September 27, 2024 |
Photo – Graphic of proposed storage facility at Seminoe Reservoir – Courtesy NS Energy
The Federal Energy Regulatory Commission sought public comments this week on the proposed Seminoe Pumped Storage Project. The gathering had a more of a “career night” feel than that of a public meeting, though.
On Wednesday evening, in the Jeffery Memorial Center in Rawlins, representatives from the Federal Energy Regulatory Commission and rPlus Hydro of Utah met formally to educate the public and collect comments about a proposed pumped storage project at the Seminoe Reservoir.
rPlus Hydro is seeking to construct a pumped storage power plant at, and under, the Seminoe Reservoir.
During a June 26th meeting in Sinclair, rPlus Hydro Chief of Staff Theresa Foxley explained that the pumped storage facility will act like a giant battery. When electricity is abundant, water will be pumped from the Seminoe Reservoir into an upper lake that will be constructed specifically for the project. When energy demands outpace production, Foxley said the stored water will be allowed to flow downhill through a turbine to generate electricity.
Building the pumped storage facility will be a massive undertaking. Construction will require creating a nearly 11,000-acre-feet, man-made lake on a hilltop in the adjacent Bennett Mountain Wilderness Study Area to store water for the hydro power project. Below ground, a large industrial complex must be built to house a hidden complex of electrical generation equipment.
Estimates put the cost of the entire project at around $3 billion. When completed, rPlus Hydro officials claim the project will generate over 900 megawatts of electricity over the course of 10 hours as water flows downhill from the upper lake, through the turbine, and back into the Seminoe Reservoir.
The project will impact boating and recreational opportunities on the lake.
rPlus Hydro wants to construct a 20-foot wide, 65 to 180-foot-high concrete dam to contain 10,800-acre-foot of water in the man-made lake above Seminoe. When power is needed, a 75-foot-wide pipe on the southwestern edge of Seminoe will channel water over three electrical turbines.
The design calls for the dam to produce maximum output of 972 megawatts over the course of 10 hours as the water from the upper reservoir flows back down into the Seminoe Reservoir.
In addition to the underground tunnels and turbine facility, the Bennet Mountain Road must be extensively overhauled to allow heavy construction traffic to travel to the power station.
rPlus Hydro is proposing to draw a total of 13,400 acre-feet of water from the Seminoe Reservoir to initially fill the new upper lake, with 10,800 acre-feet of the water available to be used to generate electricity. The upper lake is expected to lose 272 acre-feet of water every year due to evaporation and other natural causes. Filling the upper lake is expected to take approximately 14 hours.
Such a large project is subject to oversight by various state and federal agencies. Wednesday was the final Federal Energy Regulatory Commission scoping meeting for the project. According to the federal agency, the purpose of scoping is to identify issues, concerns, and opportunities for enhancement or mitigation associated with a proposed action.
Wednesday night’s meeting was to allow the public to learn more about the project and submit comments.
The first Seminoe Pumped Storage Project scoping meeting was held in Casper on Tuesday afternoon. A representative from FERC told Bigfoot99 that very few people submitted comments at that time.
The second, and last, scoping meeting occurred on Wednesday evening at the Jeffery Center in Rawlins. Representatives from rPlus Hydro set up a number of booths in the auditorium with information about the proposed facility. Members of the Federal Energy Regulatory Commission were on hand with a court reporter to collect public comments. All comments made during both meetings, and through the FERC website, will become part of the public record.
Upon learning about the project, many residents expressed concern about the potential impact the pumped storage facility will have on the Seminoe Reservoir and nearby Miracle Mile. When operational, the facility is expected to change the water level of the reservoir by six to 18 inches, depending on the level of the lake when the facility is put into operation.
Additionally, even slight changes to the water composition, such as increased or lowered oxygen levels, could have negative impacts on trout fishing in the area.
The Federal Energy Regulatory Commission’s scoping document states that rPlus Hydro is required to perform a series of environmental protection and enhancement measures as part of the project. Included in the proposal is the development of a storm water pollution prevention plan designed to prevent contamination of surface waters from storm water runoff during construction. Also, rPlus Hydro is required to install and maintain fish exclusion bar racks on the 30-foot-wide input and output pipe in the Seminoe Reservoir to reduce the number of fish that are sucked into the pipes during operation.
The upper lake will be entirely fenced off to prevent fishing and other recreational activities.
The next step in the lengthy development process is a National Environmental Policy Act review of the project.
Potential impacts to water turbidity, temperature, and dissolved oxygen from Seminoe Reservoir all the way to the North Platte River must be studied. Additionally, investigations must be done on the effects construction and the occasional lowering and raising of the water level of Seminoe Reservoir will have on water quality.
The Federal Energy Regulatory Commission will accept written comments about the Seminoe Pumped Storage Project until November. The following month, FERC will either issue a second scoping document to address problems identified in the comment process or move the project onto the next step, an environmental analysis.
If rPlus Hydro clears the permitting hurdles and receives approval, construction would begin construction in June of 2026.
