The CarbonSAFE Project in Campbell County hopes to provide a future for coal
The second of two test wells are nearing completion near the Dry Fork Station power plant north of Gillette that could inject carbon dioxide (CO2) thousands of feet into the ground to keep it from entering the atmosphere.
The CarbonSAFE (Carbon Storage Assurance Facility Enterprise) projects were announced in 2016 to focus on storing CO2 from industrial sources like coal-fired power plants. The National Energy Technology Laboratory's (NETL) objective, which is overseeing the CarbonSAFE initiative project-wide, is to store 50 million metric tons of CO2 from these industrial sources. If the current schedule is kept to, injection at sites project-wide is slated to begin by 2026.
“The beauty of this one [Dry Fork Station] is we’re testing the capture, we’re testing the storage with CarbonSAFE,” said Dry Fork Station Manager Tom Stalcup. “We got the coal plant, got the Integrated Test Center to develop capture technology, and now with CarbonSAFE, the storage component of it.”
As the coal industry has declined in past years, these kinds of technologies have gained traction, not only from the energy industry, but also from those in academia. The University of Wyoming’s School of Energy Resources (SER) has a presence at Dry Fork and is actively involved with the CarbonSAFE initiative.
“This is an R&D (research and development) project and we’re doing a lot of testing,” said Dr. Holly Krutka, Executive Director of the School of Energy Resources. “We’re drilling these wells and getting data about what’s in the subsurface to help us understand exactly how much CO2 can be injected.”
The SER has been working on the project for years and the project is now in its third phase, which is slated to last for three more years. This includes completing the permitting processes and moving toward commercialization of a carbon capture and sequestration facility, among others.
“This is actually the second reservoir that we’re studying in Wyoming,” Krutka said. “The team also studied the Rock Springs Uplift previously, so Wyoming is going to be one of the only states with two fully characterized reservoirs—we’re really trying to understand what the CO2 storage capacity is across the state.”
Even with lots of research, what is known about the state’s CO2 storage capacity remains to be fully understood.
“Just understanding two reservoirs still is just scratching the surface, there’s so much that could be done to understand how much CO2 can be stored here,” she said.
But it is clear how coal has contributed to utility companies and electric power cooperatives. Basin Electric owns Dry Fork Station and supplies power to approximately three million member-owners in nine states through local electric cooperatives, the majority of which are in rural areas. They’re a sponsor of the CarbonSAFE project at Dry Fork, as is the State of Wyoming. They also own the Laramie River Power Station near Wheatland.
Basin Electric has scaled back significantly on the power they provide that is generated from coal in the last 20 years. However, approximately 40 percent of their current power generation still comes from coal-fired plants.
“This is really exciting, quite frankly,” said Chris Baumgartner, Senior Vice President for Member Services and Administration for Basin Electric. “The possibility of what we have here [is that] we have a wonderful facility sitting next to a very ample supply of fuel, sub-bituminous good coal—this plant could run for a long, long time.”
The implication of what technologies, such as carbon capture and sequestration, have to offer optimism to Baumgartner and Basin Electric.
“If we can find a way to capture the carbon, and then utilize it and put it beneath the ground, this is a very, very good thing, for not just Basin Electric and our members, but quite frankly for the energy security of the country,” he said. “If this can done here at the Dry Fork Station and the technology is there and we can do it economically, there’s potential to do this other places throughout the country, and then you have that reliability component and you can incorporate wind and solar and batteries and natural gas and you combine those with the reliability that coal provides you—it [has] tremendous potential.”
Though carbon capture and sequestration projects have taken place elsewhere in the country, according to Baumgartner CarbonSAFE at Dry Fork Station is unique.
“This would be almost the first of its kind at a large scale,” he said. “Basin Electric does have quite a bit of experience in that itself, we have another facility in North Dakota [a coal gasification facility]—we extract the CO2 out of there, and we’ve being doing that for 20 years and we send that to Canada, so we have a little bit of experience, and that’s one of the largest carbon capture projects in North America.”
The Wyoming Department of Environmental Quality (DEQ) is involved in the permitting process for the CarbonSAFE project.
“Our primary focus is the well itself,” said Lily Barkau, Groundwater Section Manager for the DEQ. “Our primary role here at DEQ is to permit those wells—we provide the permitting for underground injection control wells, Class 1, deep disposal wells, Class 5, which are your more shallow disposal wells, and now Class 6.”
The current site is still a Class 1 well according to Barkau. In the future, it will be permitted under a different classification specifically designated for carbon sequestration.
“At this point, it's considered a Class 1 [primarily for oil and gas waste products] injection well,” she said. “Class 6 is specific to carbon sequestration, so they’ll be similar to Class 1—the requirement is that they inject below the lowest most underground source of drinking water.”
Though there will be groundwater at the depths to which CO2 may be deposited, Barkau claimed it won’t interfere with water that can be used for drinking water.
“There’s various formations that will have some sort of groundwater present, but that groundwater isn’t considered a source of drinking water,” she said. “What makes a source of drinking water is the total dissolved solids concentration, so if it’s less than 10,000 milligrams per liter of total dissolved solids and can be produced at a certain rate, typically at around one gallon per minute, that would constitute an underground source of drinking water.”
When completed, the wells will be approximately 10,000 feet deep where CO2 would be deposited.
“These are going to be very deep [wells that inject CO2], thousands of feet deep, even below the USDW [underground source of drinking water] that exists,” Barkau said.
"The rock layers above it [of the deposited CO2] are subject that the geology of those will not come through those [rock layers]," Baumgartner said.
Stalcup likens the layers of rock to a kind of sealed barrier.
"It would be like a clay seal keeping this CO2 from getting up above it," he stated.
DEQ regulations require evaluations of the caprock to determine if there is a potential for disposed of materials to leak upwards. There is also the potential that deposited CO2 could have chemical impacts where it’s deposited.
“It could crystallize and form additional minerals, there could be chemical reactions depending on the fluids that are present there, but it just depends on the information that’s provided, what outcome shows up we would look at as part of permitting, said Barkau.“The potential for that to happen should be extremely minimal provided that the site characterization has been thoroughly done, We would look at the modeling that’s presented to ensure that those risks are extremely minimal to none.”
Additional wells would have to go through the same process as the two existing ones, must be permitted individually, and would proceed directly to the Class 6 permitting process. Wells that are near existing ones may also face limits as to how much can be deposited in them if it’s determined that their contents will interfere with a neighboring one, Barkau said.
The Dry Fork Station is also home of the Wyoming Integrated Test Center, a facility that opened in May 2018 which allows researchers to test carbon capture and sequestration technologies.