U.S. Army Corps of Engineers, San Francisco District - Pinole Shoal Channel, 2010 Maintenance Dredging - Sediment Sampling, Characterization, Reporting and Consulting Services

Pinole Shoal Federal Channel during favorable sampling conditions of slack tide
Prime Contractor: 
Period of Performance: 
April, 2010 to May, 2010
Project Description: 

As a part of its Operations and Maintenance Dredging Program for 2010, the U.S. Army Corps of Engineers (USACE) developed a sampling and analysis plan to characterize sediments proposed for dredging within the Pinole Shoal Federal Channel. The USACE proposed to conduct currently authorized dredging within specific channel reaches and to conduct advance maintenance dredging in other reaches of the channel in order to maintain the authorized depth for a longer duration. Approximately 11 miles long and 600 feet wide, the Pinole Shoal Federal Channel is a vital deep-draft shipping channel located along southeastern San Pablo Bay that serves commercial vessels en route to ports from Concord to Sacramento. The USACE contracted with ADH to carry out the sampling and analyss plan and evaluate the sediments for multiple disposal/reuse options.

Scope of Services: 

 

Based upon the USACE’s Pinole Shoal Channel 2010 Regular and Advance Maintenance Sampling and Analysis Plan (SAP), ADH developed and managed all technical aspects of this contract. In association with our vessel and vibracoring subcontractors – TEG Oceanographic Services and Monterey Canyon Research Vessels - ADH staff performed all sediment coring and site water sampling from three regular and four advance dredging composite areas and two in-Bay disposal sites. The sediment composite samples were subjected to Tier III Testing - a comprehensive suite of physical, chemical, and biological analyses. Toxicity bioassay testing included benthic sediment, elutriate and water-column analyses.

Physical, chemical and toxicological analytical methods followed procedures specified in the Inland Testing Manual, the Ocean Testing Manual and the Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms. All analytical results were evaluated to determine the channel sediment’s suitability for multiple disposal/placement options including upland placement at the Hamilton Wetland Restoration Project (HWRP), in-Bay disposal at sites SF-09 or SF-10, and ocean disposal. Sediment chemistry and toxicity results were evaluated in relation to criteria established in the U.S. Fish and Wildlife Service’s Biological Opinion (HWRP BO) on placement of dredge materials at the HWRP, as well as to San Francisco Bay Ambient Sediment Concentrations, and historical data from the San Francisco Deep Ocean Disposal Site Reference Area.

 In order to meet the USACE’s tight scheduling requirements, prior to the completion of toxicity and bioaccumulation tests, ADH prepared a preliminary sediment evaluation report on just the physical, chemical and MET metals and toxicity data results. Draft and final sediment evaluation reports were prepared by ADH for the USACE and followed guidelines provided in the SAP and Public Notice 99-4: Sampling and Analysis Plan (Quality Assurance Project Plan) Guidance for Dredging Projects within the San Francisco District.

The project was overseen by the USACE and the final report incorporated comments from the USACE and agencies from the Dredged Material Management Office, including USEPA Region 9, San Francisco Bay RWQCB, and the Bay Conservation and Development Commission.