disposal area than at the reference sites (Mann-Whitney U-test; p 

 = 0.0299) (Figure 3-10). The RPD values in the disposal site have 

 significantly deepened since the July 1986 REMOTS survey 

 (Mann-Whitney U-test; p < 0.001). This suggests enhanced biogenic 

 sediment reworking by the infaunal benthos. 



The mapped distribution of infaunal successional seres 

 at the disposal site (Figure 3-11) shows that only one station, 

 4-200SE, lacks evidence of Stage III infauna. This contrasts with 

 the pattern observed in July 1986 when many stations lacked 

 evidence of deep-dwelling, deposit-feeding taxa. The widespread 

 appearance of Stage III taxa at the disposal site indicates that 

 successful infaunal recolonization of the region is occurring. 

 The disposal activity of the past year does not appear to have 

 markedly affected the rate of this recolonization. In addition, 

 tube-dwelling amphipods were evident at many of the stations in 

 the disposal area (Figure 3-12) . These Stage II seres have been 

 observed in all previous New London REMOTS surveys. Stage III 

 taxa were present at all three reference stations, while Stage II 

 taxa were observed only at NLON-Ref. 



The distribution of Organism-Sediment Indices (OSI) at 

 the disposal site (Figure 3-13) indicates that most stations 

 exhibited relatively high OSI values; this reflects the high-order 

 successional status and relatively deep RPD values present across 

 the site. It is noteworthy that the lowest OSI value occurs well 

 south of the disposal area (station 1000S) . This relatively deep 

 area may be subject to periodic hypoxic conditions which were not 

 occurring at the site. OSI values within the disposal site do not 

 differ significantly from the values at the reference stations 

 (Mann-Whitney U-test; p = 0.0715) (Figure 3-14). OSI values were 

 significantly greater t-han those observed in July 1986 

 (Mann-Whitney U-test; p < 0.001). This increase in OSI values 

 reflects the successful infaunal recolonization which has occurred 

 at the site in the past year. 



3 . 3 Dissolved Oxygen 



Near-bottom dissolved oxygen (DO) concentrations were 

 analyzed at approximately 50% of the REMOTS stations occupied at 

 New London on 27 and 29 July (Figure 3-15) . The sampling on 27 

 July occurred solely at stations in and immediately adjacent to 

 the disposal site; the DO values on this day ranged between 6.57 

 mg/1 to 7.35 mg/1. On 29 July, the reference stations and 

 stations to the extreme south and north of the site were found to 

 have near bottom DO concentrations ranging from 3.58 mg/1 to 7.02 

 mg/1. It is noteworthy that the three reference stations (W-Ref, 

 NE-Ref and NLON-Ref) and 1500NW had the lowest near-bottom DO 

 values (3.58, 4.00, 4.37, 3,61, respectively). 



