REPORT DOCUMENTATION PAGE 



form approved 



0MB No. 0704-0188 



Public reporting concern for the collection of information is estimated to average 1 hour per response including the time for reviewing instructions, 

 searching existing data sources, gathering and measuring the data needed and correcting and reviewing the collection of information. Send comments 

 regarding this burden estimate or any other aspect of this collection of information including suggestions for reducing this burden to Washington 

 Headquarters Services, Directorate for information Observations and Records, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302 

 and to the Office of Management and Support, Paperwork Reduction Project (0704-0188), Washington, D.C. 20503. 



1. AGENCY USE ONLY (LEAVE BLANK) 



2. REPORT DATE 



NOVEMBER 1997 



REPORT TYPE AND DATES COVERED 



HNAL REPORT 



4. TITLE AND SUBTITLE 



MONITORING CRUISE AT THE CENTRAL LONG ISLAND DISPOSAL SITE , JULY 1994 



6. AUTHOR(S) 



JOHN T. MORRIS and GREGORY J. TUFTS 



5. FUNDING NUMBERS 



7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 



Science Applications International Corporation 

 221 Thrid Street 

 Newport, RI 02840 



8. PERFORMIGORGANIZATION 

 REPORT NUMBER 



SAIC-327 



9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 



US Army Corps of Engineers-New England Division 

 424 Trapelo Road 

 Waltham, MA 02254-9149 



10. SPONSORING/MONITORING 

 AGENCY REPORT NUMBER 



DAMOS Contribution No. 1 17 



11. SUPPLEMENTARY NOTES 



Available from DAMOS Program Manager, Regulatory Division 

 USAGE-NED, 424 Trapelo Road, Waltham, MA 02254-9149 



12a. DISTRIBUTION/A VAILABILITY STATEMENT 



Approved for public release; distribution unlimited 



12b. DISTRIBUTION CODE 



13. ABSTRACT 



Science Applications International Corporation (SAIC) conducted a monitoring survey at the Central Long Island Sound Disposal Site (CUS) from 10 to 18 July 1994 as 

 part of the Disposal Area Monitoring System (DAMOS) Program. The July 1994 field operations were concentrated over the New Haven 1993 (NHAV 93) and Mill-Quinnipiac 

 River (MQR) disposal mounds and consisted of precision bathymetric, subbottom, surface sediment characterization, and Remote Ecological Monitoring of the Seafloor (REMOTS*) 

 sediment-profile surveys, as well as grab sampling and geotechnical coring. These surveying techniques were used to monitor the stability, cap thickness, and benthic recolonization 

 of the NHAV 93 and MQR mounds. 



In September 1993, two disposal buoys were deployed at CUS. The NHAV buoy was in the center of a ring of disposal mounds as part of a large scale confined aquatic 

 disposal (CAD) project. The CDA buoy was deployed over the previously capped MQR mound as part of a de facto capping and cap augmentation project. Approximately 65,(XX) 

 m' of sediment was deposited at the CDA buoy, adding to the existing layers of dredged material that compose the MQR mound. 



During the 1993/94 New Haven Capping Project, the NHAV 93 mound received approximately 590,(XX) m^ of unacceptably contaminated dredged material (UDM), 

 followed by 569,000 m' of CDM. The ring of mounds gready reduced the lateral spread of die UDM mound apron, facilitating die efficient capping operations and yielding a flat, 

 stable CAD mound. The latest field effort, four mondis after the completion of capping operations, found no major topographic changes in the NHAV 93 mound in comparison to 

 the postcap bathymetric survey of March 1994. The MQR mound height increased 1.5 m, creating a new apex, widi no increase in overall diameter relative to the bathymed-ic 

 survey of December 1991. 



The cap diickness over the NHAV 93 mound was found to meet die minimum cap thickness requirements of die project, 0.5 m. A full specdiim subbottom profile 

 survey (X-Star), in conjunction widi precision badiymetric and geotechnical core data, detected an average of 0.75 m of cap material along the margins of die UDM deposit to 1 .25 

 m at its center. Surface layer grain sizes were assessed widi die use of SAIC's Sediment Acoustic Characterization System (SACS) as well as REMOTS* sediment-profile 

 photography and bottom grab samples. The surface layers of cap material over die NHAV 93 mound were comprised mainly of silt and clay. The MQR mound exhibited a 

 heterogeneous mixmre of grain sizes ranging from silt and clay at die margins of die mound to pebble and cobble size grains at die center of die supplemental CDM deposit. 



Bendiic recolonization of die project mounds was also determined from die REMOTS* photographs. The MQR and die majority of NHAV 93 project mounds met or 

 exceeded die predicted recolonization rates from die DAMOS tiered monitoring and management protocol. However, diree stations on die NHAV 93 mound were found to be areas 

 of concern. Patchy Stage 1 communities and shallow redox potential discontinuity (RPD) depdis were apparent in REMOTS* photographs collected at Stations 200N, CTR, and 

 400S 



In September 1994 additional sediment samples were collected to coaiuct Ampelisca bioassay testing and determine whedier furdier action by NED was required (i.e., 

 cap supplementation). The results of bioassay testing indicated no significant difference in comparison to reference area sediments. Therefore no immediate action was required, 

 but as pan of die DAMOS tiered monitoring protocol, RPD depdis and successional stage stams at Stations 200N, CTR, 400S continued to be closely monitored for changes in die 

 bendiic community. 



Sediment samples were obtained for chemical analysis at die NHAV 93 and MQR mounds, as well as die diree CUS- reference areas. The results of die chemical 

 analyses indicate diat die sediments obtained from die surface of bodi disposal mounds were, in general, similar to die samples collected widiin die CUS reference areas. The PAH 

 concentrations of die NHAV 93 and MQR mound sediments were found to be lower dian die average values for several National Status and Trends (NS&T) stations widiin die 

 central Long Island Sound region. The results of diis sampling and chemical analysis verify die placement of suitable capping materials over bodi mounds. 



14. SUBJECT TERMS 



Central Long Island Sound Disposal Site (CLIS), Mill-Quinnipiac River (MQR), Confined Aquatic 

 Disposal (CAD), New Haven Capping Project 



17. SECURITY CLASSIFICATION OF 

 REPORT Unclassified 



18. SECURITY CLASSIFICATION 

 OF Tins PAGE 



15. NUMBER OF PAGE 1 46 



16. PRICE CODE 



19. SECURITY CLASSIFICATION 

 OF ABSTRACT 



20. LIMITATION OF 

 ABSTRACT 



