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Identification Protocol for New/Expanded SEZs

Protocol Overview

Section A.2.6 of the Western Solar Plan stated that the BLM intends to identify new and/or expanded solar energy zones (SEZs) in the context of existing solar market conditions, existing and planned transmission systems, and new (or existing) State or Federal policies affecting the level and location of utility-scale solar energy development. The BLM planned to assess the need for new or expanded SEZs at least once every 5 years in each of the six states covered by the 2012 Solar PEIS.

The planned process to identify new or expanded SEZs would be open and transparent, with opportunities for substantial involvement of multiple stakeholders. The BLM would identify new or expanded SEZs at the State or field office level as an individual land use planning effort or as part of an ongoing land use plan revision. The planning of new or expanded SEZs would tier from the 2012 Solar PEIS and utilize information carried forward from the PEIS to assist in the analyses. BLM's goal would be to complete the work to identify new SEZs and amend applicable land use plans within 12 to 18 months of initiating such efforts.

Steps in SEZ Assessment Process

The BLM will use the following criteria when considering whether to identify new or expanded SEZs. In most situations, SEZs should be:

  • Relatively large areas that provide highly suitable locations for utility-scale solar energy development,
  • Locations where solar energy development is economically and technically feasible,
  • Locations where there is good potential for connecting new electricity-generating plants to the transmission distribution system, and
  • Locations where there is generally low resource conflict.

The following four steps highlight a sequential process for identifying potential new or expanded SEZs:

1. Assess Demand for New or Expanded SEZs

Demand Assessment

The BLM will assess the demand for new or expanded SEZs as part of the regular land use planning process or as a separate effort to determine the role BLM-managed lands should play in broader energy and climate goals. While Federal, State, tribal, and local stakeholder involvement will be essential to the process, BLM State Directors will ultimately be responsible for making the determination whether additional SEZ acreage is needed. Acknowledging that significant changes can occur in the interim between assessments, the BLM will also provide for an assessment triggered by a petition process.

Petitions for New or Expanded SEZs

Petitions for new or expanded SEZs must be submitted in writing to the appropriate BLM State Director with documentation supporting the request. Petitions must have a rational basis and should be linked to factors such as policy, environmental, and/or market changes (e.g., increase in state or national renewable standards, development of new transmission capacity, economic development, population growth, or availability of financial incentives).

Developers, environmental stakeholders, local and State governments, industry associations, and others may collectively or individually petition the BLM to consider specific areas for new or expanded SEZs. Petitioners may also request changes in already identified SEZs, such as eliminating or revising boundaries due to changes in the status of species or critical habitat under the Endangered Species Act (ESA). In addition to the petition process, the public may also raise the need for new or modified SEZs through the scoping process for individual land use plans.

Considering Demand for New or Expanded SEZs

When considering the demand for new or expanded SEZs, the BLM will take into consideration relevant national policy goals and trends in the solar market. The BLM will rely on outside expert consultation, such as DOE and State energy offices, regarding electricity demand, markets, and renewable energy policies. Utility-approved plans, State public utility forecasts, and regional planning outcomes, such as those originating with the California Independent System Operator (CISO) and the Western Electricity Coordinating Council (WECC), can all provide useful input into BLM's determination of demand for additional SEZ acreage.

The BLM will also consider the availability of land in existing SEZs when it evaluates the need for new or expanded SEZs. The BLM's assessment of demand may require the development of new State-based Reasonably Foreseeable Development Scenarios that incorporate new Federal or State policies affecting projections.

2. Establish Technical and Economic Suitability Criteria

In addition to considering the demand for solar energy across a State or region, BLM's process for identifying new or expanded SEZs will take into account technological advances in solar energy generation systems and/or transmission infrastructure, energy load centers and associated flow, existing and planned transmission lines, and any known constraints to development. These additional factors will influence the decision regarding which general region will be chosen for new or expanded SEZs.

A number of factors determine the technical and economic suitability of an area for utility-scale solar energy development, including the quality of the solar resource, terrain, and proximity to existing load and infrastructure. These factors may vary by State and/or region and will continue to evolve over time. As part of its SEZ identification process, the BLM will work with outside experts, industry, transmission planning organizations, State and local agencies, and other stakeholders to establish and apply appropriate technical and economic suitability criteria.

Size Threshold

An SEZ should generally encompass an area large enough to accommodate multiple utility-scale solar energy projects, provide flexibility for siting, and provide opportunities for shared infrastructure. SEZs on public lands should also be large enough to generate ample quantities of solar-generated power to justify the effort and expense required to determine whether the area is well suited for solar energy development. Smaller areas of BLM-administered lands located adjacent to private, State, or other Federal lands that are suitable for solar energy development may, however, be appropriate for consideration as SEZs if they can be used in conjunction with adjacent areas.

Solar Insolation

Solar insolation levels in areas identified for new or expanded SEZs will typically be high, thus allowing for optimum power production. Higher insolation values provide significant benefits for solar generation facilities. Under BLM's Solar Energy Program, areas with direct normal solar insolation levels less that 6.5 kWh/m2/day would not be available for individual applications without an approved land use plan amendment (i.e., they would be excluded). However, in view of expected technological advances, shifting market conditions, and evolving State and Federal policies, the BLM may consider the identification of new SEZs in areas with insolation levels lower than 6.5 kWh/m2/day. Providing this type of flexibility for SEZs is consistent with the policy objective identified in 2012 Western Solar Plan of working with industry and other stakeholders to identify additional SEZs in which there is a combination of industry interest and reduced conflicts.

Different types of insolation are most relevant to the different large-scale solar generating technologies. For concentrating solar technologies, direct normal insolation is most pertinent, while for photovoltaic (PV) systems, global tilt insolation is the appropriate measure of the solar resource. As part of the process to identify new or expanded SEZs, the BLM may consider both direct normal insolation and global tilt insolation depending on the technologies being contemplated for a given SEZ.

Slope Threshold

Most solar generating technologies must be sited on relatively flat ground to ensure that the solar collectors can utilize the solar resource effectively. Depending on the technology, the required slope can range from less than 2% to more than 5%, although lower slopes are generally better for siting solar energy generation. Under BLM's Solar Energy Program, areas with slopes greater than 5% would not be available for individual applications (i.e., they would be excluded). However, as part of the process to identify new or expanded SEZs, flexibility in applying the slope criterion may be appropriate, particularly for PV or dish engine technologies that are more adaptable to land with steeper slopes. In considering new or expanded SEZs, areas with higher slopes should be otherwise well suited for development. It is unlikely that lands with slopes of greater than 10% would be technically viable for utility-scale solar production.

Load Areas To Be Served

When considering the appropriate locations for new or expanded SEZs, the BLM will consider the load areas likely to be served by new solar generation. The BLM will rely on outside expert consultation regarding electricity demands, markets, and renewable energy policies (e.g., DOE, State energy offices).

The BLM will also consider relevant Federal and State policy goals and trends, such as possible retirement of generating facilities and/or State Renewable Portfolio Standard (RPS) policy (or policies). For example, the RPS in a given State may have been met, and new solar energy development would be expected to serve demand in another State. The location for new SEZs would therefore have to consider existing or proposed transmission lines and capacity available to move new generation to load out of state. Consideration would also have to be made for the importing State's RPS policy (or policies).

Infrastructure Access

As part of the identification of new or expanded SEZs, the BLM will consider proximity to existing infrastructure, such as transmission lines, utility corridors, roads, and a suitable workforce. Where SEZs can be located close to existing infrastructure, environmental disturbance may be minimized through the use of the existing facilities (in some cases, however, transmission lines may be sited in environmentally sensitive areas that are not suitable for locating SEZs). The use of existing infrastructure may also reduce construction and mitigation costs, making locations close to existing and useable infrastructure attractive to developers.

Transmission Systems

New or expanded SEZs should be located in areas sufficiently close to load centers or in areas where transmission can be reasonably expected to be available in time to serve the quantity of generation planned. The BLM will consult with State and regional transmission planning and coordination authorities, State energy offices, and transmission system operators to evaluate available capacity on existing and proposed lines and to discuss other potential transmission-related barriers.

In considering potential locations for new or expanded SEZs, the BLM should catalog all existing and proposed transmission lines serving an area in relation to the power generation potential from a proposed SEZ. Consideration should also be given to foreseeable changes in load, such as retirement of generating facilities. Where new transmission lines are needed, they should be planned to utilize existing rights-of way (ROWs) or designated utility corridors to the extent practicable.

In considering potential locations for new or expanded SEZs, the BLM should catalog all existing and proposed transmission lines serving an area in relation to the power generation potential from a proposed SEZ. Consideration should also be given to foreseeable changes in load, such as retirement of generating facilities. Where new transmission lines are needed, they should be planned to utilize existing rights-of way (ROWs) or designated utility corridors to the extent practicable.


The ability to utilize existing paved roads for access to SEZs can also reduce impacts associated with development; therefore, SEZs should be located adjacent to major paved roads where possible. For potential SEZs where existing paved roads are located some distance away, existing dirt roads should be upgraded for site access to the greatest extent possible in order to minimize land disturbance. Finally, the proximity of the SEZ to a potential workforce should be considered to promote sustained workforce success in the SEZ region.

3. Apply Environmental, Cultural, and Other Screening Criteria

Program Exclusion Criteria

To identify potential SEZs with low resource conflicts, BLM State and field offices will screen areas for the presence of resources or other values that the BLM has determined in the 2012 Western Solar Plan to be unsuitable for utility-scale solar energy development rights-of-way (ROWs) (see Exclusion Criteria).

Relevant Land Use Plan Decisions

BLM State and field offices undertaking efforts to identify new or expanded SEZs will consider all relevant decisions in existing land use plans (e.g., ROW avoidance and exclusion areas, timing restrictions). Although it may be necessary to amend existing land use plan decisions as part of identifying new or expanded SEZS, such decisions serve as a valuable screen for potential conflicts.

Coordination and Outreach

In order to understand potential resource conflicts and opportunities and/or barriers for solar energy development, BLM State and field offices will coordinate with appropriate Federal, State, and local agencies, and tribes (including, but not limited to, the agencies described below). The BLM also may decide to reach out to the local public and other stakeholders such as local sportsman groups. Such coordination and outreach would likely result in the development of locally relevant screening criteria to be applied in the identification of potential new or expanded SEZs. During coordination and outreach, the BLM will:

  • Consult with State and local (county and/or municipal) governments to identify opportunities for new or expanded SEZs and to consider consistency with officially adopted local plans and policies (e.g., comprehensive land use plans, open space plans, conservation plans) and permit requirements (e.g., special use permits)
  • Consult with State resource management agencies to discuss potential resource conflicts.
  • Engage in government-to-government consultation with tribes to identify traditional cultural properties and sacred sites with areas related to new or expanded SEZs.
  • Consult with appropriate land management agencies for consideration of areas in close proximity to special designations such as the National Parks, National Refuges, and National Forests.
  • Consult with the U.S. Department of Defense (DoD) for consideration of impacts on military installations and operations.

Such consultations may result in agreements not to locate SEZs near specific units, based on an agency's assessment of potential adverse impacts on those units.

Landscape-Scale Information

The BLM will use landscape-scale information (e.g., BLM's rapid ecological assessment, California's Desert Renewable Energy Conservation Plan (DRECP), The Nature Conservancy's eco-regional assessments, and State-level crucial habitat assessment tools) to identify and to exclude from SEZs areas of high ecological value or importance. For example, in areas with pre-existing landscape-scale conservation plans, such as the DRECP in California, future SEZs will not be considered in areas needed to achieve biological goals and objectives established in the plan.

Other types of areas to screen for based on landscape-scale information may include areas with significant populations of sensitive, rare, and special status species or unique plant communities, important biological connectivity areas, designated wildlife habitat management areas, lands with wilderness characteristics, and areas with high concentrations of ethnobotanical resources of importance for Native American use.

Potential landscape-scale information would be evaluated in coordination with relevant Federal, State, and local resource management agencies and tribes.

Degraded, Disturbed, or Previously Disturbed Sites

In identifying potentially suitable lands for SEZs, BLM State and field offices will seek opportunities to locate new or expanded SEZS in degraded, disturbed, or previously disturbed areas. Examples include, but are not limited to, the following:

  • Lands that have been mechanically altered, such as fallowed agricultural lands;
  • Lands that have been “type-converted” from native vegetation through plowing, bulldozing, or other mechanical impact, often in support of agriculture or other land cover change activities (e.g., mining, clearance for development, or heavy off-road vehicle use);
  • Brownfields and other contaminated or previously contaminated sites, such as those identified by the U.S. Environmental Protection Agency's (EPA's) RE-Powering America's Land Initiative or State, local, and/or tribal authorities;
  • Idle or underutilized industrial sites;
  • Lands adjacent to urbanized areas and/or load centers;
  • Areas repeatedly burned and invaded by fire-promoting non-native grasses where the probability of restoration is determined to be limited; and
  • Areas where co-location of solar energy development with other energy development may be feasible (e.g., wind or oil and gas development).

Amendment of existing land use plan decisions may be necessary to allow for new or expanded SEZs on degraded, disturbed, or previously disturbed areas. Sources of information on degraded, disturbed, or previously disturbed areas should include:

  1. Landscape-scale information and landscape-scale ecological assessments (e.g., landscape conservation cooperatives, rapid ecological assessments, and State-level crucial habitat assessment tools) which identify converted or highly degraded lands on BLM-administered and adjacent Federal and non-Federal lands;
  2. Coordination with the EPA and relevant State agencies that catalog degraded, disturbed, or previously disturbed sites; and
  3. Outreach to local communicates and the public regarding possible degraded, disturbed, or previously disturbed sites.

Opportunities to Combine Other Federal and Non-Federal Lands

As part of the SEZ identification process, the BLM will take into account opportunities to partner with adjacent Federal and non-Federal landowners (e.g., private, State, tribal, or DoD-withdrawn lands). For example, small SEZs may be appropriate on BLM-administered lands when they are located adjacent to degraded, disturbed, or previously disturbed private lands. This combination of BLM-administered and non-Federal lands could allow for a combined use area, allowing for the expansion of renewable energy development onto well-suited adjacent lands.

Information from BLM Monitoring Efforts

As part of the SEZ identification process, the BLM will review and consider information gathered through its proposed long-term monitoring and adaptive management program. Information gathered through monitoring studies will help the BLM regularly evaluate resource conditions, detect change, and augment its knowledge of potential resource conflicts associated with solar energy development. This information will be used to inform the identification of new priority areas for utility-scale solar energy development.

In addition, the BLM has expanded its knowledge of areas that are suitable/not suitable for development through the evaluation of individual solar energy ROW applications. Areas eliminated from ROW applications because of resource conflicts (e.g., rare vegetation or desert washes) may provide additional screening criteria for new or expanded SEZs.

4. Analyze Proposed SEZs

Notice of Intent

The BLM will publish a Notice of Intent (NOI) in the Federal Register stating its intent to prepare a Land Use Plan amendment (or amendments) to identify a new or expanded SEZ or multiple SEZs and to prepare the associated NEPA documentation. The NOI will also begin the formal scoping process (40 CFR 1501.7). Through the scoping process, the BLM will solicit additional input on potential SEZs, and the public will be invited to nominate proposed SEZs that meet the objectives of the planning effort. Based on scoping, the BLM will identify a potential SEZ, multiple SEZs, or SEZ configurations to be analyzed through the planning and NEPA process. The BLM will document the results of its scoping in a publicly available scoping report (43 CFR 1610.2(d)).

NEPA Review

When the BLM is preparing NEPA analyses for new potential SEZs, its goal will be to produce documents with comprehensive analyses of resources at a level of detail sufficient to allow for tiering of future solar energy projects within the SEZ if it is designated. Analysis of SEZs will also include consultations pursuant to the Endangered Species Act (ESA) and the National Historic Preservation Act (NHPA). The potential impacts associated with the development of transmission interconnection and other infrastructure to support the establishment of an SEZ will be considered as part of the NEPA review for the SEZ. The BLM will also seek opportunities to designate any necessary utility corridors that would support the establishment of any new or expanded SEZs in a combined planning effort. The BLM will make the draft land use plan amendment and draft NEPA document available for a 90-day public comment period (43 CFR 1610.2(e)). Following the preparation of a proposed land use plan amendment and a Record of Decision (ROD) on the NEPA document, and after reviewing and resolving any protests, the BLM would issue a decision about whether to amend affected land use plans to establish a new SEZ(s).

Impact Categories

Through the planning and NEPA process, the BLM will refine SEZ boundaries and may establish SEZ-specific management prescriptions based on resource-specific considerations. Chapter 5 of the 2012 Solar PEIS includes a comprehensive description of the impacts of constructing and operating solar energy generation facilities and related infrastructure and possible mitigation measures in the categories below. This information will be used as a guide to inform the analysis of SEZs. The categories are as follows:

  • Lands and realty,
  • Specially designated areas and lands with wilderness characteristics,
  • Livestock grazing,
  • Wild horses and burros,
  • Wildland fire,
  • Recreation,
  • Military and civilian aviation,
  • Geologic setting and soil resources,
  • Minerals,
  • Water resources,
  • Ecological resources,
  • Vegetation and plant communities,
  • Wildlife,
  • Aquatic biota,
  • Special status species,
  • Air quality and climate,
  • Visual resources,
  • Acoustic environment,
  • Paleontological resources,
  • Cultural resources and Native American concerns,
  • Socioeconomics,
  • Environmental justice, and
  • Cumulative impact considerations.