21 



Stage III taxa require more time to become established than the pioneering Stage I 

 taxa. These invertebrates are infaunal, and many feed at depth in a head-down orientation 

 (Rhoads and Germano 1982, 1986). Disposal of Boston Blue Clay at MBDS had been 

 occurring for three months at the time of the survey. Once the material has remained 

 undisturbed on the seafloor for a period of time, colonization is expected to begin, as was 

 seen with the pioneering Stage I taxa on Blue Clay around the disposal mound center. Stage 

 III taxa are likely to have burrowed up through sequential, thin layers of dredged material at 

 stations located further from the center (Germano and Rhoads 1984). 



The colonization pattern predicted for the reference areas, Stage III taxa, was 

 confirmed by the REMOTS® analyses, indicating that the reference areas were not subject to 

 any disturbance or stress. For both the 1992 and the 1990 surveys, Stage III taxa were 

 present at all reference stations (Germano, Parker, and Charles 1994). Stage III taxa 

 generally represent high-order successional stages typically found in low disturbance regimes 

 (Rhoads and Germano 1982, 1986). 



The rapid rate of recolonization over the disposal site shows that these intense 

 storms, particularly the 100-year Halloween Storm, did not severely affect the stability of the 

 site or the benthic environment. There was no evidence at the reference areas or at the 

 disposal site of any notable disruption to the benthic environment due to Hurricane Bob or 

 the Halloween Storm. It was predicted that 43 knot winds for 12 hours could cause the 

 resuspension of material and affect the stability of the site (Hubbard et al. 1988). The 

 Halloween Storm generated 40 knot winds over 1 14 hours. This storm, which represented a 

 potential worst-case condition, did not severely affect the site. While it is likely that there 

 was some resuspension of bottom sedunents, it is clear that the effects from a storm of this 

 magnitude were less than mathematically predicted. Since the storm exceeded the 

 requirement for ideal storm set up to impact the bottom, without exhibiting impact, these 

 results reinforce the management assumptions that the Massachusetts Bay Disposal Site is a 

 stable site for containment of disposed dredged material. 



Monitoring Cruise at the Massachusetts Bay Disposal Site. March 31 - April 4, 1992 



