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Notice of Intent To Prepare an Environmental Impact Statement for the Proposed Sonoran Solar Energy Project, Maricopa County, AZ

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Bureau of Land Management, Interior.


Notice of Intent.


The Bureau of Land Management (BLM), Phoenix District Office, Lower Sonoran Field Office intends to prepare an Environmental Impact Statement (EIS) to address potential effects of a proposed solar energy project by Boulevard Associates, LLC and by this notice is announcing the beginning of the scoping process and soliciting input on the identification of issues.


The BLM will announce public scoping meetings to identify relevant issues through news media, newspapers, and BLM's Web site (​az/​st/​en.html) at least 15 days prior to each meeting. We will provide additional opportunities for public participation upon publication of the Draft EIS, including a 45-day public comment period.


Comments may be submitted by either of the following methods:

  • Mail: Sonoran Solar Energy Project,
  • ATTN: Joe Incardine, National Project Manager, BLM Phoenix District Office, Lower Sonoran Field Office, 21605 North 7th Avenue, Phoenix, Arizona 85027-2929.
  • Electronic Mail:
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For information regarding the BLM process or to have your name added to the mailing list, send requests to: ATTN: Sonoran Solar Energy Project, BLM Phoenix District Office, Lower Sonoran Field Office, 21605 North 7th Avenue, Phoenix, Arizona 85027-2929, or call Joe Incardine, 801-524-3833, or e-mail:

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The purpose of the public scoping process is to determine relevant issues that will influence the scope of the environmental analysis, including alternatives, and guide the planning process. Boulevard Associates, LLC has applied to BLM for a right of way (ROW) on public lands to construct a concentrated solar thermal (CST) power plant, a 500 kilovolt (kV) transmission line, water supply facilities, a natural gas pipeline, an access road, and other related facilities in the Little Rainbow Valley, east of State Route 85, and south of the Buckeye Hills and the town of Buckeye in Maricopa County, Arizona. The facility would be expected to operate for approximately 30 years. A ROW grant for the construction, operation, and maintenance of this Project would be required from BLM. Additional applicable permits from Federal, State and local agencies may also be required.

Boulevard Associates, LLC would construct up to 375 megawatts (MW) of solar thermal electrical generation with options for natural gas backup and/or thermal storage capabilities. The solar facility would consist of solar fields made up of single-axis-tracking parabolic trough solar collectors. Each collector contains a linear parabolic-shaped reflector (glass mirrors) that focuses the sun's direct radiation on a heat collection element located at the focal point of the parabola. The collectors would track the sun from east to west during the day to ensure the sun is continuously focused on the linear receiver. A heat transfer fluid would be heated as it passes through the receivers and then circulated through a series of heat exchangers to generate high-pressure superheated steam. The steam would power a conventional steam turbine generator which produces electricity. The plant would be made up of one or more power blocks. Each power block would be located near the center of its respective solar field and would contain multiple feedwater heaters, steam generators, steam superheaters, and feedwater pumps.

To optimize the output capacity of the project, both natural gas backup and/or thermal energy storage would be used as needed. Natural gas backup would include the addition of a partial or full load burner arrangement that would generate additional steam when solar energy is absent or insufficient by itself. Annual output from natural gas would be limited to 25 percent of annual capacity to ensure that the plant remains predominantly a solar powered facility. Thermal energy storage would provide the option of transferring some or all of the solar energy into molten salt contained in insulated tanks. Using heat exchangers and pumps designed for Start Printed Page 32642molten salt, the heat could later be extracted to provide generation when the demand for power exceeds the available generation from solar energy, essentially time shifting the solar power to respond to electric demands.

Wet cooling technology would be used for cooling the power generating equipment. Recirculating wet cooling systems use about 6 to 13 acre-feet per year per MW for a system with 3 hours of thermal storage. A mechanical draft cooling tower, cooling water circulating pumps, circulating water piping, valves, and instrumentation would also be located within the facility. Multiple evaporation ponds would be constructed to hold discharge from the cooling towers and steam cycle that can no longer be recycled back into the plant.

The Project would be connected to the electrical grid using a newly constructed, 3 to 4 mile, 500 kV generation tie-line with a point of interconnection at the existing Jojoba Substation, west of the proposed Project site and operated by the Salt River Project. If any upgrades would be required to the Jojoba Substation as a result of this Project, those upgrades would be included in the EIS analysis and ROW grant. The new transmission line and other related facilities that would be developed specifically for this Project would be included in the EIS analysis and included in the ROW grant as appropriate.

The EIS for the Project will analyze the site-specific impacts related to air quality, biological resources, cultural resources, water resources, geological resources and hazards, and hazardous materials handling. The EIS will also analyze land use, noise, paleontological resources, socioeconomics, soils, traffic and transportation, visual resources, waste management, wildlife corridors, health and human safety, and fire protection. Additionally, information on facility design engineering, efficiency, reliability, transmission system engineering and transmission line safety and nuisance will be included in the EIS. Native American Tribal consultations will be conducted in accordance with policy, and Tribal concerns will be given due consideration, including impacts on Indian trust assets. It is anticipated that the EIS process will be completed by December 2010.

To be most helpful, you should submit comments within 30 days after the last public meeting. Before including your address, phone number, e-mail address, or other personal identifying information in your comment, you should be aware that your entire comment—including your personal identifying information—may be made publicly available at any time. While you can ask us in your comment to withhold your personal identifying information from the public review, we cannot guarantee that we will be able to do so.

If the ROW were to be approved by BLM, the concentrated solar thermal power plant facility on public lands would be authorized in accordance with Title V of the Federal Land Policy and Management Act of 1976 and the Federal Regulations at 43 CFR part 2800.

(Authority: 43 CFR part 2800)

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Helen M. Hankins,

Acting State Director.

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[FR Doc. E9-15974 Filed 7-7-09; 8:45 am]