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Defense Budget: Obligations of Overseas Contingency Operations Funding for Operation and Maintenance Base Requirements

GAO-18-202R Published: Jan 10, 2018. Publicly Released: Jan 10, 2018.
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What GAO Found

The Department of Defense (DOD) reported obligating the $9.1 billion that Congress authorized in the National Defense Authorization Act for Fiscal Year 2016 as operation and maintenance (O&M) overseas contingency operations (OCO) funding for base requirements. These obligations were largely for base programs and activities, such as for headquarters, maintenance, and transportation costs. O&M base requirements encompass the continuing annual costs of DOD’s routine operations that would be incurred whether or not a contingency operation took place—including operating support for installations, training and education, civilian personnel, maintenance, contracted services, and defense health. In the Consolidated Appropriations Act, 2016, and the explanatory statement accompanying it, Congress subsequently appropriated $8.6 billion of the $9.1 billion authorized, as base funds rather than as OCO funds, while the remaining $500 million was appropriated as OCO funds for base requirements. DOD reported obligating these funds largely as was designated in the explanatory statement accompanying the Consolidated Appropriations Act, 2016.

Why GAO Did This Study

Since September 2001, Congress has appropriated approximately $1.7 trillion to DOD to fund OCO. On occasion, Congress has directed that OCO appropriations be used to support O&M base requirements. The National Defense Authorization Act for Fiscal Year 2016 authorized $9.1 billion of OCO appropriations to be made available for the support of specific O&M base requirements. The act also included a provision for GAO to report on how all funds authorized for base requirements were ultimately obligated by DOD. This report describes how DOD obligated the $9.1 billion in OCO appropriations that Congress authorized for base requirements in fiscal year 2016.

In order to determine how DOD obligated the $9.1 billion, GAO compared the O&M OCO amounts authorized for each O&M subactivity group in the National Defense Authorization Act for Fiscal Year 2016 with the amounts that Congress designated for those subactivity groups in the Consolidated Appropriations Act, 2016. GAO then compared those designated amounts with data provided by the military services and from DOD’s execution reports and budget materials on the amounts obligated by subactivity group.


GAO did not make any recommendations in the report and DOD did not have any comments on this report. 

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Appropriation accountsBase operationsBudget appropriationsBudget authorityBudget obligationsBudget requestsDefense budgetsMilitary basesMilitary readinessOperations and maintenanceOverseas contingency operations