individuals were much less (average 487 vs. 2053) . A number of 

 species also present at other mounds are indicators of high organic 

 content or pollution (Oligochaeta, Mediomastus . Cossura, Polydora ) . 

 Some species may have been absent from FVP Center because of some 

 undetected negative effect. The bivalves Mulinia and Nucula and 

 the polychaetes Paraonis and Melinna were much less abundant at FVP 

 Center than at the reference station. The polychaetes Pherusa and 

 Sigambra were found in both sand at STNH-N and silt/clay at CLIS 

 reference, but not in the mixed sediment at FVP Center. 



Benthic community analyses were conducted at the STNH-N 

 mound because it had a different grain-size than the surrounding 

 bottom. The STNH-N Center fauna was dominated by tube-dwelling 

 polychaetes. These included suspension feeders such as Polydora 

 and Spiophanes . and deposit feeding ampharetids, terebellids, and 

 maldanids. Species which have a strong association with sandy 

 bottoms included the polychaete Spiophanes , the bivalves Tellina 

 and Ensis , and the amphipods Unciola and Leptocheirus . Species not 

 seen in previous studies at the CLIS disposal site included the 

 burrowing mud shrimp Callianassa atlantica and the polychaete 

 Ancistrosyllis qroenlandica . 



The results from the benthic infaunal community analyses 

 confirmed the infaunal successional stage designations made 

 independently during analysis of the REMOTS® photographs. Of the 

 three disposal mounds sampled for detailed infaunal analyses, STNH- 

 N station Center had the greatest infaunal numerical abundance and 

 species richness. All the replicate REMOTS® photographs from STNH- 

 N Center showed a particularly dense Stage III-I assemblage; 

 taxonomic identification confirmed the presence of numerous surface 

 suspension-feeders and grazers ( Polydora . Spiophanes . Tellina , 

 Ensis ) as well as subsurface deposit-feeders (e.g., maldanid 

 polychaetes) . The new CLIS reference station (also given a Stage 

 III-I designation in the REMOTS® analysis) also was dominated by 

 deposit-feeders ( Nucula . Yoldia . Euclymene . Asychis ) with the 

 suspension-feeding mactrid bivalve Mulinia lateralis present in 

 fairly high abundance. Of the three replicate REMOTS® photographs 

 from the FVP Center, two received a Stage I designation and one 

 received a Stage III-I designation, indicating small-scale spatial 

 heterogeneity with infaunal taxa. Results of the infaunal analyses 

 showed the Stage I taxa Mediomastus . Cossura . and oligochaetes as 

 dominants along with the Stage III taxon Nephtys . MQR, the most 

 faunally depauperate mound of all CLIS areas surveyed with REMOTS® 

 also had the lowest abundance and species richness from the grab 

 analyses; all replicate REMOTS® photographs analyzed from the MQR 

 Center showed a Stage I successional assemblage, and the presence 

 of Stage III organisms on the MQR mound was documented for the 

 first time. Results from the benthic infaunal analyses confirmed 

 the presence of Stage I taxa as dominants ( Mediomastus , Melinna ) 

 and also the presence of Stage III taxa ( Nephtys . Euclymene ) . 



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