Department of Energy 

Washington, DC 20585 

FINDING OF NO SIGNIFICANT IMPACT 

DEPARTMENT OF ENERGY LOAN GUARANTEE TO ABENGOA SOLAR INC. FOR 

THE SOLANA CONCENTRATING SOLAR POWER FACILITY NEAR GILA BEND, 

ARIZONA 

AGENCY: U.S. Department of Energy, Loan Guarantee Program Office 

ACTION: Finding of No Significant Impact 

SUMMARY: The U.S. Department of Energy (DOE) has conducted an environmental 

assessment (EA) that analyzed the potential environmental impacts associated with a 280 

Megawatt (MW) concentrating solar power (CSP) plant (Solana Generating Plant) and 

associated 230 kilovolt transmission line (Solana Gen-Tie) proposed by Abengoa Solar Inc. 

(Abengoa) near Gila Bend, Arizona (Solana Project). DOE, through its Loan Guarantee Program 

Office (LGPO), proposes to provide a Federal loan guarantee pursuant to Title XVII of the 

Energy Policy Act of 2005 (EPAct 05), as amended by Section 406 of the American Recovery 

and Reinvestment Act of 2009, to Abengoa to support the construction and startup of the 

proposed facility.' The purpose of DOE'S proposed action is to expedite the deployment of a 

new energy technology into commercial use in the U.S. and to reduce emissions of greenhouse 

gases and other air pollutants. 

The Solana Project would use CSP technology to capture heat generated by sunlight and turn that 

heat into electricity. CSP works by using parabolic trough systems to concentrate energy from 

the sun through long, curved mirrors. Approximately 2,700 trough collectors covering roughly 

1,757 acres would comprise the "solar field." The parabolic trough systems would be tilted 

toward the sun and focus sunlight on a pipe running down the center of the trough. Heat from 

sunlight would warm an organic synthetic oil, known as heat transfer fluid, which would flow 

through the pipe to the power island. The heat transfer fluid would serve as the working fluid of 

the collector field, and would provide a means for transferring the collected solar energy to the 

heat exchangers. The collected solar energy would be used to convert water to steam for use in a 

conventional steam turbine generator to produce electricity. The Solana Project would employ 

molten salt storage tanks to retain and store up to 6 hours of heat, which could be dispatched as 

needed, and would allow Solana to produce electricity on cloudy days and after sunset. 

The Solana Project would interconnect to the regional transmission grid via the Solana Gen-Tie, 

which would originate at the Solana Generating Plant and terminate at the existing Arizona 

Public Service Company Panda Substation, approximately 18.2 miles east of the Solana Project. 

The Solana Gen-Tie would consist of transmission structures, single-circuit conductors (three 

wires), and two overhead ground wires, one of which would contain a fiber-optic cable to serve 

as a communications system for the Solana Project. The transmission structures would be steel 

' The amount requested for the loan guarantee is not being disclosed at this time because it is business sensitive. 

Moreover, should DOE approve a loan guarantee, the amount may differ from the original request. 

@ Printed with soy ink on recycled, paper 
monopoles approximately 100 to 140 feet tall, depending on the span length required, with a 

maximum height of 190 feet above the ground surface. 

All discussion and analysis related to the potential impacts of construction and operation of the 

proposed Solana Project are contained in the Final EA (DOEIEA-1683), whch is incorporated 

here by reference. DOE examined potential impacts on the following resources and found none 

to be significant: floodplains; wetlands; water resources and water quality; threatened or 

endangered species and critical habitats; prime or unique farmlands; geology and soils; visual, 

recreational, and aesthetic resources; property of historic, archaeological, or architectural 

significance; Native American concerns; environmental justice; public health and safety; air 

quality; global climate change; waste management; transportation; socioeconomic conditions; 

noise; and terrorism-related impacts. 

In accordance with applicable regulations and policies, DOE sent a notification letter regarding 

the Department's determination to prepare an EA to American Indian Tribes, the Arizona 

Department of Environmental Quality and the City of Gila Bend on July 8, 2009. The letter 

described the proposed action and stated that a draft EA would be sent to the state for review. 

On April 6,2010, DOE sent the Draft EA to American Indian Tribes, the Arizona Department of 

Environmental Quality, and the City of Gila Bend inviting their comments on the draft. The 

Draft EA was also posted on the Loan Guarantee Program Office website. DOE received a 

comment letter from the Arizona Department of Environmental Quality (AZ DEQ) on April 27, 

2010, requesting clarification on the use of the sewage pumps mentioned in Table 3-7 (Sound 

Level Specifications for Standard Packaged Equipment) of the Draft EA. Information was added 

to the EA indicating that these are transfer pumps which channel wastewater fkom cooling tower 

blowdown to evaporation ponds and would not involve sewage. The letter also provided 

additional information regarding the process for various AZ DEQ permits that were listed in the 

EA at Table 2-1. 

DETERMINATION: On the basis of the Final EA, DOE has determined that providing a 

Federal loan guarantee to Abengoa for construction and startup of a 280MW CSP facility and its 

associated transmission line near Gila Bend, AZ, will not have a significant affect on the human 

environment. The preparation of an environmental impact statement is therefore not required, 

and DOE is issuing this Finding of No Significant Impact. 

Copies of the Final EA are available at the DOE Loan Guarantee Program Office website at 

http://www.lmo~.ener~;y.g! " FA-1 .htd or from 

Joseph Marhamati 

NEPA Document Manager 

U. S. Department of Energy 

1000 Independence Ave, S W 

Suite 4B-196 CF1.3 

Washington, DC 20585 

- - 
Additional information on the DOE NEPA process is available from: 

Carol M. Borgstrom, Director 

Office of NEPA Policy and Compliance (GC-54) 

U.S. Department of Energy 

1000 Independence Avenue, S W 

Washington, DC 20585 

202-586-4600 or 1-800-472-2756 

& 

Issued in Washington, DC on the b day of in the year 

athan Silver 

xecutive Director, Loan Program