One of the most recognizable monuments in all of Washington, D.C., is currently the subject of an in-depth survey to determine if there have been any leveling issues within the National Mall caused by the August 2011 earthquake that hit the eastern seaboard.
A group of experts from the National Oceanic Atmospheric Administration's (NOAA's) National Geodetic Survey (NGS) are currently performing a leveling survey on the Washington Monument to learn what kind of seismic shift, if any, occurred to the ground beneath the monument. Early analyses show there was no significant vertical motion, but even slight variances in topography could affect repair plans.
Later this year, NOAA surveyors will use GPS to take measurements from the top of the monument to determine if the structure has tilted at all due to the rare 5.8-magnitude earthquake.
Engineering firms that the National Park Service (NPS) has under contract will repair the stone structure. These firms will use the findings of the leveling survey to help complete the planned $15 million restoration.
The engineering and repair crews working to finish the restoration of the monument will need to follow the standards set by the Occupational Safety and Health Administration (OSHA), including the use of appropriate safety products, such as hard hats, safety glasses, and work gloves.