TABLE OF CONTENTS 



Page 



LIST OF TABLES v 



LIST OF FIGURES vii 



EXECUTIVE SUMMARY x 



1.0 INTRODUCTION 1 



1.1 Background 1 



1.2 Seawolf Disposal Mound 6 



1.2.1 U.S. Navy Seawolf Disposal Activity 6 



1.3 Monitoring Activity 9 



1.3.1 September 1997 Monitoring Survey 9 



1.3.2 July 1998 Monitoring Survey 10 



2.0 METHODS 11 



2.1 Bathymetry and Navigation 11 



2.1.1 1997 and 1998 Survey Activity 11 



2.1.2 Bathymetric Data Collection 13 



2.1.3 Bathymetric Data Processing 13 



2.2 Sediment Profile Photography 15 



2.2.1 Seawolf Disposal Mound 20 



2.2.2 NLDS Reference Areas 24 



2.3 Benthic Community Sampling 24 



2.3.1 Sediment Grab Sampling 24 



2.3.2 Laboratory Analysis 27 



2.4 Sediment Cores 27 



2.4.1 Field Collections 28 



2.4.2 Sediment Sampling 32 



2.4.3 Laboratory Analysis Methods 32 



2.4.4 Quality Assurance/Quality Control 36 



3.0 RESULTS 42 



3.1 Seawolf Mound 42 



3.1.1 Bathymetry 42 



3.1.2 REMOTS® Sediment-Profile Photography 57 



3.1.3 Benthic Community Analysis 69 



3.1.4 Sediment Coring 76 



3.2 NLDS Reference Areas 102 



4.0 DISCUSSION 105 



4.1 Historical Disposal and Biological Response at the NLDS 105 



4.2 Seawolf Disposal Mound 107 



4.2.1 Topographic Changes of the Seawolf Mound 108 



4.2.2 Benthic Community Recolonization 109 



