The following two letters used as part of the number designating technical reports of research published under the Repati>, 

 Evaluation. Maintenance, and Rehabilitation (REMR) Research Program identify the problem area under which the report 

 was prepared: 





Problem Area 



EM 



Problem Area 



cs 



Concrete and Steel Structures 



Electrical and Mechanical 



GT 



Geotechnical 



El 



Environmental Impacts 



HY 



Hydraulics 



OM 



Operations Management 



CO Coastal 



Destroy this report when no longer needed. Do not return 

 it to the originator. 



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. 



The 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. 



■IT i 



i°" 

 = '=° 



= ° i 



mC3 



COVER PHOTOS: ' ^_^ „ 



TOP — Concrete breakwater at Depoe Bay, Oregon (1969). 



BOTTOM — Rubble-mound jetties at Tillamook, Oregon (1979). 



