131 



in the future. 



On the other hand, the monitoring concerns that have been suggested for 

 the proposed San Francisco Bay Deep Water Dredged Material Disposal Site do 

 include biological effects of approved dumping. This would be a welcome 

 change, if EPA Region IX does actually implement a monitoring plan that 

 assesses the effects upon the biological community of dumping dredged materials 

 that may be contaminated at whatever site is ultimately designated. However, 

 while we feel that monitoring is essential wherever sediments of questionable 

 quality or known contamination are dumped, we do not view the disposal of 

 contaminated materials at an open water dump site as consistent with the intent of 

 the MPRSA. 



b. Past capping of contaminated sediments has revealed flaws and limits in 

 being an effective mitigative measure. 



In 1980. an "experiment" was initiated by the New York District of the 

 Corps (NYD) to evaluate how effective a cap would be at reducing possible 

 environmental impact by covering and isolating contaminated dredge material. 

 This was decided upon because the NYD determined that .sediments from several 

 dredging projects had the potential to cause contaminant bioaccumulation in test 

 organisms, suggesting that the material did not comply with ocean dumping 

 criteria. Consequently, a decision was made to deposit the sediments into the 

 most unimpacted quadrant of the Mud Dump Site, the southeast quadrant, and cap 

 the material with silty material from the Bronx River and Westchester Creek and 

 sand from the Ambrose Channel. Also, the NYD decided to study the effect of 

 capping at the MDS because "the overall efficacy of capping as a mitigating 

 measure had not been proven. " I? Approximately 500,000 cubic yards of 

 contaminated sediments were dumped in the southeast quadrant of the Mud Dump 

 Site and covered with over 1 million cubic yards of fine-grained and sandy 

 material. This mound became referred to as the Experimental Mud Dump 

 (EMD). 



By 1982, several studies had been conducted to determine "the potential for 

 placing a cap at the experimental Mud Dump Site and to determine reductions in 

 environmental impacts related to capping." The reports submitted to the Corps 



l5 Joseph M. O'Connor and Susan G. O'Connor. October 1983. Evaluation 

 of the 1980 Capping Operations at the Experimental Mud Dump Site. New York 

 Bight Apex ., (p.35) 



