NEPA Decarbonization Technologies Analysis: Deliverable 1
Decarbonization Technologies Project Landscape
Executive Summary
This report aims to create the following set of deliverables:
Data on number of projects tagged with decarbonization technologies within the dataset: number of projects broken down by technology (e.g., offshore and onshore wind, solar, geothermal, nuclear), lead agency, and location
For a full description of how “decarbonization technologies” are defined and classified in this analysis — including inclusion/exclusion criteria and the overall project universe — see the Project Overview document (last updated 2026-03-18).
Technology Distribution
Key Findings: Technology
Utilities, Electricity Transmission, and Nuclear Technology dominate the decarbonization technology NEPA landscape. Utility and Electricity Transmission projects comprise the largest share, reflecting the infrastructure build out required to connect renewable generation to load centers. The prominence of nuclear and solar projects are interesting. When looking at how decarbonization technology tags breakdown by review process, most are granted “Categorical Exclusion (CE)” status, with Hydropower, nuclear, and wind producing projects to be notable exceptions.
The first deliverable examines how projects tagged with decarbonization technologies breakdown by technology.
A second interesting analysis is to view how the technologies break down by review process.
Lead Department and Lead Agency
Key Finding: Agency
Department of Energy (DOE) dominates decarbonization technology NEPA reviews (81% of projects), followed by Interior (17%). DOE processes the vast majority through Categorical Exclusions (CE) (96%).
This section examines project counts by lead department and lead agency. Table 1 reports counts by department and review process, Figure 3 visualizes project counts by department, and Figure 4 shows the process type breakdown for the two agencies with complete data coverage: DOE and BLM.
Warning
Data coverage note: NEPATEC assembles EIS data from EPA’s governmentwide EIS database (comprehensive for all agencies since 2012) but EA and CE data only from DOE and BLM. Agencies outside these two therefore appear with near-zero EA and CE counts — this reflects a data gap, not actual agency behavior. Process-type mix comparisons are only reliable for DOE and BLM.
The decarbonization technology NEPA portfolio is highly concentrated: DOE alone accounts for roughly four out of every five projects. This reflects both DOE’s broad mission — spanning national labs, weapons facilities, grid modernization, and loan programs — and the fact that NEPATEC’s EA and CE collection is most complete for DOE. The Department of the Interior’s share is driven primarily by BLM’s permitting role for large-scale renewables on federal land.
| Department | Categorical Exclusion | Environmental Assessment | Environmental Impact Statement | Total |
|---|---|---|---|---|
| Department of Energy* | 16,151 | 338 | 241 | 16,730 |
| Department of the Interior* | 3,213 | 212 | 244 | 3,669 |
| Other Independent Agencies | 0 | 1 | 93 | 94 |
| Department of Agriculture | 40 | 11 | 41 | 92 |
| Major Independent Agencies | 0 | 3 | 30 | 33 |
| Department of Defense | 2 | 1 | 15 | 18 |
| Department of Transportation | 2 | 1 | 7 | 10 |
| General Services Administration | 3 | 0 | 7 | 10 |
| Department of Homeland Security | 4 | 1 | 4 | 9 |
| Department of Health and Human Services | 0 | 1 | 3 | 4 |
| Department of Housing and Urban Development | 0 | 1 | 1 | 2 |
| Department of Commerce | 1 | 0 | 0 | 1 |
| Department of State | 0 | 0 | 1 | 1 |
| Department of Veterans Affairs | 0 | 0 | 1 | 1 |
| Department of the Treasury | 0 | 0 | 1 | 1 |
| Total | 19,416 | 570 | 689 | 20,675 |
* Only DOE and DOI have complete CE, EA, and EIS data in NEPATEC 2.0; all other departments are represented only via EPA’s governmentwide EIS database.
The raw project counts in Figure 3 confirm DOE’s dominance in absolute terms. All other departments collectively account for less than 2% of the portfolio, a result that partly reflects genuine mission differences and partly the data coverage gap — those agencies appear almost exclusively through EPA’s EIS database and therefore contribute only EIS records.
Where the coverage data is reliable — DOE and BLM — the process type mix tells a slightly different story for each. DOE processes the overwhelming majority of its decarbonization actions as Categorical Exclusions, consistent with its large volume of routine lab operations, equipment upgrades, and smaller energy projects. BLM, by contrast, processes about 10% of its actions via Environmental Assessments (EA) and Environmental Impact Statements (EIS), reflecting the greater site-specificity and environmental sensitivity of renewable energy siting decisions on federal public lands.
Geographic Distribution
Key Finding: Geography
Projects tagged with decarbonization technologies concentrate in the Western states and South Carolina. South Carolina has the most projects (largely driven by nuclear projects at the Savannah River Site), followed by Washington, California, and Idaho. The county-level map reveals clustering around major federal facilities and high-resource renewable areas (desert Southwest for solar, nuclear facilities, and national labs). There does not seem to be a clear finding for the distribution of the NEPA review process by type.
The final deliverable examines geographic location of projects. Table 2 reports project counts by NEPA process type, Figure 5 visualizes that with a state map, and Figure 8 does so by county. Click here for a complete table of project count by county, which is prohibitively large.
State-Level Distribution
| State | Categorical Exclusion | Environmental Impact Statement | Environmental Assessment | Total |
|---|---|---|---|---|
| South Carolina | 2,000 | 16 | 8 | 2,024 |
| Washington | 1,748 | 81 | 43 | 1,872 |
| California | 1,474 | 173 | 87 | 1,734 |
| Oregon | 1,205 | 67 | 31 | 1,303 |
| Colorado | 1,149 | 37 | 34 | 1,220 |
| Idaho | 838 | 74 | 50 | 962 |
| Arizona | 791 | 65 | 88 | 944 |
| Nevada | 791 | 97 | 21 | 909 |
| Wyoming | 638 | 43 | 7 | 688 |
| Texas | 576 | 12 | 14 | 602 |
| New Mexico | 490 | 36 | 13 | 539 |
| New York | 511 | 20 | 8 | 539 |
| Utah | 470 | 38 | 7 | 515 |
| Pennsylvania | 462 | 8 | 6 | 476 |
| Illinois | 439 | 9 | 12 | 460 |
| Montana | 312 | 40 | 6 | 358 |
| Each project may be in multiple states, meaning totals may sum to greater than project total of 25,000. |
South Carolina clearly sticks out with the number of projects in the state. Click here to explore a more detailed table of projects there.
Figure 6 shows the top 20 states ranked by total decarbonization technology project count. South Carolina leads with over 4,000 projects, followed by Washington, California, and Idaho. This geographic concentration reflects both the location of major federal facilities (like the Savannah River Site in South Carolina) and regions with high renewable energy potential.
Figure 7 examines how the NEPA process type varies across the top 15 states. While most states show a high proportion of Categorical Exclusions (CE), there is notable variation in the share of Environmental Assessments (EA) and Environmental Impact Statements (EIS). States like Washington and California show more diverse distributions across process types, suggesting a mix of project scales and complexities.
County-Level Distribution
County-level geographic data is available for approximately 48% of projects tagged with decarbonization technologies overall. However, coverage varies significantly by NEPA review process, as shown in Table 3 below.
| Process Type | Total Projects | With County Data | Missing County | Recoverable1 |
|---|---|---|---|---|
| CE (Categorical Exclusion) | 20,863 | 9,631 (46%) | 11,232 (54%) | Not recoverable |
| EA (Environmental Assessment) | 622 | 504 (81%) | 118 (19%) | ~116 (98%) |
| EIS (Environmental Impact Statement) | 794 | 509 (64%) | 285 (36%) | ~281 (99%) |
| Total | 22,279 | 10,644 (48%) | 11,635 (52%) | ~397 EA/EIS |
| 1 CE projects use legal land descriptions without coordinates, making county recovery infeasible. EA and EIS projects have lat/long coordinates that enable reverse geocoding. | ||||
The low county coverage for CE projects (46%) reflects their streamlined documentation standards, which often use legal land descriptions rather than explicit county identifiers, or that they simply don’t include easily recognizable geographic data. In contrast, nearly all EA and EIS projects missing county data (98.5%) or about 397 projects can be recovered through reverse geocoding using their existing lat/long coordinates. This would increase EA coverage from 81% to ~99% and EIS coverage from 64% to ~99%.
At the county level, Aiken, South Carolina, has a number of projects that are largely driven by nuclear projects at the Savannah River Site that were not marked for exclusion (because they were not tagged as “Waste Management”). Boundary, Idaho also has a high count of projects, likely driven by the national labs there as well.
Process Type by Location by Review Process
The following three maps show county-level project concentration by NEPA process type using a continuous gradient scale. Each map has its own legend calibrated to that process type’s data distribution. CE projects dominate the highest activity counties (particularly in South Carolina and Idaho), while EA and EIS projects show more dispersed, lower-intensity geographic patterns.
The following three maps (Figure 12, Figure 13, Figure 14) provide an alternative view using Jenks natural breaks classification. Unlike the continuous gradient above, Jenks classification groups counties into classes that mathematically highlight differences between groups1. Each map calculates its own classification breaks based on that process type’s data distribution, making it easier to identify distinct tiers of project activity within each category.
Deeper Dive into High Project Count Counties
This section examines the projects in counties with the highest project counts for each NEPA process type. The figures show technology distribution across the top 10 counties, while the tables provide a random sample of 20 projects from the top 2 counties. Full project lists are available in the Google Sheet.
Top Categorical Exclusion (CE) Counties
Figure 15 shows the technology distribution across the top 10 CE counties.
Table 4 shows a random sample of 20 projects from the two counties with the highest CE counts.
| Project Title | Technology | Location |
|---|---|---|
| Fiscal Year (FY)-14 Wireless Test Bed Fiber Optic Cable to Gate 1 and Experimental Breeder Reactor-I (EBR-I) Cell Sites | Broadband, Utilities, Waste Management, Electricity Transmission | Butte, ID |
| Remove Power from Disconnect 7.06 in Building 234-H Room 326 | Electricity Transmission, Utilities, Waste Management | Aiken, SC |
| Function Test Station Process Computer System (PCS) Replacement | Nuclear Technology, High Performance Computing and Advanced Computer Hardware and Software, Data Storage and Data Management | Aiken, SC |
| Benchtop Distillation and Recovery of Volatile Solvents | Research and Development, Waste Management, Biomass | Aiken, SC |
| Installation of Kurz Flowmeter in Plant Air System | Utilities | Aiken, SC |
| Excavation/Replacement of 218-H Cooling Tower Make-up Isolation Valve HQ-234000-DW-V-80.018 | Water Resources - Irrigation and Water Supply, Utilities, Manufacturing | Aiken, SC |
| Materials and Fuels Complex Temporary Office Trailers | Land Development - Other, Utilities, Water Resources - Irrigation and Water Supply, Waste Management | Butte, ID |
| 772-25B Renovation | Land Development - Other, Research and Development, Utilities | Aiken, SC |
| Design and Replace TEF Glovebox Panametrics and Teledyne with Manufacturer Recommended Model | Nuclear Technology | Aiken, SC |
| Rebuild Kamer Valve HTN.153F | Nuclear Technology, Manufacturing, Utilities | Aiken, SC |
| 703-46A Replace Fire Alarm System | Utilities | Aiken, SC |
| Repair of Sinkhole and Remove Grass from East of 234-H Main Side Air Handling Unit | Land Development - Other, Vegetation and Fuels Management, Nuclear Technology | Aiken, SC |
| Liteye CUAS Testing | Research and Development, Military and Defense, Cybersecurity, Aviation - Airports and Air Traffic, Land Development - Other, Utilities, Waste Management | Butte, ID |
| General Building Maintenance Activities in the SRTE Limited Area | Nuclear Technology, Routine Maintenance | Aiken, SC |
| Materials and Fuels Complex (MFC) Fire Water Replacement and Upgrades | Water Resources - Irrigation and Water Supply, Waste Management, Land Development - Other, Utilities, Electricity Transmission | Butte, ID |
| Central Facilities Area (CFA)-696 Compressed Air System Upgrade | Utilities, Manufacturing, Waste Management | Butte, ID |
| Replacement of Air Compressors - Building 775-A | Manufacturing, Nuclear Technology, Utilities | Aiken, SC |
| Providing electrical power to proposed SCDHEC air monitoring location for Environmental Baseline Monitoring for the project | Research and Development, Electricity Transmission | Aiken, SC |
| Unmanned Aerial System Testing | Aviation - Airports and Air Traffic, Research and Development, Electricity Transmission, Land Development - Other, Waste Management, Utilities | Butte, ID |
| Paint 253-1H Switchgear Exterior | Electricity Transmission | Aiken, SC |
Top Environmental Assessment (EA) Counties
Figure 16 shows the technology distribution across the top 10 EA counties.
Table 5 shows a random sample of 20 projects from the two counties with the highest EA counts.
| Project Title | Technology | Location |
|---|---|---|
| Easley Renewable Energy Project | Solar, Energy Storage, Electricity Transmission, Waste Management | Riverside, CA |
| IP Athos Renewable Energy Project 220-kV Generation Tie-Line Invasive Plant Management Integrated Weed Management Plan and Pesticide Use Proposal for Construction, Operation, and Maintenance Activities | Vegetation and Fuels Management, Electricity Transmission, Solar, Routine Maintenance, Ecosystem Management and Restoration, Threatened and Endangered Species Management | Riverside, CA |
| Arica Solar Project and Victory Pass Solar Project | Solar, Electricity Transmission | Riverside, CA |
| Riverside East Solar Energy Zone, Excavation Pits for Soil Profile Characterization | Research and Development, Solar | Riverside, CA |
| Black Rock Communications Tower and Power Line | Utilities, Broadband, Electricity Transmission | Mohave, AZ |
| Renewal of Happy Jack Rights-of-Way Grants | Utilities, Electricity Transmission, Broadband | Mohave, AZ |
| Desert Harvest Solar Project Integrated Weed Management Plan Implementation for Operations and Maintenance Activities | Solar, Vegetation and Fuels Management, Ecosystem Management and Restoration, Threatened and Endangered Species Management, Laws, Policies, Regulations, and Guidance | Riverside, CA |
| USGS Groundwater Monitoring Well | Water Resources - Other, Mining - Metals, Conventional Energy Production - Nuclear, Research and Development, Ecosystem Management and Restoration | Mohave, AZ |
| Indian Canyon Drive and Bridge Widening | Surface Transportation - Bridges, Surface Transportation - Other, Utilities | Riverside, CA |
| Andrews Farms Right-of-Way | Surface Transportation - Other, Utilities, Routine Maintenance | Mohave, AZ |
| Blythe Mesa Solar Project | Solar, Electricity Transmission | Riverside, CA |
| Sacramento Valley Rights-of-Way Reauthorizations | Electricity Transmission, Utilities, Routine Maintenance | Mohave, AZ |
| West Highway 93 Rights-of-Way Renewals | Electricity Transmission, Utilities | Mohave, AZ |
| Mount Perkins Communications Site - BLM | Utilities, Solar, Land Use or Forest Management Plan, Ecosystem Management and Restoration, Threatened and Endangered Species Management, Routine Maintenance | Mohave, AZ |
| Right-of-Way AZA 037286 | Utilities, Electricity Transmission, Routine Maintenance | Mohave, AZ |
| Crossman Peak Road Right-of-Way | Surface Transportation - Other, Routine Maintenance, Utilities | Mohave, AZ |
| Black Rock Communications Tower and Power Line | Utilities, Broadband, Electricity Transmission | Mohave, AZ |
| Arica and Victory Pass Solar Projects | Solar | Riverside, CA |
| Mesa Wind Repower Project | Wind, Onshore, Electricity Transmission, Waste Management | Riverside, CA |
| Pesticide Use Permit for Riviera Substation | Utilities, Electricity Transmission, Vegetation and Fuels Management, Routine Maintenance | Mohave, AZ |
Top Environmental Impact Statement (EIS) Counties
Figure 17 shows the technology distribution across the top 10 EIS counties.
Table 6 shows a random sample of 20 projects from the two counties with the highest EIS counts.
| Project Title | Technology | Location |
|---|---|---|
| Palen Solar Project | Solar | Riverside, CA |
| Southern Bighorn Solar Projects | Solar, Energy Storage, Electricity Transmission | Clark, NV |
| Chuckwalla Solar Projects | Solar, Energy Storage, Electricity Transmission | Clark, NV |
| Bonanza Solar Project | Solar, Threatened and Endangered Species Management, Ecosystem Management and Restoration, Land Use or Forest Management Plan | Clark, NV |
| Desert Harvest Solar Project | Solar, Electricity Transmission, Land Use or Forest Management Plan | Riverside, CA |
| Desert Quartzite Solar Project | Solar, Electricity Transmission | Riverside, CA |
| Searchlight Wind Energy Project | Wind, Onshore, Electricity Transmission, Laws, Policies, Regulations, and Guidance | Clark, NV |
| Searchlight Wind Energy Project | Wind, Onshore, Electricity Transmission | Clark, NV |
| Silver State Solar South Project and Proposed Las Vegas Field Office Resource Management Plan Amendment | Solar, Land Use or Forest Management Plan | Clark, NV |
| Crescent Peak Wind Energy Project | Wind, Onshore, Electricity Transmission | Clark, NV |
| Modified Blythe Solar Power Project | Solar, Electricity Transmission | Riverside, CA |
| Arrow Canyon Solar Project | Solar, Energy Storage, Electricity Transmission | Clark, NV |
| Bonanza Solar Project | Solar, Energy Storage, Electricity Transmission, Land Use or Forest Management Plan | Clark, NV |
| Rough Hat Clark Solar Project, Clark County, Nevada | Solar, Energy Storage, Electricity Transmission | Clark, NV |
| McCoy Solar Energy Project | Solar, Land Use or Forest Management Plan, Laws, Policies, Regulations, and Guidance, Electricity Transmission | Riverside, CA |
| Gemini Solar Project | Solar, Electricity Transmission, Land Use or Forest Management Plan, Laws, Policies, Regulations, and Guidance | Clark, NV |
| Rice Solar Energy Project, Riverside County, California | Solar, Electricity Transmission | Riverside, CA |
| Crimson Solar Project | Solar, Electricity Transmission, Land Use or Forest Management Plan | Riverside, CA |
| Gemini Solar Project | Solar, Electricity Transmission | Clark, NV |
| Yahthumb Solar Project | Solar, Energy Storage, Electricity Transmission | Clark, NV |
Report generated 2026-03-18 | NEPA Decarbonization Technologies Analysis
Footnotes
It does this by minimizing within-class variance and maximize between-class differences↩︎