| 1 | FLUOR-BWXT PORTSMOUTH LLC | $4,465,824,270 | 1 | $4,465,824,270 | Aug 16, 2010 | Department of Energy |
| 2 | SAVANNAH RIVER MISSION COMPLETION, LLC | $2,965,438,975 | 4 | $741,359,744 | Oct 01, 2023 | Department of Energy |
| 3 | CENTRAL PLATEAU CLEANUP COMPANY, LLC | $2,700,752,323 | 3 | $900,250,774 | Oct 01, 2024 | Department of Energy |
| 4 | UNITED CLEANUP OAK RIDGE LLC | $2,429,373,908 | 1 | $2,429,373,908 | May 17, 2023 | Department of Energy |
| 5 | IDAHO ENVIRONMENTAL COALITION LLC | $1,628,766,368 | 1 | $1,628,766,368 | Oct 01, 2023 | Department of Energy |
| 6 | CH2M HILL BWXT WEST VALLEY, LLC | $990,004,958 | 1 | $990,004,958 | Jul 01, 2011 | Department of Energy |
| 7 | SEVENSON ENVIRONMENTAL SERVICES, INC. | $605,489,172 | 15 | $40,365,945 | Mar 17, 2026 | Department of Defense |
| 8 | HANFORD LABORATORY MANAGEMENT AND INTEGRATI… | $523,182,823 | 1 | $523,182,823 | Sep 29, 2020 | Department of Energy |
| 9 | NORTH WIND PORTAGE, INC. | $451,613,604 | 4 | $112,903,401 | May 02, 2024 | Department of Energy |
| 10 | EA ENGINEERING, SCIENCE, AND TECHNOLOGY, IN… | $381,170,824 | 66 | $5,775,316 | Jul 22, 2026 | Environmental Protection … |
| 11 | TETRA TECH, INC. | $343,292,650 | 15 | $22,886,177 | Jun 02, 2026 | Environmental Protection … |
| 12 | RSI ENTECH, LLC | $308,796,303 | 4 | $77,199,076 | Oct 30, 2025 | Department of Energy |
