3.1.2.4 July 1998 Survey 82 



3.1.3 August 1 992 Dissolved Oxygen Measurements 90 



3.2 USCGA Disposal Mound 90 



3.2.1 Bathymetry 90 



3.2.2 REMOTS® Sediment-Profile Photography 90 



3.3 NL-94 Disposal Mound 98 



3.3.1 Bathymetry 98 



3.3.2 REMOTS® Sediment-Profile Photography 98 



3.3.2.1 August 1995 Survey 98 



3.3.2.2 September 1997 Survey 106 



3.4 Northern Region 110 



3.4.1 1997 Master Bathymetric Survey 110 



3.4.2 NLDS Northern Region 115 



3.4.2.1 Bathymetry 115 



3.4.2.2 REMOTS® Sediment-Profile Photography 115 



3.5 NL-92 Disposal Mound 122 



3.6 NLDS Reference Areas 122 



3.6.1 August 1992 Survey 122 



3.6.2 August 1995 Survey 125 



3.6.3 September 1997 Survey 128 



3.6.4 July 1998 Survey 129 



4.0 DISCUSSION 133 



4. 1 Topography and Evidence of Historical Disposal at the NLDS 133 



4.2 Biological Response to Disposal at the NLDS 134 



4.2. 1 Evidence of Low Dissolved Oxygen 136 



4.3 Capping of the Dow/Stonington Disposal Mound 138 



4.3.1 Benthic Recolonization 138 



4.3.2 Sediment Distribution and Characterization 139 



4.3 USCGA Mound 141 



4.5 NL-94 Mound 144 



4.6 Northern Region 146 



5.0 CONCLUSIONS AND RECOMMENDATIONS 148 



5.1 Overview of Monitoring 148 



5.2 Dow/Stonington and NL-91 Mound « .• 149 



5.3 USCGAMound 150 



5.4 NL-94 Mound 151 



5.5 Northern Region 151 



5.6 Recommendations 151 



6.0 REFERENCES 153 



