WASHINGTON – Repairs to the Washington Monument will require massive scaffolding to be built around the 555-foot obelisk and may keep it closed into 2014 after it was damaged by an earthquake last year, the National Park Service said Monday.

A damage assessment by engineers who inspected the stone structure by rappelling from the top last September found scaffolding is necessary to provide workers access to the top of the monument, said park service spokeswoman Carol Johnson. The engineers determined the heaviest damage is between 475 feet and 530 feet on the structure, but panels are damaged from top to bottom.

"It is difficult to get to, and it's difficult to repair," Johnson said. "Panels stressed during the earthquake will have to have anchors installed."