these two nutrients varies in the same way, the N:P ratios remain fairly 

 constant, with a few exceptions. Nitrate is usually the limiting nutrient. 



Near the dumping grounds, N:P ratios were considerably lower on the 

 average than elsewhere in the Bight, ranging from to 14.42 for surface 

 waters, and from to 7.70 for bottom waters. The low N:P ratios cannot 

 be attributed to low nitrate concentrations, but to high phosphate con- 

 centrations. In fact SHL found nitrate concentrations of up to 3.25 

 Mg-at/1. Chlorophyll-a ranged from 0.38 to 33.3 ug-at/1. This ranges of 

 nutrient concentration found in the Bight are summarized in Table 5. The 

 effects of nutrients on water and sediment characteristics of the dumping 

 grounds are discussed at another section of this report. 



d. Heavy Metals . Sewage sludges, dredge spoils, and other waste 

 materials dumped in the ocean contain many substances, including heavy 

 metals. Tables 6 and 7 show the major and minor elements found in the 

 sewage sludges destined for the Bight dumping grounds (Gross, 1970). 

 Table 7, shows the concentrations of these elements in sewage sludges as 

 determined by spectrochemical analysis and the origin of some of these 

 waste materials in the New York area. 



Sewage sludges and polluted dredge spoils from other heavily industrial- 

 ized regions also contain certain heavy metals in high concentrations. 

 The concentration ranges of such heavy metals are shown in Table 8 (Train, 

 Cahn, and MacDonald, 1970). Table 9 summarizes relative quantities of 

 certain potentially troublesome elements in wastes originating from the 

 New York Metropolitan Region. These concentrations were determined by 

 the SUNY-SB study (Gross, 1970). Particularly noteworthy are the re- 

 latively high concentrations of lead, chromium, copper, zinc, and silver. 

 The median concentration values of these metals in wastes and sediments 

 from different locations are summarized in Fig. 23. 



Gross (1971) investigated the distribution of samples containing 

 anomalously high total concentrations of heavy metals and compared this 

 distribution to the distribution of carbon-rich deposits on the Continental 

 Shelf of the Bight. Heavy metals were analyzed by emission spectro- 

 scopy. Total lead concentrations in the waste deposits were over 10 

 times higher than the average lead content of marine organisms or shale. 

 The distributions of the heavy metals, copper, chromium, lead, and silver 

 of the sediments of the dumping grounds are shown in Figures 24 through 

 27. Other acid-extractable minor elements in wastes and waste deposits 

 were determined by the SUNY using optical emission spectrochemical 

 analysis. On the average, about 1 percent of the total metal concentra- 

 tion was extractable by hydrochloric acid (HCl) except nickel (about five 

 percent was extracted). A high correlation was found between total and 

 extractable concentrations of copper, chromium, and iron, suggesting 

 that these elements are well dispersed in the samples and generally occur 

 in chemical states little affected by HCl treatment. No apparent corre- 

 lation was determined between acid-extractable and total tin concentra- 

 tions. Correlation between extractable and total lead concentrations 

 was relatively poor. The study concluded that because of the low 



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