Sediments 



Heavy metal data from the Brenton Reef area are presented in Table E-2 . 

 The Brenton Reef samples are all relatively clean, although those taken from 

 the disposal site have higher concentrations than the reference site. When 

 the two sample sites are considered in relation to the whole region they have 

 concentrations so low that they were used, along with Cornfield Shoals and New 

 London, as the basis for deteriming background levels. With the sand layer as 

 a cover over the spoils it is apparent that \jery little heavy metal enriched 

 spoil material is available to the water column over much of the Brenton Reef 

 site. 



Benthic Biochemistry 



Samples of Myti 1 us edulis for the Brenton Reef site were obtained from a 

 reference location known as the Newport Outer Bridge on the south coast of 

 Aquidneck Island approximately two miles north of the disposal area. Data from 

 the reference and disposal sites presented in Table E-3 and Figure E-4 reveal 

 three patterns of heavy metal -mussel interaction. The ratios of Cd and Hg , 

 being within the prescribed 95% confidence limits, show the least change. A 

 distinct increase of the concentraion of Fe is noted in the July 1978 sample 

 obtained from Brenton Reef, while samples of the same period from Newport Outer 

 Bridge and Brenton Reef show concomitant increases in the concentraion of Zn . 

 The third pattern of heavy metal behaviour is characterized by a significant 

 decrease in the concentration of Cu , Fe and Pb from the reference area. When 

 one considers the July 1978 sample from the reference and disposal areas as a 

 set, the concentration of Cu , Fe, Hg and Pb of the former is consistently lower 

 than that of the latter. 



