SRNL, A Area (copy)

Pictured is the Savannah River National Laboratory, which is located at the Savannah River Site. SRS is about 30 minutes south of Aiken.

Officials at the Savannah River Site, a sprawling nuclear reserve south of Aiken and about 135 miles northwest of Charleston, are closely watching Hurricane Dorian, now a Category 2, as it lumbers toward the South Carolina and Georgia coasts.

The Savannah River Site as of early Tuesday afternoon was operating at OPCON 2, a designation that requires the site be ready to significantly reduce staffing on short notice. Employees, though, are currently reporting to work as normal.

Dorian's impact to the site itself was predicted to be "relatively minor," according to an advisory sent to workers Monday. A U.S. Department of Energy spokesperson on Tuesday morning said there have been "no impacts to us yet."

The employee memo was drafted when the hurricane was a fearsome Category 5 and more than 100 miles from West Palm Beach, Fla.

The Energy Department's nuclear facilities, though aging, are built with natural disasters and potential catastrophes in mind.

"Federal regulations require these facilities be able to withstand extreme natural events, including hurricanes and floods," an Energy Department spokesperson said last year ahead of Hurricane Florence.

"The Department of Energy takes a very measured approach when it comes to the safety of the public, our workers and the environment," the spokesperson continued.

The Savannah River Site – home to millions of gallons of nuclear waste and metric tons of plutonium – has been looped in with the S.C. Emergency Management Division, participating in twice-daily calls.

Hurricane Michael, which hit the CSRA in October as a tropical storm, left the site largely unscathed. Some loss of power was reported, as were downed trees. "Minimal" damage to some administrative buildings was recorded, as well, but no operating or nuclear facilities were threatened, the Energy Department spokesperson said at the time.

The seemingly most pressing concern laid out in the Monday message to employees was a spike in traffic around the site as coastal residents began to head inland. S.C. Gov. Henry McMaster on Sunday ordered the evacuation of the coast. Those evacuations began Monday.

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