Crews Rappel Washington Monument

Structural engineers are rappelling on the outside of the Washington Monument Wednesday. They are surveying damage to the structure caused by the August 23 earthquake. The work was postponed early Wednesday morning due to thunderstorms, but the dozen-man team has since resumed their efforts.

The team did begin rappelling down the monument Tuesday, and the investigation was supposed to happen then, but it was called off then as well because of thunderstorms and dangerous lightning. Engineers have already set up equipment and protective barriers around the monument's lightning rods.

Inside the monument are climbing experts monitoring the pulleys and anchors that fasten the rappelling system that circles the uppermost portion of the monument.  The climbers are equipped with mallets, masonry tools, collection bags, digital cameras and even an iPad. 

Weather updates are relayed by radio to the four climbers, two men and two women, on the outside. Carol Johnson, with the U.S. Park Service, says climbers will cease work immediately if an electrical storm approaches or winds exceed 25 mph. They are able to work in the rain, but it is up to the discretion of the climbers.

Each stone has been catalogued and surveyed during the 1999-2000 scaffolding, and workers will be looking at every individual stone for damage.

The tallest structure in the District -- and one of its most popular tourist attractions, has been closed since the 5.8 magnitude temblor damaged its dome.

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