re afraid that if we put a system underground, that it will just be torn up when they do construction,” Fernandez said.
That already happened when previous Teton Texaco buildings were demolished, some of DEQ’s onsite monitoring equipment was ripped up in the process, Fernandez added.
“We just don’t want to duplicate the work and pay for it twice,” Fernandez said.
Since 1990, Wyoming has leaned into a federal and state-funded remediation initiative after legislators created the “storage tank corrective action account.” The Storage Tank Program has been widely considered a national success story for cleaning up leaky underground storage tanks, with Wyoming even outperforming other states.
Wyoming’s program takes private companies responsible for the fuel leaks off the hook for cleaning up or paying for the remediation — the aim being to relieve the burden on small businesses. The same goes for future developers, which, unless they choose to take on the liability and costs associated with taking remediation a step further, are not required by the state to do so.
“If [Mogul] doesn’t want to do that, there’s always the case that they could cap [the plume] and build over it,” Fernandez said.
The state would still continue remediation, he said, and work underneath the new buildings.
Mogul’s latest plan is to build a “bathtub” to isolate the contaminated groundwater and soil as they keep the rest of the plume onsite and build on top of it.
“If the DEQ says, ‘continue what we just told you,’ which is to build over and not disturb it, that’s our plan. If they come back with a different recommendation in working with the environmental consultants, we will follow that plan,” Mogul CEO Brad Wagstaff said at a recent council meeting.
Mogul is still in the conceptual planning phase for its mix of hotel rooms, condos, restaurant and spa, though the Jackson Town Council has tacked on several conditions that will steer how the development stage is approached. With the question of the plume still looming, one of the conditions requires the developer to pay for the town’s third-party environmental review to better understand the risks around the plume.
At Monday’s council meeting, Wagstaff appeared frustrated that the town wasn’t on track to pass his sketch plan despite DEQ granting the go-ahead to keep the plume in the ground. He added that DEQ’s latest report shows the plume continues to shrink.
“We have a buildable project that is compliant, meets all requirements to move forward with this project [and] we will continue to work with DEQ,” Wagstaff told the council.
The council postponed a vote after two meetings deliberating on the conceptual plan and is now holding a special meeting Wednesday for the vote.
After rejecting the last iteration, DEQ expects to have a new remediation plan by early 2026. It’s possible that Mogul’s more detailed development plan could come out before then, which made some on the town council interested in fast-tracking DEQ’s new remediation plan.
The 2026 data point is key for the town to make an informed decision on Mogul’s development plan, at least according to Planning Director Paul Anthony.
“That’s the risk that the developer right now is taking, having a plume on their property. That is their burden to convince us that they have met their burden and provide us the information [elected officials] need ultimately to approve the project,” Anthony said at Monday’s council meeting.
When asked if the state would speed up its new remediation plan, the DEQ said it is still working on additional subsurface investigation work and stuck to its timeline.
“The data will be finalized at the beginning of next year,” the agency told KHOL. “Once the data is finalized, a new remedial action plan will be completed.”
The remediation methods DEQ implements are bounded by both cost and priority. The four Jackson sites the DEQ is still remediating pale in comparison to the 250 sites it is currently working on across the state, though the DEQ added that it is committed to resolving each site until it reaches its remediation standard.
