The Dahlgren Navy base has a big impact on the region's economy, mainly from jobs and an enormous payroll.
The King George County base, according to an updated economic profile, is one of the region's largest employers, with about 7,600 workers.
Of those, 4,729 are civilian employees working for nearly 20 separate military commands and supporting organizations at the installation along the Potomac River.
Most of those work at Dahlgren's eight tenant commands.
Another 2,500 work for defense contractors that do business with the installation—companies such as General Atomics and BAE Systems, which have built launcher prototypes for a planned electromagnetic rail gun under development at Dahlgren.
Another 381 workers are military personnel stationed on base.
The economic impact summary covers the last fiscal year, which ran through September 2012.
It's unclear how the impact of the automatic spending cuts of sequestration on the Navy will affect the local economy and next year's report.
Last year, the installation pumped an estimated $1.1 billion into the economy through payroll and defense contracts, according to the report.
The combined payroll during the fiscal year for federal civilian workers and military employees alone was more than $511 million. Another $594 million in defense contracts went to companies in Virginia's Planning District 16, which includes Fredericksburg and the counties of Stafford, Spotsylvania, King George, Caroline.
The report also offers some insight as to where the workforce is distributed.
Of the civil servants and military working for the base, 1,770—40 percent—live in King George.
Spotsylvania is next highest, with 769 (17 percent); followed by Fredericksburg, 481 (11 percent); and Stafford County, 474 (10.7 percent.) The rest come from outlying counties in Virginia and Maryland.
Naval Support Facility Dahlgren began in 1918 as an extension of the Indian Head Proving Ground in southern Maryland. Over the years, it has become one of the Navy's key research and development sites, and in more recent years, a hub for developing missile-defense technology.