Citizens of Chaffee County, homeowners, land and business owners, farmers and ranchers, hunters, and even tourists will be impacted in some way or another.  Our county prides itself on having one of the most beautiful landscapes in Colorado. The Arkansas Valley is a pristine area where people have chosen to live and visit due to the quietness and beauty of the area, as well as all the outdoor activities.  Our county should not be marred by a large geothermal electrical power plant.  The proposed location of the geothermal power plant site could gravely impact nearby homeowner water wells, i.e., drying up, contamination.  Mt. Princeton Hot Springs could be at risk as a result of geothermal wells tapping into hot water aquifers that could divert natural underground hot water away from Chalk Creek.  Wildlife and the migration of elk, mule deer, moose and other animals will be impacted.

Mt. Princeton Geothermal, LLC, in partnership with Western Geothermal, with financial backing from Colorado Energy Office (grant funding) and Reykjavik Geothermal, a foreign entity.  (1), (2)

According to Mt. Princeton Geothermal, LLC (MPG), the physical location is directly next to Dry Creek, in the Maxwell Park State Trust Land area, East side of County Road 321 (Rodeo Road).  Between CR 323 (Mount Princeton Road) and CR 327. The three well sites have been referenced to be both on the west side of CR 321 near the entrance to the Lost Creek development (CR 323) and also the east side of CR 321. MPG has stated that the test wells will become production wells. (1)

Mt. Princeton Geothermal, LLC has secured a lease from the Colorado State Land Board for exploration of Maxwell Park, including drilling, of 3692.31 acres.  The area of the geothermal electrical plant main facilities will encompass approximately 8.5 acres of land adjacent to Dry Creek. The remainder of the 3692 acres, can be used for further geothermal exploration, development and drilling of additional production and injection wells.  The short-term impact areas is stated to be 25 acres for this particular proposal. (1)

According to Mt. Princeton Geothermal, LLC, they are planning to initially build a 10 megawatt production plant with future plans to increase the size of the facility and production rate to 40 megawatts. (1)

According to Mt. Princeton Geothermal, LLC, test, production and injection wells may be as deep as 4,000 – 8,000 feet into the ground.  It all depends on what the test wells reveal. Test wells will be a minimum of 2,500 feet deep. (1)

YES.  Geothermal water cooling towers do create a condensation steam plume that is visible, especially during winter months. (5)

Presumably, NO.  All production of electricity is sent to a main grid, which in turn, is sold to other cities and/or surrounding States for the highest dollar.

YES.  Air and water pollution are two leading environmental issues associated with geothermal energy technologies. Additional concerns are the safe disposal of hazardous waste, siting and land subsidence. Most geothermal power plants require a large amount of water for cooling and other purposes. This need could raise conflicts with other water users or uses such as fish spawning and rearing in areas where water is in short supply. Steam vented at the surface may contain hydrogen sulfide, ammonia, methane and carbon dioxide. Dissolved solids are discharged from geothermal systems.  All of these releases, if concentrated, can create localized fish and wildlife kills. Geothermal resource development is often highly centralized, so reducing their environmental impacts to an acceptable level is achievable. (4)

YES.  All geothermal plants produce noise 24/7.  Electrical generators, cooling towers and other facility components necessary to operate the plant produce continuous noise day and night. Security lighting is part of the infrastructure of the site.  Such lighting at night could violate Colorado House Bill, HB22-1382, Dark Sky Designation.  (4), (5)

While considered a clean energy source, binary closed-loop geothermal power plants do have some potential pollution risks, primarily related to the release of trace amounts of gases like carbon dioxide and hydrogen sulfide during extraction, although these emissions are generally minimal compared to fossil fuel power plants and are significantly reduced in a closed-loop system due to the lack of direct contact between the geothermal fluid and the atmosphere; however, proper management and mitigation strategies are still necessary to minimize any potential environmental impact. The impact is described in relation to different development phases of the geothermal power plant facilities. Those phases are:

• Access roads and pipe laying and power lines, plant and associated land use.

• Well repair, well stimulation, well drilling and testing phase.

• Surface disturbances, such as those caused during the plant construction and equipment installation possibly affecting flora, fauna, surface water. 

• Power plant commissioning and operation.

• Decommissioning of facilities. 

Physical effects, like the effect of fluid withdrawal on natural manifestations, land subsidence, induced seismicity, visual effects (buildings, cooling towers, surface pipelines, power transmission lines etc.)  Noise, such as equipment noise during drilling, construction and operation. Thermal pollution, due to hot liquid and steam release on the surface. Chemical pollution, due to disposal of liquid and solid waste, gaseous emissions to the atmosphere etc. (4) (11)

Depending on the geothermal source, the extracted water may contain dissolved solids, such as sulfur, chlorides, silica compounds, vanadium, arsenic, mercury, nickel and other toxic heavy metals that need to be carefully managed to avoid environmental contamination.  (4)

YES.  There is a number of wildlife species that live in the area and around the Colorado State Trust Land and their designated wildlife areas, (hence the name “Maxwell Park Wildlife Area”.  Lost Creek Ranch, State Trust Land and surrounding lands are a migratory path for the large Mount Princeton elk herd that moves between the forested area to the valley floor then to the Arkansas River for feeding.  There are also a number of other species in the area, including moose, mule deer, bobcat, mountain lion, bear, red fox, snowshoe hare, hawks, and Bald Eagles.  It has been reported that a Lynx was sighted as well.  Deep exploratory drilling, the years of construction, further drilling for production and injection wells, and continuous noise will negatively impact all wildlife in the area, perhaps permanently.   (6)

According to the Colorado State University, Survey of Critical Biological Resources Chaffee County, Colorado, “Dry Creek” at Maxwell Park is considered a wetland and riparian area.  Dry Creek watershed is a tributary that feeds the Arkansas River, of which the U.S. Army Corps of Engineers have jurisdictional oversight for the protection and permitting of projects affecting this watershed.  (7), (8)

Not definitively known. There is a potential risk of wells running dry or becoming contaminated. Water seeks the point of least resistance.  Therefore, geothermal wells that tap into underground water aquifers could redirect underground water sources away from existing homeowner wells.  (6)

Not definitively known. There is a potential risk of water being diverted away from the spring source. (6)

According to Mt. Princeton Geothermal, LLC, there would be an initial labor increase for the construction of the site.  After construction and during normal plant operation, there would be a small operational staff. There would be an increase in tax revenues but these are estimates.  The actual numbers are unknown. (1) (6)

YES, there is increased seismic risk, specifically small earthquakes. Small earthquakes are associated with binary closed loop geothermal power plants, notably the drilling deep into the earth and injecting fluids which can sometimes trigger instability along existing fault lines. This can lead to induced seismicity.  However, the risk is typically considered low compared to other geothermal technologies like enhanced geothermal systems (EGS) that involve more aggressive rock fracturing.  Studies have demonstrated that geothermal reservoirs may exhibit ground deformation and micro-seismicity.  Geothermal reservoirs have the potential to undergo deformation as a result of many factors, such as thermoelastic and poroelastic stresses, as well as seismic and aseismic fault slip along preexisting faults. These faults experience both pressure and poroelastic stress changes due to fluid injection and production in wells for the reservoir properties, which can lead to small earthquakes. (10)

According to Mt. Princeton Geothermal, LLC, the proposed location is the “best” location in Colorado for naturally occurring geothermal reservoirs.  However, according to a Colorado Geological Survey report, July 2024, the best location for geothermal resources are near the areas of Grand Junction, Eastern Plateau of Colorado, and Southern- Central Colorado.  Chaffee County is not listed in this report. (1), (3)

YES, binary closed-loop geothermal plants can be considered inefficient due to relatively high parasitic power requirements to operate plant components such as cooling water pumps, tower fans, feed pumps and well pumps. This consumes a large part of the generated power.  Geothermal power plants have lower efficiency relative to other thermal power plants, such as coal, natural gas, oil, and nuclear power stations.  (9)

Initially yes. The process of drilling and building the infrastructure of the geothermal plant would temporally bring jobs to the area.  (Consider, though, that there is a housing shortage locally.) However, once the initial construction is complete, the manpower needed to operate and maintain the plant is minimal.  For example, the Blue Mountain Geothermal Power Plant employs a total of 14 people (49.5 MW).  According to Mt. Princeton Geothermal, LLC, there would be an initial labor increase for the construction of the site of approximately 167 people.  After construction and during normal plant operation the total number of jobs is 15.  (1), (6)

YES.  During a site visit at the Blue Mountain Geothermal Power Plant, it was acknowledged by the facility manager that there was a problem with injecting water back into the ground at the rate necessary to replenish the underground reservoir.  Additionally, oil must be inserted into the well in order to lubricate well pumps, which can contaminate the surrounding soil. Further, a seismic activity study was conducted revealing data that micro-seismicity has been detected at this site. At the Lightning Dock Geothermal plant in New Mexico, rancher’s water wells allegedly were drastically affected.  (6) (10)

Not definitively known, but it’s reasonably possible given the long-term risk to homeowner’s water wells of going dry as a result of geothermal wells.  Also, the ability to sell and a longer time to sell are risks if a geothermal utility plant is developed close to homes and property.

(1)  Mt. Princeton Geothermal, LLC Nov. 30th, 2023 community meeting presentation

(2) https://www.chaffeecountytimes.com/news/mt-princeton-geothermal-announces-partnership/article_ae2f29fa-33e3-11ef-9286-8b607b49fd3a.html

(3)   https://ecmc.state.co.us/library.html#/gtccsungs    (Geothermal in Colorado: Resources, Use Strategies, and Impact Considerations – Full Report, July 2024: https://ecmc.state.co.us/documents/library/GTCCSUNGS/Geothermal_in_Colorado_Accessible.pdf)

(4) U.S. Fish and Wildlife Service   https://www.fws.gov/node/265252

(5) Colorado State HB22-1382 Dark Skies Determination and Promotion   https://leg.colorado.gov/bills/hb22-1382

(6)  Save our Arkansas Valley website, Blue Mountain Geothermal site visit presentation, https://static1.squarespace.com/static/66ff1a0e0e7fdb2a1281d55a/t/677b1e8751e3716b12f66535/1736122184036/BlueMountainGeothermalPowerPlantWinnemucca-Web2.pdf.

(7)   https://cnhp.colostate.edu/wp-content/uploads/download/documents/2009/CHAFEE_FINAL_REPORT05_14_2009.pdf

(8) https://www.spa.usace.army.mil/missions/regulatory-program-and-permits/jurisdiction/

(9)   https://www.sciencedirect.com/science/article/abs/pii/S0960148120302299#:~:text=Parasitic%20loads%20can%20constitute%20a%20significant%20loss,generator%20output%20internally%20due%20to%20parasitic%20loads

(10)  https://www.sciencedirect.com/science/article/pii/S0012821X24003169

(11)  http://www.geoelec.eu/wp-content/uploads/2014/03/D-4.2-GEOELEC-report-on-environment.pdf

(12)  https://www.themountainmail.com/news/article_f241403e-1ec0-11ef-b960-abde46c7af94.html