Post-award changes to the Energy Department's nuclear-cleanup task orders produced more than $500 million in cost growth, according to a Government Accountability Office report released July 29.
The department's Office of Environmental Management had awarded 57 task orders across nine contracts under its End State Contract Model as of March 31, 2025. The model is meant to divide cleanup into outcome-based assignments with clearer costs, schedules and environmental results.
Only 29 of the 57 orders defined an end state. The remainder covered support work or cleanup that did not yet have a defined end state, limiting how directly the model's outcome promise applied across the portfolio.
GAO closely reviewed 19 task orders. Of nine completed orders, three lacked defined end states and six defined them but achieved them inconsistently. Three orders reduced or carried unfinished work forward after award, so contractors completed less work against modified outcomes.
The auditors said inconsistent documentation made it unclear how much those changes reduced costs. Headquarters also lacked adequate oversight to determine whether sites were consistently defining and achieving the intended cleanup results.
Cost growth varied sharply among selected orders. GAO listed about $216.7 million for an Oak Ridge phase-in order and about $75.8 million for Nevada environmental operations, while percentage increases exceeded 100% on two smaller assignments.
Contract form mattered. Orders that shifted more cost risk to contractors generally experienced less growth, while DOE more often used structures that left greater risk with the government and those orders had the largest increases.
GAO made six recommendations covering data quality, headquarters oversight, environmental-risk planning, root-cause analysis, cost estimates and deadlines for finalizing initially undefinitized orders. DOE agreed with five and partially agreed with one.
The report measures increases in contract value, not a finding that every added dollar was unnecessary. Scope changes, cleanup discoveries and valid new requirements can alter costs, but GAO concluded the department needs stronger controls to know whether the model is delivering its promised outcomes.