TABLE OF CONTENTS 



Page 



LIST OF TABLES iv 



LIST OF FIGURES v 



EXECUTIVE SUMMARY vi 



1.0 INTRODUCTION 1 



1 . 1 The Boston Harbor Navigation and Improvement Project 1 



1 .2 Background to the Conley Terminal Project 4 



L2.1 Excavation of the CAD Cell 4 



1 .2.2 Dredged Material Disposal Operations 4 



1.2.3 Capping Operations 7 



1.3 CAD Cell Monitoring Survey 7 



2.0 SURVEY METHODS 9 



2.1 Navigation 9 



2.2 Vibracore Survey 9 



2.2.1 Coring Operations 9 



2.2.2 Vibracore Collection and Processing 10 



2.3 Acoustic Survey Operations 12 



2.3.1 Bathymetric Data Collection and Analysis 12 



2.3.2 Subbottom Data Collection and Analysis 13 



2.3.3 Sidescan Data Collection and Analysis 14 



2.4 Videosled Survey 14 



3.0 RESULTS 15 



3.1 Side-scan Sonar Results 15 



3.2 Bathymetric Results 15 



3.3 Vibracore Results 19 



3.4 Subbottom Results 25 



^ 3.5 Video Results 29 



4.0 DISCUSSION 32 



4. 1 Topography and Texture of the Sediment Surface of the CAD Cell 32 



4.2 Thickness of the Sand Cap 32 



4.3 Implications of Cap/Dredged Material Mixing 33 



4.4 Consolidation of the Maintenance Material 34 



4 . 5 Implications of Erosion from the Unsupported Cell Walls 34 



