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Dredging Representative Areas of Experience: 
Summaries of CSA International's Representative Dredging Projects Ocean Dredged Material Disposal Site (ODMDS) Monitoring Off Tampa, Florida CSA monitored the ODMDS offshore Tampa Harbor, Florida during a four-year period for the U.S. Environmental Protection Agency. The project included quarterly measurements of current speed and direction, the collection of soft bottom infaunal and live bottom (hard bottom) samples, the collection of repetitive quantitative transect photographs, and the collection of surficial sediment and sediment trap samples for phosphate, strontium, grain size, and total organic carbon analyses. All samples were collected by divers. The data and samples were analyzed to determine the fate of the dredged material dumped at the site and the effect on biota within the site. Environmental Impacts Statements (EISs) for Ocean Dredged Material Disposal Sites (ODMDSs) Environmental CSA International prepared extensive information for ODMDS EISs according to the National Environmental Policy Act (NEPA) and the Council on Environmental Quality (CEQ) regulations on implementing NEPA procedures. CSA prepared two EISs for the U.S. Army Corps of Engineers, Jacksonville District associated with the designation of ODMDSs offshore Fernandina and Canaveral, Florida. CSA performed a literature and data search and collected information on general physical, chemical, and biological conditions of the Atlantic shore of central and northeastern Florida and southeastern Georgia. Sampling stations were selected in the Fernandina and Canaveral project areas based on prevailing currents. Field surveys were conducted to characterize the water column and benthic characteristics of each area. Data were collected for bathymetry, salinity, temperature, dissolved oxygen, turbidity, total suspended solids, granulometry, sediment trace metals, PCBs and chlorinated pesticides, high molecular weight hydrocarbons, oil and grease, total organic carbon, macroinfauna, meiofauna, and macroepifauna. Results of the field surveys were incorporated into the two EISs. CSA also has conducted four ODMDS EIS projects for the U.S. Environmental Protection Agency. CSA reviewed the "Draft EIS for the Atchafalaya River Bar Channel ODMDS Designation and provided bibliographic references to be used in updating the Draft EIS. CSA also prepared the Supplemental Draft EIS for the designation of the Atchafalaya River Bar Channel ODMDS. CSA reviewed the Draft EIS for the Southwest Pass ODMDS and updated the Affected Environment section based on recent literature. CSA reviewed the Draft EIS for the Calcasieu River and Pass ODMDS designation and updated the Affected Environment section with information from recent literature.
Transplantion of Corals Associated with Dredging the Habor Channel at Fort Pierce, Florida CSA International conducted diver reconnaissance surveys of scleractinian coral colonies on rock habitat within the dredging impact area along the north edge of the Fort Pierce Harbor navigational channel. The surveys for the U.S. Army Corps of Engineers, Jacksonville District in 1994 provided approximate number and location of coral colonies within the survey area. Wormrock also was recorded in the survey area. During 1995, CSA conducted surveys to relocate hard coral colonies (Oculina sp.) along the north slope of the channel and to transplant these corals to a suitable offshore location. Coral colonies were removed from the channel and successfully reattached to a shallow reef adjacent to the inlet. CSA collected and analyzed video and still photographs to document the operations and monitor the success of the coral reattachment into 1996. Review of Sediment Contamination in Texas and Louisiana Dredged Channels CSA International conducted a review of literature and data availability on sediment contamination (dioxins, furan complexes, PCBs, and hexachlorobenzenes) in dredged channels of Texas (Freeport Harbor, Sabine-Neches Ship Channel, Matagorda Ship Channel, and Houston Ship Channel/Galveston Harbor and Channel) and Louisiana (Calcasieu River and Pass, Mississippi River Gulf Outlet, and Southwest Pass). A Work/Quality Assurance Project Plan was developed and approved by the U.S. Environmental Protection Agency, Oceans and Coastal Protection Division prior to the actual literature review. Appropriate data sources were identified and acquired. Literature and data were summarized and synthesized in a final report that was used as the basis for developing a sampling/survey plan to be utilized in Phase II of the project. Thin Layer Dredged Material Disposal Off Mississippi CSA Internatioanl assisted in performing a water quality monitoring program for turbidity and nutrients for the U.S. Army Corps of Engineers (USACE), Waterways Experiment Station. The purpose was to determine impacts associated with the National Demonstration Project for Thin Layer Dredged Material Disposal conducted by the USACE, Mobile District along the entrance channel through Mississippi Sound into the port at Gulfport, Mississippi. CSA provided field sampling planning, logistics, personnel, and equipment to conduct a series of 24-h monitorings coordinated with pre-, during-, and post-dredging surveys according to schedules that examined the tidal cycle effects of dilution and dispersion of turbidity plumes. Sediment Toxicity in San Francisco Bay CSA International provided field and analytical support to the U.S. Department of Commerce, National Oceanic and Atmospheric Administration for a study of sediment toxicity in San Francisco Bay. CSA sampled soft bottom sediments at 45 sites located throughout San Francisco Bay. At each site, three replicate sediment samples were collected with a Teflon-coated Gray-O'Hara box core. Sediment samples were processed in the field using clean techniques. Subsequently, the toxicity of these sediment samples was determined by five different test procedures, including bivalve larval bioassay, bacterial bioluminescence, bacterial enzyme synthesis, bacterial mutagenicity, and subcellular mutagenic response methodologies. A determination of the geographic extent of the toxicities associated with San Francisco Bay sediments, coupled with a comparison of the performance of these differing test methods, also were completed as part of a comprehensive data report. Clearance Survey for the Ocean Dredged Material Disposal Site (ODMDS) Offshore Harbor, Florida CSA International provided technical support to the U.S. Environmental Protection Agency (EPA, Region IV) and conducted a clearance survey to locate a new ODMDS offshore Charlotte Harbor. The survey was conducted from EPA's research vessel, the OSV ANDERSON. A side-scan sonar and underwater color television/still camera was towed simultaneously to locate a suitable two mile by two mile disposal site within an economically feasible range of Charlotte Harbor. The final site was mapped with overlapping side-scan sonar coverage, continuous television along 200-meter spaced transects, and still photographs taken at 300-meter intervals. Criteria were developed and a final report was produced that satisfied the EPA, U.S. Army Corps of Engineers, and State of Florida. Archeological Investigation for Dredging Associated with the Balimore Harbor and Anchorages Project CSA International conducted a submarine archeological investigation for the Baltimore Harbor and Anchorages Project using a CHIRP subbottom profiler interfaced with CSA's Differential Global Positioning System (DGPS) navigation system. The purpose of the survey was to identify magnetic anomalies found during a previous magnetometer survey of an area to be dredged. The magnetic anomalies might have represented a shipwreck buried under sediments that were possibly contaminated. Conventional subbottom systems used previously in the survey area were prevented from collecting data by biogenic gas deposits in the sediments. The CHIRP system successfully produced high quality subbottom records showing the targets responsible for the magnetic anomalies. All anomalies located in the survey area were identified as modern debris and not as cultural resources. The subbottom survey prevented the safety risk associated with diver excavation and identification under these conditions. This project was conducted for the U.S. Army Corps of Engineers, Baltimore District.
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CSA International
has a long history of collecting sediment and
water quality data for dredging and disposal projects.
Samples and measurements have been collected for
the U.S. Army Corps of Engineers at more than
25 locations throughout Florida, Georgia, and
Puerto Rico. Both dredging and disposal sites
have been studied using CSA's portable vibracoring
system mounted on CSA's 25-ft trailerable outboard-powered
pontoon barge. The vessel supports a 15-ft bow-mounted
A-Frame and a wide variety of grabs and gravity
or diver cores. Typically sediment samples were
homogenized after collection to provide representative
material for bioassays and a full suite of chemical
analyses including pesticides, metals, and hydrocarbons.