Bay Bridge Oil Spill/Eelgrass Bed Protection
Oakland, California
Client: MCM Construction
DMS was involved in the massive oil spill cleanup effort that took place in San Francisco Bay, in November of 2007. Currently maintaining a turbidity curtain around the environmentally sensitive area (ESA) of eelgrass beds during the Oakland Touchdown Project, DMS was called in to place 20,000 feet oil boom around the ESA within 72 hours of the spill occurring using the RV Lakota. As DMS install the oil boom additional flat bottom vessels trawled inside the area cleaning up oil.
Castro Cove Sediment Remediation Project
Richmond, California
Client: Arcadis-BBL/Chevron Refinery
The Castro Cove Sediment Remediation Project involved dredging approximately 80,000 cyd of impacted marine sediments in San Pablo Bay and placing them in an existing oxidation pond on the Chevron Refinery in Richmond CA. The Area of Concern(AOC) was isolated in Castro Cove using temporary sheet piling enclosure to minimize impact to the bay. DMS hydraulically removed sediments from the AOC via a 14 inch HDPE SR-17 pipe line constructed by DMS to a depth of 2.5 feet below existing mud surface. The water was separated from the sediment with two settling ponds located on the refinery property, and returned to the AOC with a 12 inch HDPE SR-17 pipeline also constructed by DMS to keep elevations constant in the AOC. To transport water back to the AOC, five diesel powered pumps (three 6 inch and two 8 inch pumps) and three flashboard weirs were used to control water depths in the settling ponds. For initial water levels in the AOC, a 12-inch diesel pump was set up with automatic control float switches which tr
ansported water through a specially designed fish screen to keep entrance velocities below .2 ft /section so as not to entrain the Delta Smelt (Endangered species). The intake screen was constructed with an automatic self cleaning screen to ensure entrance velocities did not climb over the course of the project. DMS also managed the decant water through a set of remote data collection platforms and data sondes; multi-parameter instruments that collect water quality data automatically and transmit the data via a wireless connect to a base station located on site. The platforms allowed DMS to monitor water quality as it circulated through the site, and did not cause variation to water of the bay when discharged back into the cove. The sediment placed onsite at the Chevron refinery oxidation ponds was treated naturally with elevated levels of oxygen and bacteria pumped through the material to break down potentially hazardous constituents.
Hamilton Wetland Restoration Project
Bel Marin Keys, California
Client: Manson/Dutra Joint Venture
The Hamilton Wetland Restoration Project involves converting 630 acres of the former Hamilton Army Airfield using dredged material from the Oakland Harbor Deepening Project. DMS assisted in the formulation and initiation of the 
Operations Plan for the site, and continues to perform the water quality monitoring duties for theOff-loader in San Pablo Bay, and onsite at the Hamilton Airfield.. DMS installed a remote monitoring platform in a settling basin onsite, and in San Pablo Bay on the Manson Superbooster to monitor water quality for the entire cycle through the Hamilton Airfield.. The quality of water as it percolates through the site has been closely monitored and advised by DMS to maintain compliance regulations with the San Francisco Regional Water Quality Control Board, and to provide the most efficient program for maintaining the quality of water onsite. This project is expected to be mostly complete by June 2009, , forming both seasonal and tidal wetlands from beneficial dredge refuse. This project was recently the cover story for World Dredging Magazine(Volume 44, Nos. ½) as an innovative effort for management of such a large amount of sediment material.
Lower Snake and Clearwater Rivers
Southeast Washington State
Client: Manson Construction Company
The USACE instituted a maintenance dredging program that involved 80+ miles of the Lower Snake river during the winter months of 2005-2006. As part of the successful team, DMS built eight independently powered water quality monitoring stations, and developed remote data gathering capabilities to monitor water quality of the Lower Snake river during all dredging and disposal operations. DMS constructed a monitoring network at the disposal and dredge sites with specially designed instrumentation built by Eureka Environmental and Eyasco, Inc. Each network was designed with four monitoring stations containing an independent solar energy and backup battery source, a data telemetry system to transmit data to remote locations, and two Eureka Environmental Manta multi-probe sondes per platform. The Manta units were designed to monitor seven parameters (temperature, dissolved oxygen, 
specific conductivity, pH, turbidity and ammonia) as specified by the USACE, States of Washington and Idaho.
The Manta units were continually exposed to freezing wind and rain, pulled through the water with the movement of each station, and exposed during daily field calibration events. In order to assure accuracy of the program, DMS provided calibrations beyond what was required by the contract, checking instruments twice daily for any indications of instrument failure. The Manta units continued to r
ecord accurate data throughout the entire project.
At the conclusion of the Lower Snake River Dredging project, over 2 million data points had been collected by the Mantas. The agencies involved were successfully able to determine water quality trends along both the Snake and Clearwater Rivers for future projects and isolate problematic factors that would need further in-depth analysis. The Mantas were remarkable in their versatility during adverse conditions, and provided excellent data for use in analysis. Dredge spoils were beneficially reused for the construction of a shallow water habitat for salmonids.
Montezuma 
Wetlands Restoration
Solano County, California
Client: Montezuma, LLC
The Montezuma Wetlands Restoration Project is a combined effort by Levine-Fricke Restoration Corp., the U.S. Army Corps of Engineers (USACE), San Francisco Estuary Institute (SFEI), and the Port of Oakland to return local farmland to its original wetland state using an upland ecosystem format of high and low marsh created with sediment material from the Oakland Bay dredging project. 
The Montezuma Wetlands encompass approximately 1800 acres in Solano County near the Montezuma Slough and Grizzly Island Wildlife Area. This restoration project will provide habitat for both locally endangered species of plants and animals.
DMS has been proud to be a part of this effort since 2001. As part of the restoration team, we have performed the following services:
Construction management services: DMS oversaw up to nine firms at a time performing work activities related to the wetland restoration. All communications to the client and involved agencies were routed through DMS.
- Site operations including:
• Water management including creation of a hydraulic model to establish a water balance of the site
• Sediment compliance monitoring
• Elevation monitoring of the mud surface using differential ground-positioning sonar (DGPS) survey techniques to evaluate consolidation rates
• Bathymetric surveys of ponds and channels
- Construction services including:
• Conveyance piping and control structure installation
• Hydraulic and mechanical dredging of channels to enhance site water management
• Vernal pool construction
- Water quality monitoring during and after sediment placement
- Biological monitoring of the species, density and activities of shorebirds, the western pond turtle, and the endangered salt marsh harvest mouse..
Transbay Power Cable Survey & Vibracore
San Francisco, San Pablo, & Suisun Bays
Client: Alpine Ocean Seismic Survey
DMS provided the marine vessels and support platforms necessary for all equipment, collection devices, and diver to travel from Oakland Harbor to Pittsburg in the Suisun Bay during the winter months of 2006-2007. Working with the survey crew and dive team to ensure quality assurance and control for all actions conducted, the research vessel, RV Lakota, conducted a survey of the San Francisco Bay using a side swath, transducer and magnetometer for Alpine Ocean to submit for the installation of a dc power cable to run from Pittsburg to South San Francisco on the bottom of the bay.
After the completion of the survey work DMS was responsible for acquiring 150 sediment core sample along the cable route. The RV Lakota was used to take the bulk of the core sample with a penetration depth of 15 feet with a 6 inch head and 4 inch core diameter. The RV Lakota took core in the roughs conditions the bays could trough at her from 20 to 40 knot wind to 7 knot currents. Cores were taken in 20 to 200 feet of water depth. In certain locations in which the there was a need for 20 foot Vibracore depths a tug, barge, and crane were used.
Tesoro Refinery Sediment Sampling
Martinez, California
Client: Blasland, Bouck & Lee, Inc
As part of an ongoing remediation program, DMS provided sampling services to address data gaps in order to better quantify exposure risk and aid in differentiation of the potential remediation alternatives. The program included using 2 and 3-inch push cores to collect in excess of 400 sediment samples along established transects while aboard air boats and shallow draft skiffs.
Samples were subjected to a broad spectrum of analyses (VOC, SVOC and CAM metals) and studies (grain size, leachability, stabilization, and hanging bag dewatering test) in order to adequately characterize the sediments in the onsite canals, wetlands and settling ponds. Water quality monitoring was performed in the canals and waterways discharging to the Bay and included: turbidity, dissolved oxygen, ammonia, pH, and specific conductivity.
Vibracore work was performed using a 70-ton truck crane. Sampling personnel used supplied air respiratory protection due to the potential exposure to hydrogen disulfides. DGPS was used to locate all sampling locations across the site so that the owner could archive the data points into their GIS.
Harbor Seal Monitoring
Redwood City, California:
Client: URS
Dixon Marine Services, Inc. assisted and provided the platform for the bathymetric surveying and marine mammal monitoring in the bay/marsh near the train trestle during sounding surveys occurring outside the port of Redwood City.
San Francisco Bay Bathymetric Survey Project
Mouth of San Francisco Bay, California
Client: USGS
Dixon Marine Services, Inc. provided the platform for the USGS to perform several bathymetric surveys outside the mouth of the San Francisco Bay. Using a 50 foot research vessel with a minimal draft, the team was able to navigate into shallow water using precise instrumentation and state of the art equipment to gather the data necessary to complete the survey.
Moss Landing Harbor
Moss Landing, California
Client: Moss Landing Harbor District
In 1997, widespread flooding resulted in huge sediment loads to be deposited in Moss Landing Harbor rendering it difficult to navigate. In coordination with FEMA, the Moss Landing Harbor District (MLHD) required that approximately 250,000 cubic yards of pesticide-impacted dredge spoils to be treated and stabilized in accordance with Dredge Materials Management Office requirements.
Since 1998, MLHD has looked to DMS to provide upland management of the chemically challenged dredge spoils. Approximately 250,000 cubic yards of pesticide-impacted sediments were treated and stabilized for beneficial re-use within the harbor and at the local landfill. Dredge spoils were treated with calcium and magnesium oxide until engineering quality was reached, and the material could be used as engineered fill. DMS used this fill to repair and grade many of the parking lots within the harbor as well as to repair the access road to the local landfill.
Dredge spoils were conveyed to the treatment pond via a 9000-foot HDPE pipeline constructed by DMS. The pipe was installed underwater to prevent disruption of local navigation. The pond processes 3500 cubic yards of spoils per week. Decant water from the site was monitored hourly through a remote monitoring buoy and was compared to background water quality that was also monitored hourly. Additionally a rigorous analytical program was implanted to meet the requirements established by the regulatory agency.
Antioch and Pittsburg Power Plants
Contra Costa County, California
Client: Mirant
DMS was asked to assist Mirant in complying with permit requirements established by NOAA and California Department of Fish & Game for their Antioch and Pittsburg power plants in Contra Costa County. Because they had exceeded the velocity rates stipulated in the permits for their cooling water intakes, velocity studies were performed the 400-foot intakes pipes at each plant. The results of the velocity studies indicated that sediments that had deposited on the inside of these pipes would have to be removed.
As a result, DMS performed a diver-assisted dredging operation to reduce the amount of sediment and lower the velocity at which these pipes removed water from the San Joaquin River (Antioch plant) and Suisun Bay (Pittsburg plant). Divers manually directed the intake of a small suction dredge within the intake structure. Sediments were decanted in 20,000-gallon separation tanks that separated the solids for the liquids. Sediments were collected in a geotube and decant water was treated with a series of sand filters and discharged to the facilities water treatment plant.
Scottsdale Pond
Novato, California
Client: The City of Novato
The City of Novato wished to take a degraded pond and provide recreational public access, improve water quality, create and enhance wildlife habitat, and provide screening from an adjacent highway. As part of the engineering team whose scope included deepening the pond, stabilizing the shorelines, creating a wildlife island, and installing water circulation pumps and aerators, DMS was responsible for dewatering the site, performing wildlife salvage and habitat relocation. DMS created a temporary holding pond into which hundreds of fish were collected, placed, fed, and relocated. DMS also relocated several nesting birds in the area to more suitable areas not immediated impacted during construction events.
Napa River Flood Control Project
Napa County, California
Clients: Mass Ex Corporation, Envirocon, R.L. Brosamer
DMS worked on the Napa River for three consecutive construction seasons performing water quality sampling and monitoring for the Flood Control District, and the Regional Water Quality Control Board. Our services have included installing and maintaining approximately 10,000 linear feet of turbidity curtain in accordance with NPDES regulations and collecting in-situ water samples for water quality analysis where work was conducted below the low-water mark. In addition, DMS field staff conducted visual surveys during work activities in order to evaluate potential impacts on wildlife in and around the construction site. Evaluations included occurrence, density and activities of waterfowl, shorebirds and fish.
Fort Bragg Sediment Sampling
Fort Bragg, California
Client: Arcadis-BBL
Recently, the Georgia Pacific Lumber Company put on the market a 400-acre piece of property within the city limits of Fort Bragg, formerly the site of a large mill facility. The mill was shut down in 2002, and the facility takes up almost the entire coastline of Fort Bragg. The public of Fort Bragg has embraced the mill site as the future of Fort Bragg and has proposed many uses for the site: a marine research center, a conference center, a world-class golf course, a smaller mill, or a branch of a college. Before any construction begins, a survey was necessary onsite to determine if there were any remaining hazardous materials in the soil that required remediation. DMS collected several vibracore samples in various locations onsite at the former lumber mill. At least two vibracore samples were collected at each of the seven ponds on site at the former lumber mill, using an airboat for push cores, and a crane for vibracore samples down to 10 feet below the mud line.
Chevron Long Warf Sediment Sampling
Richmond, California
Client: Arcadis-BBL/Chevron Refinery
Periodic dredging is required to keep Chevron Long Warf access for the large oil tankers to offload and fill their holds. Before this dredging process begins it is require to test the sediment before dredging to determine where the dredged spoils can be disposed of. DMS Provided the RV Lakota with her 6 in Vibracore to sample 22 different locations in water depths of 3 to 40 feet. All the cores samples were 4 inch in diameter and penetrated down to 15 feet deep. Each sample location was record using a DGPS system on board.
Richmond Inner Harbor Sediment Sampling
Richmond, California
Client:
Periodic dredging is required in Richmond Inner Harbor to allow deep draft vessels from running aground in the channel. DMS was responsible from taking 17 core samples along the channel to provide information of the sediment contamination and where the sediments will be allowed to be disposed of. DMS used the RV Lakota and here 6 inch Vibracore to perform the work. Each sample location was located using a DGPS System and all samples were 4 inch in diameter and to depths of 15 feet.
