Information on baseline conditions at the site, including 

 chemical and physical characteristics, exists from recently 

 completed studies. Between 1984 and 1986, EPA conducted 5 

 baseline studies at the site. The data that were collected were 

 used to develop an updated monitoring plan and were used as the 

 baseline for comparison of more recently gathered data at the 

 DMSDS. 



Since 1986, when sludge dumpers first began utilizing the 

 DMSDS, EPA has conducted semiannual surveys at the site to 

 determine the fate and effect of the sludge being dumped. In 

 addition to field observations of sludge plume behavior, waste 

 characterizations have been performed on sludge samples collected 

 both at the site and at the individual treatment plants. 



9 . 4 Appendix 4. Questions and Answers about Shell Disease 



During the Working Group discussions, it became apparent 

 that specific responses to many questions about shell disease 

 could be useful to readers of the report. We have selected some 

 that seem of most concern, and have provided a brief summary of 

 information about each. 



° What specific microorganisms are associated with 

 shell disease in New York Bight crustaceans ? 



Several species of bacteria and fungi have 

 been identified from shell lesions of red crabs taken from deep 

 water canyons (see Section 2.2: Shell Disease in Red Crabs). We 

 are not aware of any other attempts to identify microorganisms 

 from other New York Bight crustacean species. This question 

 needs to be addressed, and is included in our recommendations for 

 further research (Section 6) . 



° What are the effects of temperature and other 

 variables on molting and shell disease ? 



The effects of temperature and other variables on 

 chitinoclastic microorganisms, or the size and frequency of shell 

 disease lesions, have not been determined. However, temperature 

 and other environmental factors are related to molting activity 

 and it is during intermolt that the prevalence of shell disease 

 appears to be highest (see Section 2.3). 



° What is the effect of molting on shell disease ? 



Successful molting results in the shedding of 

 gross (visible) signs of shell disease with the discarded old 

 shell. Trawl surveys during molting seasons usually provide data 

 indicating the lowest incidences of shell disease at that time. 

 However, severe shell disease, associated with adhesions of the 

 underlying tissues, may interfere with molting and the successful 

 shedding of the old shell. 



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