APPENDIX A 

 PRELIMINARY TESTS OF SAMPLING DEVICES 



The surf zone of the ocean beach was difficult to sample. The 

 shallow water and the severe turbulence of the high-energy beach 

 precluded the use of a boat or a research vessel, and thus eliminated 

 most bottom sampling gear used in marine benthic sampling. 



Preliminary tests were conducted on two grab samplers which were 

 light enough to handle in the surf zone. A petit ponar grab sampler 

 was tested in the surf zone at Sandbridge, Virginia, on a beach similar 

 to the beach at the FRF site. This grab penetrated less than 3 

 centimeters in areas of compact sand, and produced samples which were 

 shallow and inadequate for the analysis. In the surf zone, the grab 

 turned over as each wave passed. Adequate samples were taken in the 

 coarse material of the surf zone when the grab was dropped, closed, and 

 retrieved between passing waves, but this restrictive sampling pro- 

 cedure made the grab inefficient. 



A pole-mounted Echman grab sampler was tested, but was unsuitable. 

 Although it was stable in the surf, it could not penetrate hard-packed 

 sand. The jaws jammed open on shells and rocks, and usually lost part 

 of the sample. During periods of severe wave conditions, the sampler 

 was dangerous to handle in the surf. 



Several lightweight, commercially available corers with sample 

 retention devices were tested in the surf zone. However, samples taken 

 by the corer were small (generally less than 15 square centimeters) 

 and unsuitable for the study. 



The device selected for use in this study is described in Section II, 

 2 of the text. 



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