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 

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 ATTN: Operations Division 

 5285 Port Royal Road 

 Springjield, 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. 



