An early study by the Corps of Engineers in evaluating techniques for 

 transferring offshore sand to the beach is described by Mauriello (1967). 

 This experiment at Sea Girt, New Jersey, involved dredging of 191,000 cubic 

 meters of sand by the hopper dredge, Geothats, at a location 3.2 kilometers 

 offshore from the beach segment to be restored. The loaded dredge, which had 

 a pumpout capability, docked alongside an anchored barge and the sand was 

 pumped ashore through a submerged pipeline. 



At Redondo Beach, California, in 1967-68, the U.S. Army Engineer District, 

 Los Angeles, contracted dredging of more than 1.1 million cubic meters of sand 

 from offshore depths of 12 meters and transferring the sand to the beach. 

 These operations, as well as others conducted in open-ocean environments in 

 Long Island Sound and along the gulf and Atlantic coasts, have demonstrated 

 the feasibility of using offshore marine and lake deposits for beach nourish- 

 ment operations. 



Along the Connecticut shore alone, about 32 kilometers of beaches have 

 been filled and nourished from about 1940 to 1970 by using hydraulic dredges 

 to pump material to the beaches from offshore source areas (McCabe, 1970). 

 The projects were cooperative efforts between the Corps of Engineers, the 

 State of Connecticut, and the individual towns along the shore. In some cases 

 the fill sand was derived from navigation channel dredging, but more often it 

 was obtained from borrow pits close to the project beaches. 



2. Field and Laboratory Procedures. 



The exploration phase of the ICONS program uses seismic reflection pro- 

 filing supplemented by cores of the bottom sediment. Supporting data for the 

 studies are obtained from National Ocean Survey (NOS) hydrographic smooth 

 sheets and from literature sources. Planning, seismic reflection profiling, 

 coring, positioning, and analysis of sediment obtained in the cores are 

 detailed in Williams and Duane (1974). A brief description of these tech- 

 niques follows : 



a. Planning. Survey tracklines were laid out initially in grid or 

 reconnaissance lines. A grid pattern (line spacing of about 4 to 5 kilo- 

 meters) was used to cover areas where a more detailed development of bottom 

 and subbottom conditions was desired. 



Selection of core sites was based on a continuing review of the seismic 

 profiles as they became available during the survey. This procedure allowed 

 core-site selection based on the best information available; it also permitted 

 the coring to be completed in one area before coring was started at another 

 site. 



b. Seismic Reflection Profiling . Seismic reflection profiling is a 

 technique for delineating subbottom structures and bedding planes in sediments 

 and rocks underlying water-covered areas. Continuous reflections are obtained 

 by generating repetitive, high-energy sound pulses underwater near the water 

 surface and recording "echoes" reflected from the bottom-water interface, and 

 subbottom interfaces beween acoustically dissimilar materials. In general, 

 compositional and physical properties which commonly differentiate sediments 

 and rocks also produce acoustic contrasts. Thus, an acoustic profile is 

 roughly comparable to a geologic cross section. 



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