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Wabuska Hot Springs (Tad's Enterprises) (updated 2008)

The Wabuska geothermal area is located at the margin of Mason Valley, where both the valley margin and the thermal springs coincide with a northeast-trending zone of faults (Stewart, 1999) referred to as the Wabuska lineament (Stewart, 1988). Hot springs, about 1.6 km north of Wabuska, range in temperature from 59 to 72°C and occur over a large area in Secs. 14,15,16,23, Tl5N, R25E. Gas bubbles issue from the pools with a faint odor of H₂S (Stearns and others, 1937). According to Russell (1885, p. 48, 49), the springs occur along an east-west line that coincides with the course of a post-Lahontan fault, which is plainly shown by an irregular scarp, in some places 6 m high. The springs occur in circular mounds; the water is collected in small basins and evaporated, reportedly forming a saline deposit, a section of which is described below (Russell, 1885):

2-5 cm :white, hard crust of sodium sulfate with sodium chloride, some calcium carbonate.
5-17 cm: soft, mealy or clayey deposit of sodium sulfate, calcium carbonate, calcium sulfate, etc.
2.-2.5 m: clear, transparent crystals of sodium sulfate with some impurities; resting on saline clay.

The American Sodium Co., using evaporating ponds, refined and shipped sodium sulfate from here in the 1930s. Davis and Ashizawa (1960) have suggested that a chemical company might be able to use hot water from wells to refine sodium sulfate. Samples of mixed sodium chloride and sodium sulfate from surface incrustations reportedly show minor amounts of potash but no lithium, rubidium, cesium, nitrate, phosphate, or borate salts (Moore, 1969, p. 40).

In 1959 Magma Power Co. drilled three steam wells at the Wabuska area. Two of the wells were shallow (less than 183 m) and the third was drilled to 678 m, with a maximum reported temperature of 108°C. Several water wells in this area have temperatures above 27°C. Also, a well about 6.4 km to the southeast reportedly has 21°C water. Samples of water from the Magma Power Co. wells yield estimated reservoir temperatures of 145 and 152°C based on silica and Na-K-Ca geothermometers (Mariner and others, 1974).

In 1972 Agri-Technology Corp. built greenhouses near the site of the steam wells. The company planned to grow vegetables hydroponically, especially tomatoes, using hot water from the wells to heat the greenhouses. Only a few vegetables were grown before the company went out of business. A geothermal-powered ethanol plant, using grain as a feedstock, was constructed by Tads Enterprises at Wabuska in the early 1980s, and produced alcohol for gasohol for several years. The area has also been the site of efforts to grow spirulina algae as a human dietary supplement and several pilot studies to raise Malaysian prawns, catfish, and tropical aquarium fish (Hess and Garside, 1994). None of these non-electric uses were active in 2002.

Long and Brigham (1975a) and Peterson (1975) have reported on audiomagnetotelluric and gravity data in the Wabuska area.

Wabuska has the distinction of being the home of not only the first geothermal power plant constructed in Nevada, but being the one that produces electricity from the coolest reservoir, and being the smallest plant. During the 1980's, two 0.6 MW binary units were installed at Wabuska that produce from a 107°C reservoir at 107 m and that discharge spent fluids to a wetland rather than reinjecting the fluids. Wabuska 1 was put into operation in 1984, and Wabuska 2 was operational in 1987. A retrofit in 1997 changed the working fluid from fluorocarbon to iso-pentane. The plant was purchased by the Egbert family from the Townsend family in 2000. Production is apparently from Quaternary gravels and sands; geothermal fluid may circulate along faults related to the Wabuska lineament as well as an unconformity above Mesozoic metasedimentary rocks possibly present at depth (NBMG files).

As of late 2006, "Wabuska Nevada is home to the world's first geothermally powered and heated biodiesel plant, run by Infinifuel Biodiesel" (Infinifuel Corporation, 2006). For full article, see www.infinifuel.com/wabuska.htm . Infinifuel Wabuska is currently producing under 1 million gallons per year of biodiesel but has the capacity to produce 4-5 million gallons per year as sources for the raw materials are developed.

The Wabuska power plant came on-line in 1984 and has an equipment generating capacity of 2.2 MW. In 2006 electrical production at the plant was 8,234 MWh gross with 5,120 MWh net generation (Nevada Division of Minerals, 2007).

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