with the remaining two images showing evidence of Stage I 

 assemblages. In this survey, two images from station CTR exhibited 

 Stage III-I assemblages. Stage III assemblages were predominant 

 throughout much of the mound except for the southern transect. 

 The origin of the relatively low-order successional status of the 

 southern region of the mound is unknown, but it may have been 

 related to the proximity of the adjacent NH-83 and MQR disposal 

 mounds. 



From the 4 4 images taken at Norwalk, 37 of them had an 

 Organism-Sediment Index of +7 or higher (Figure 3-69) . As seen on 

 the frequency distribution histogram, most of the values fell at 

 the +7 and +11 class intervals. In the September 1984 survey, the 

 lowest OSI values were located in the southern transect limb 

 extending from center to 450S (Figure 3-72). This pattern 

 continued, and it may have been related to the influence of the 

 disposal mounds to the south. However, the general recolonization 

 of this mound had progressed markedly since the 1984 survey. 



3.3.6 New Haven '74 (NH-74) 



This mound has been studied on an irregular basis since 

 the original 1972 baseline study; the first REMOTS® survey of this 

 mound was performed in September 1984. This mound was originally 

 created by the disposal of New Haven Harbor channel muds which were 

 capped with clean sand. The 1985 survey was conducted on 14 

 August . 



As in September 1984, the major modal grain-size was >4 

 phi (silt-clay) . Images from station 200N revealed a relatively 

 mud-free sand cap. This cap ranged in thickness from approximately 

 1 to 10 cm as measured from the three station replicates. Station 

 200W also showed a thin layer, to 1.5 cm thick, of very fine sand 

 (4-3 phi) at the sediment surface. This station also had an 

 anomalously thin RPD and low successional status, possibly 

 indicative of a recent erosional event. 



As at the Norwalk mound, 53% of the stations at _NH-74 

 showed patches of reduced sediment at the surface. Again, this was 

 apparently due to large-scale biogenic sediment reworking. 



The overall distribution of boundary roughness values 

 remained unchanged over those measured in September 1984. The 

 major modal value fell within the 0.40 cm class (Figure 3-73). 



The major modal RPD depth for all the stations sampled 

 was at the 4 cm class interval (Figure 3-73), one size-class 

 interval higher than measured in September 1984. However, an 

 examination of only the nine station locations sampled in 1984 

 revealed the same major modal value (4 cm) in 1985. Station 200W, 

 sampled in both surveys, experienced a dramatic change in its 



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