Reprint or republication of any of this material 

 shall give appropriate credit to the U.S. Army Coastal 

 Engineering Research Center. 



Limited free distribution within the United States 

 of single copies of this publication has been made by 

 this Center. Additional copies are available from: 



National Technical Information Service 

 ATTN: Operations Division 

 5285 Port Royal Road 

 Springfield, Virginia 22161 



Contents of this report are not to be used for 

 advertising, publication, or promotional purposes. 

 Citation of trade names does not constitute an official 

 endorsement or approval of the use of such commercial 

 products. 



The findings in this report are not to be construed 

 as an official Department of the Army position unless 

 so designated by other authorized documents. 



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