REMOTE SENSING SURVEY OF 300-FOOT BUFFER AND DIVER IDENTIFICATION OF MAGNETIC ANOMALIES, TYBEE ISLAND BEACH EROSION CONTROL PROJECT, CHATHAM COUNTY, GEORGIA, 2015 RENOURISHMENT

The U.S. Army Corps of Engineers, Savannah District is proposing to perform periodic renourishment to the Tybee Island Beach Erosion Control Project, Chatham County, Georgia. Approximately 1,400,000 cubic yards of material will be placed on the beach within the limits of the Federal project. Located at the mouth of the Savannah River and comprised of the ocean facing beaches on Tybee Island, this area includes Oceanfront North Beach from the North End Groin to Oceanview Court; 2nd Street from 11th Street to the South End Groin; and Back River/Tybee Creek from the southern tip of the Groin Field to Inlet Avenue. In order to assist the Savannah District with meeting compliance requirements related to the National Environmental Policy Act, Panamerican, under subcontract to DCA/GEC A Joint Venture, LLC, conducted a comprehensive submerged cultural resources investigation of the Project Area in response to U.S. Army Corps of Engineers’ Scope of Work entitled Remote Sensing Survey of 300-foot Buffer and Diver Identification of Magnetic Anomalies, Tybee Island Beach Erosion Control Project, Chatham County, Georgia, 2015 Renourishment.

The project consisted of archival research, a remote sensing refinement survey and diver investigation of the potentially significant targets, and a comprehensive remote sensing survey of the a 300-foot wide buffer on two sides of the borrow area, these areas being employed for dredge material. Both refinement survey and survey of the 300-foot wide Buffer Area utilized a magnetometer, side scan sonar and sub bottom profiler system.

Fieldwork was conducted September 1 through 14, 2013. Analysis of remote sensing survey data of the 300-foot Buffer Area indicated an absence of magnetic, side scan, and sub bottom targets. Additionally, investigation of the anomalies was negative with the majority considered to consist of modern point source debris, possibly wire rope, and are not indicative of potentially significant historic resources (i.e., a shipwreck), and no further investigations of the targets are recommended. It should be stated that only a few of the previously recorded targets are in their respective 2008 locations. The majority of the targets are in new locations, and several are no longer extant, indicating that they have either moved or in some cases been removed, either by natural or human activity. Shrimp trawling activity in the area is the most obvious cause for this observation, although storm activity cannot be discounted.