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The Dixie Valley Geothermal Area is located near Fallon, Nevada. It lies along a range front fault that runs between the base of the Stillwater Range and the northwestern edge of Dixie Valley. The fault line and thermally active area are roughly 30 km long. It stretches from the Dixie Valley Geothermal power plant on the north side of the geothermal zone to the Dixie Hot Springs Geothermal Area on the south side. The Dixie Meadows Geothermal Area also lies within this thermally active fault zone. There are a few other hot springs nearby: Seven Devils, Sou, and Hyder hot springs. There are also three blind systems within the valley: Dixie Comestock Mine, Pirouette Mountain, and Eleven Mile Canyon.


The Dixie Valley Geothermal Area is the hottest and largest known geothermal system in the Basin and Range Province. The geothermal production area is divided into two groups of production wells: Section 33 and Section 7; injection wells are located between the two production zones in section 5. Each zone is about 1-3 km long and they are not hydrologically linked at depth. A third zone that lies to the south of the production area, called Dixie Valley Power Partners (DVPP), has not been developed yet and is not hydrologically linked to the current production zones, but exhibits similar thermal characteristics.


The Dixie Valley Geothermal Area is a fault-controlled geothermal system and is the hottest known deep-circulation system in the Basin and Range province. The quantity and diversity of geophysical, geological, geochemical, hydrologic, and other studies conducted at Dixie Valley are also much greater than those performed at any other geothermal area in Nevada. Consequently, the amount of available information at Dixie Valley provides a unique template for understanding and developing other Basin and Range geothermal systems. In recent years, the site has been used as a case example for Basin and Range systems. Several adaptations of conventional geothermal exploration techniques have been tested and calibrated at Dixie Valley for the identification of resources suitable for development as Enhanced Geothermal Systems (EGS).


In addition to the geothermal resource, Dixie Valley hosts several gold deposits near the Senator Fumaroles, and so has received some attention from the gold mining industry.  Dixie Valley has also been in the spotlight due to the occurrence of several large earthquakes in the area, the most notable being in 1954 when a 7.2 magnitude earthquake struck at Fairview peak, followed by a 6.7 magnitude earthquake four minutes later associated with rupturing of the Dixie Valley Fault. These quakes produced large surface ruptures and drew the attention of many researchers.


There is one geothermal power plant in Dixie Valley, located at the northern end of the valley about 100 km northeast of Fallon, Nevada. It is currently the largest geothermal power generation facility in Nevada, which was initiatally rated for production of 500 MW. The smaller plant power plant was constructed and brought online in 1988 and was originally owned by the Oxbow Group. In 2000 it was purchased by Caithness Energy, and then in 2010 Terra-Gen Power, LLC acquired the facility.


The power plant produces only 67 MW (although rated much higher), the current plant has the highest energy output of any other geothermal power facility that is not associated with recent magmatic activity, albeit driven by hydrogeological systems heated by relatively shall magmatism. The energy produced at the Dixie Valley Power Plant was being sold to Southern California Edison. Geothermal activity in the Dixie Valley area was first reported in 1968 by surveyors.  By the late 1970s and early 1980s Dixie Valley became a competitive location for geothermal exploration with 11 different companies engaged in exploration activities. For one of the first industrial investigations, see: http://www.mdcampbell.com/MDCGeotherm83Fla2.pdf 


In 1985, the Oxbow Geothermal Corporation acquired three separate geothermal leaseholds in the Dixie Valley area. The acquisitions came from Sun Company and Trans-Pacific-Geothermal who each held Power Purchase Agreements (PPAs) with Southern California Edison. They each planned to build power plants of 10-20 MW, but the high transmission costs that were associated with the projects prevented development. By combining the two smaller ventures into one 67 MW plant, the 220-mile, 230-kV transmission line that was needed to connect with Southern California Edison became economically feasible. The line became the largest privately owned electric transmission facility in the United States. Oxbow hired Ebasco Services as the turnkey contractor and Ben Holt Company as the project engineer for the 3.5-year plant construction. The single-unit, double-flash power plant also became the largest geothermal plant of its kind in the country when completed in July 1988. The generating station produced electricity from a geothermal resource of around 249°C from a 2400-3050 m depth interval in the permeable fracture zone of the Dixie Valley fault.

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