Audit: DOE-OIG-26-23

March 12, 2026

Consolidated Nuclear Security, LLC's Statement of Cost Incurred and Claimed for Fiscal Years 2016 Through 2018 Under Contract No. DE-NA0001942

The Office of Inspector General initiated this audit to review the $5,872,733,964 of costs claimed by Consolidated Nuclear Security, LLC (CNS) to manage and operate the Pantex Plant and the Y-12 National Security Complex for fiscal years (FY) 2016 through 2018.

CNS managed and operated both the Pantex Plant and the Y-12 National Security Complex as a management and operating contractor for the Department of Energy's National Nuclear Security Administration.

Specifically, the audit objective was to determine if costs charged to Department Contract No. DE-NA0001942 for FYs 2016 through 2018 were allowable, allocable, and reasonable in accordance with appliable laws, regulations, and contract terms.

We identified one noncompliance and one control deficiency. We questioned approximately $324,000 of costs claimed by CNS in its Statement of Cost Incurred and Claimed in FYs 2016 and 2017 for unworked overtime due to an administrative error. We also found that CNS improperly classified subcontracts as firm-fixed-price due to control deficiencies in subcontract administration.

To address the issues identified in this report, we made two recommendations that, if fully implemented, should reduce the risk of reimbursing unallowable costs. Further, we recommend that CNS work with the contracting officer to resolve the questioned costs identified in this report.

CNS concurred with our recommendations; however, it did not agree with all the information presented in the report specifically related to an investigative matter.

• DOE-OIG-26-23.pdf (419.51 KB)