Aquatic
and
Environmental Services
The need for the analysis of contaminated sediment sites to assess environmental impacts on human and ecosystem health has prompted Sea Engineering, Inc. to bring together a talented group of engineers and scientists to address these and other aquatic environmental problems. Dave Cacchione, Ph.D., Craig Jones, Ph.D., George Tate, and Ken Israel bring together over 50 years of experience in the monitoring, modeling, and analysis of aquatic environmental issues. The group has the capability to quickly bring to bear state-of-the-art equipment, such as Sedflume and the Sediment Transport Monitoring System (STMS), and techniques to accurately and efficiently analyze contaminated sediment as well as other environmental issues.
Oceanographic, Estuarine and Riverine Monitoring
Custom Instrumentation Configurations (STMS)
Measurement and Analysis of Waves, Tides, and Currents
Water Quality Parameter Monitoring
Flux Monitoring
Determination of Oceanographic Design Criteria
Marine Environmental Assessments
Environmental impact statements and assessments
Sediment Stability Analysis through Sedflume
Time Series Bathymetric Change Analyses
Sand Resource Analysis
Permitting
Environmental monitoring
Dredge
Material Assessments
Marine Infrastructure Risk Assessment and Remediation
Oceanographic and Estuarine Hydrodynamic Baseline Analysis
Hydrodynamic and Sediment Transport Modeling
1, 2, and 3-Dimensional Hydrodynamic/Sediment Transport Modeling of Rivers, Estuaries, and Coastal Ocean
Hydrophobic Organic Contaminant Transport
Evaluation of Coastal Processes
Long Term Erosion/Deposition Rates
Extreme Event Analysis
Hurricane and tsunami inundation
Dilution, mixing and transport
Circulation
Wastewater and thermal plumes
Typical Projects
San Francisco Airport Expansion Project (2000)
SEI scientific and engineering staff were key team members with URS Corporation (URSC) in the preparation of an Environmental Impact Report/Environmental Impact Statement (EIR/EIS) for the San Francisco Airport Expansion Project. SEI engineering and scientific staff have designed and deployed suites of Sediment Transport Monitoring Systems (STMS) to collect seasonal current, wave, and suspended sediment concentration measurements in each of the Bay’s characteristic environments. The project team provided analysis and interpretation of hydrodynamic and sediment dynamics measurements and sediment flux estimates in one of the first comprehensive benchmark studies of the San Francisco Bay shallow estuarine environment.
Hunters Point Naval Shipyard (2001)
Sediment Resuspension: Hunter’s Point Naval Shipyard, San Francisco Bay, California. Teamed with Battelle Laboratories to determine the mobility of bottom sediment in areas of potential chemical contamination in the vicinity of Hunter’s Point Naval Shipyard (HPNS), South San Francisco Bay, CA. The study included the deployment of three specially designed Sediment Transport Monitoring Systems (STMS) which were deployed for one month in the Winter and one month in the Summer. The data was used to perform sediment flux analysis at various points surrounding HPNS. These data were used in conjunction with a 2-dimensional wave and current model to determine the potential for sediment resuspension in the region.
Sediment Mobility – Gas House Cove (2001)
Assessment of Sediment Mobility, Gas House Cove, San Francisco. As part of the As-Needed Sediment Sampling, Characterization and Disposal Consultation contract with the City of San Francisco provided a baseline assessment of bottom sediment mobility in the vicinity of Gas House Cove, San Francisco. This work determined the likelihood for resuspension of bottom sediments in this area by using existing sediment, hydrodynamic, and other geological data.
Fort Armstrong Channel Dredging Turbidity Studies, Honolulu Harbor (2000)
A four-lane tunnel is planned to pass under the Fort Armstrong Channel of
Honolulu Harbor to connect Sand Island with Kaka`ako.
This tunnel would require digging a trench across the channel, and
following emplacement of the tunnel, backfilling the trench.
Sea Engineering was responsible for assessing
possible dredging impacts.
This involved completion of a comprehensive current measurement program
in the project vicinity, and development of a numerical model to predict
turbidity transport.
Three current meters were deployed in the entrance channel, the reef flat
and offshore for a four-month period from August through December 1999.
The numerical model used the actual current data records from each area
to simulate dredging turbidity transport into the coastal environment and to
calculate plume visitation frequency throughout the area. Click here
to see one of the turbidity models. Client:
Parsons Brinckerhoff Quade and Douglas, Inc.
Sand Resource Assessment in San Francisco Bay (2000)
Assessed the sand resources in Northern and Central San Francisco Bay to evaluate Hanson and RMC leased sand borrow regions to determine their viability as a renewable sand resource. This work was accomplished using available hydrodynamic, geophysical, sediment, and geological data as well as digital terrain modeling tools and multibeam bathymetric surveys.
Sediment Flux in Wetlands Channels, Sonoma Baylands (1997)
Deployed instrumentation to obtain time-series data on wind, flow, and suspended sediment within a shallow main channel to the Sonoma Baylands Wetlands Restoration region in San Francisco Bay. Analyzed these data to investigate sediment flux into the restored wetland. The effects of changes in wind speed and direction in altering the tidally-driven sediment movement were determined.
Fort
Kamehameha WWTP Ocean Outfall Improvements, Pearl Harbor, Hawai`i (1998)
Sea Engineering, Inc., as sub-consultant to SSFM Engineers, was responsible for conducting the marine environmental studies and the ocean engineering design analysis for a proposed extension of the Fort Kamehameha Wastewater Treatment Plant ocean outfall at Pearl Harbor. Project tasks included compilation and analyses of all existing oceanographic and water quality data in the project vicinity; field measurement of oceanic currents and circulation over a 12-month period using in-situ recording current meters and current drogues; field measurement of water temperature, salinity, and density over a 12-month period; receiving water quality sampling; a detailed bathymetric survey of the project area; underwater reconnaissance to select possible outfall routes; sediment sampling and analysis; evaluation of alternative outfall discharge depths, locations, and diffuser configurations using computer modeling of near and far field dilution; analysis of design waves and wave forces; and evaluation of alternative outfall pipe materials, construction techniques, and anchoring/protection requirements.
Client: Department of the Navy, Pacific Division, Naval Facilities Engineering Command, Pearl Harbor
Ke`ehi Lagoon Hazardous Waste Search and Recovery, O`ahu, Hawai`i (1994)
SEI, as sub-consultant to CET Environmental Services, Inc. of Seattle was responsible for the search and recovery of toxic containers dumped into Ke`ehi Lagoon, in a criminal pollution case that was called one of the state's worst environmental emergencies. Initial recovery of some containers by SEI for the state of Hawaii led to the EPA-funded operation to locate and recover all the containers, and to an FBI investigation to find the responsible parties. In response to the EPA, SEI utilized differential GPS, a high resolution sub-bottom profiler, a digital side scan sonar, and an ROV mounted with scanning sonar and real-time vessel tracking to locate and record the positions of the containers. SEI then recovered the containers using in-house divers and boat operators licensed in hazardous waste operations. Client: U.S. Environmental Protection Agency
Assessment of Potential Areas of UXO Transport in Andrew Bay (2002)
The project assessed areas of potential unexploded ordinance (UXO) transport in the offshore vicinity of Andrew Bay on Adak Island in the Aleutian Island chain of Alaska The objective of the mobility analysis was to determine when and where the types of UXO typically found at Andrew Bay would most likely mobilize and in which direction they were likely to move. The initial phase of the study involved the collection of historical data on UXO deposited and subsequently collected on the beach in the area. Also, available data on the physical characteristics (bathymetry, sediment types, etc.) and environmental conditions (waves, currents, tides, and meteorology) of Andrew Bay and the surrounding area was collected. An analysis was conducted on the dominant physical processes in the area for use in the UXO transport analysis. The next phase of the study entailed the determination of transport characteristics of the UXO and sediments in the area. A numerical model of wave propagation in the vicinity in Andrew Bay was also developed to calculate areas of potential UXO transport under various environmental conditions. The final phase of the study was the development of a risk assessment for UXO mobility. The assessment focused on the probability of UXO movement under average and extreme environmental conditions at Andrew Bay.
Lower Fox River Sediment and PCB Transport Modeling (1999)
Developed state-of-the-art sediment transport model to accommodate sediment erosion date obtained via Sedflume under funding by the EPA and U.S. Army Corps of Engineers. The model was utilized to conduct a detailed sediment transport model of the Lower Fox River in Wisconsin. This model is being used to develop a detailed description of PCB transport in the Lower Fox River basin to determine long term fluxes of PCB’s out of the Fox River into Green Bay.
Kauai Hurricane Vulnerability Study (1999)
Hurricanes are infrequent events in Hawaii, however in 1982 and again in 1992, the island of Kauai was directly in the path of a hurricane passing the Hawaiian Islands. Storm wave damage to coastal communities was extensive, and posed a significant threat to public safety. In order to improve coastal storm wave hazard preparedness, FEMA, through the State Civil Defense Office and the US Army Corps of Engineers, has funded studies of potential coastal inundation by hurricane storm waves. SEI has been contracted to perform these studies for the islands of Oahu and Kauai. The analysis uses numerical computer models developed by SEI, which are based on standard coastal engineering methodology. The work consists of developing deepwater wind and wave fields based on scenario hurricane parameters for Hawaii, transforming the hurricane generated waves to the shoreline, calculating the components of nearshore still water level rise, and determining breaker height, wave runup and inundation along representative shoreline profiles. It is interesting to note that for Pacific islands, which are surrounded by deep water extending close to shore, the largest component of the nearshore still water level rise results from wave setup inside the initial breaker zone, rather than from storm surge (wind stress and atmospheric pressure drop) as is the case on the continental US. The final products of the work are maps of estimated coastal inundation for use by State Civil Defense in their hurricane evacuation planning.
Client: State of Hawaii, Department of Defense; U.S. Army Corps of Engineers, Pacific Ocean Division; and Federal Emergency Management Agency, Region IX
Voyager Submarines Hawaii Artificial Reef Installation (1999)
Voyager Submarines recently sank a ship in 100 feet of water to serve as an artificial reef at their dive site approximately 3/4 mile offshore of Ala Moana Beach Park. Sea Engineering was responsible for preparing the Environmental Assessment, Environmental Impact Statement Preparation Notice, and Draft and Final EIS for the project. SEI also prepared all required permits for the project, including the CDUA, Department of the Army, the CZM Consistency Determination and the DOH 401 Water Quality Certification.
Client: Voyager Submarine Hawaii
Kalamazoo River Sedflume Survey (2000)
Conducted a detailed sediment property survey on the Kalamazoo River for industry client using Sedflume. The study determined erosion rates with depth and variable shear stress at 30 locations in the river. The study also provided bulk densities, critical shear stresses, and particle sizes for the locations. The data was collected for use in the assessment of contaminant transport in the river.
Characterization Study of Delaware River Detritus
Consulting services to analyze and measure detritus loading in the vicinity of the Salem and Hope Creek Generating Stations. The interest in developing a greater understanding of the detritus loading was driven primarily by the need to mitigate periodic heavy detritus loading events that challenge plant operations. Phase 1 was a strategic detritus sampling program in Spring 2000 using two measurement technologies: mechanical sampling and acoustic equipment. The Spring Field Program was completed primarily aboard a survey vessel in the River. The purpose of the Field Program was to collect baseline data, and to test/calibrate the acoustic equipment in preparation for the Phase 2 Continuous Monitoring Program.
Sedflume: A device for the measurement of parameters affecting sediment transport
In the accurate prediction and modeling of sediment transport, one of the most significant processes to understand and quantify is the sediment erosion rate. These rates can change by orders of magnitude, not only as a function of the applied shear stress due to waves and currents but also as a function of horizontal location and depth in the sediment. Because of this, these rates have a major and highly variable effect on transport. In order to quantify these rates and understand the processes on which they depend, Sedflume has been used to measure erosion rates in the field and in the laboratory. In order to apply this information, a numerical model of sediment transport has also been developed which incorporates the use of Sedflume data. In addition, the model includes multiple size classes, a unified treatment of suspended load and bedload, and bed armoring. Applications of this model to sediment erosion, transport, and bed armoring in river systems have shown excellent agreement between calculations and observations. By means of this model and accurate measurements of erosion rates by means of Sedflume, realistic predictions of sediment and subsequent sediment bound contaminant transport can now be made with a minimal amount of calibration or fine-tuning of the model. Sedflume has been used extensively in the field and laboratory for the past 7 years to quantify sediment erosion rates as a function of depth into the sediments, shear stress, bulk density, and sediment composition in both the field and laboratory. Please go to our Publications page for additional information on "Sediment Erosion Rates".
