The Federal Energy Regulatory Commission has issued an original license to the 1,300-MW Eagle Mountain Pumped-Storage project, proposed for an inactive iron mine in Riverside County, Calif.
FERC staff issued a final environmental impact statement in 2012 recommending issuance of a license to Eagle Crest Energy Co. for the project (No. 13123). California issued state water quality certification under Clean Water Act Section 401 last year, paving the way for FERC licensing.
Utilizing a head of 1,400 feet between two reservoirs created from abandoned mining pits, Eagle Mountain would be a closed system, not linked to a river. Because the former mining site already has sustained significant environmental disturbance, further development of the site for pumped storage would have little additional environmental impact, Eagle Crest said.
The pumped-storage project is to provide energy storage needed to efficiently utilize intermittent renewable energy sources such as wind and solar energy.
FERC’s licensing order, issued June 19, licenses the project as proposed by Eagle Crest with some staff modifications and additional measures, primarily to mitigate environmental effects. The primary environmental issues associated with the project are effects of its construction and operation on groundwater, water quality, and terrestrial species, including several sensitive bat species, the desert bighorn sheep, and the threatened desert tortoise.
The project includes construction of two saddle dams and liners for the proposed reservoirs. Groundwater is to be pumped from a series of proposed wells in the Chuckwalla Basin to fill the reservoirs and replace water lost to evaporation. A reverse osmosis system is to be installed to remove salts and metals from the reservoirs to help maintain water quality of the reservoirs and counteract degradation associated with evaporation.
The Eagle Mountain mine had been the largest employer in the area until its closure in 1983. Construction of the pumped-storage project would employ about 100 during peak construction and provide tax revenues to county and local governments. Project operation would provide about 30 jobs and substantial property tax payments.
The project, with staff modifications, would produce power in the first year that is $141.1 million, or $32.76 per megawatt-hour, less than the cost of alternative power.