SRS Sign, UK Uranium (copy)

The Savannah River Site is a 310-square-mile nuclear complex located south of Aiken.

The U.S. Department of Energy has extended the contract of the Savannah River Site's current paramilitary security force.

Centerra-SRS will now stay on the job through Feb. 7, 2020, according to a Friday evening announcement from the Energy Department. The team's contract was otherwise set to expire Monday.

The contract addendum – four months – has an estimated cost of $35.8 million.

The Savannah River Site security contractor is charged with protecting the site and its personnel around the clock, as well as conducting police work and investigations, among other duties.

Centerra-SRS, a subsidiary of Centerra Group, has previously received excellent evaluations.

The team recently earned $3.1 million for the contract period ending March 31. That's 96% marked success, according to a related performance scorecard.

The Energy Department in late August signaled its intent to continue contracting Centerra-SRS. A post saying as much was made to Federal Business Opportunities, a government jobs website.

The extension comes as the Energy Department works through awarding a completely new security contract – one worth upward of $1 billion.

"To DOE's knowledge, only Centerra has the requisite knowledge, experience and capabilities to provide these critical highly specialized services without interruption during the acquisition cycle for transition to a new contract," reads the Energy Department's Friday notice.

More than one proposal for the new site security contract has been submitted, according to remarks made by Michael Budney, the Savannah River Site manager.

Colin Demarest covers the Savannah River Site, the U.S. Department of Energy, the National Nuclear Security Administration and government in general. Follow him on Twitter: @demarest_colin