[en] Martin Marietta Energy Systems, Inc. (Energy Systems), manages and operates the Oak Ridge National Laboratory (ORNL), Oak Ridge, Tennessee, under a cost-plus-award-fee contract administered by the Department of Energy's (DOE) Oak Ridge Field office (Field Office). Energy Systems' environmental restoration program is responsible for eliminating or reducing to prescribed safe levels the risks to the environment or to human health and safety posed by inactive and surplus sites and facilities that have been contaminated with radioactive, hazardous, or mixed wastes. Energy Systems subcontracted to perform the remedial investigation and feasibility study (RI/FS) at ORNL. The objective of our audit was to determine if the RI/FS at ORNL had been implemented in a manner that ensured accomplishment of the goals and objectives of the DOE Environmental Restoration Program. The audit disclosed that the subcontractor did not fully meet its contractual requirements. Specifically, environmental data produced by the subcontractor is of questionable value for meeting its contractual requirement to provide data supporting permanent remedial action. This condition occurred because neither the subcontractor nor Energy Systems adequately implemented all essential management controls, and neither Energy Systems nor DOE provided adequate contract administration. As a result, DOE has received little value for its RI/FS expenditures. We have recommended that DOE determine the allowability of an estimated $45 million of subcontractor RI/FS cost at ORNL, plus the cost of Energy Systems administering the subcontract. Furthermore, DOE will continue to pay unnecessary costs and experience cost growth and project delays until effective project management controls are implemented