HAMILTON ARMY AIRFIELD WETLAND RESTORATION
CONGRESSIONAL DISTRICT: 6th District, Rep. Lynn Woolsey
STUDY DESCRIPTION: The Hamilton Army Airfield project site is a 700-acre parcel of land, including the adjacent 200-acre State Lands Commission (SLC) parcel, consisting of an inactive runway and adjacent taxi areas, and the former antennae field. The site is located on San Pablo Bay, 4 miles east of the city of Novato, in Marin County,
California. The area, currently protected by levees, has subsided below the elevation of surrounding properties, including the tidal wetlands immediately adjacent to San Pablo Bay. Storm water runoff from adjacent properties is collected on the airfield and transferred from the site to San Pablo Bay by a drainage system which includes a pump
station and concrete ditches. In conjunction with the ongoing Base Realignment and Closure (BRAC) cleanup process, the Base Reuse Authority would like to restore the area to a tidal wetland. This wetlands restoration project would advance the beneficial reuse of dredged material from San Francisco Bay as part of the Long Term Management Strategy (LTMS).
FISCAL YEAR 03 BUDGET: $3,900,000
POSSIBLE SOLUTIONS: Wetlands would be created with the use of dredged material from San Francisco Bay navigation projects, including the Oakland 50’ deepening project.
PRESENT STATUS: The Final Feasibility Study and EIS/EIR were completed December 15, 1998 with the issuance of the Division Engineer’s Public Notice, followed by the Report of the Chief of Engineers in August 1999, and authorization in the 1999
Water Resources Development Act (WRDA). The airfield is being closed under the Base Realignment and Closure (BRAC) process, with the City of Novato acting as the Reuse Authority. Remaining tasks in the BRAC process are; completing the site Risk Assessment, Remediation, and transfer of the airfield property to the California State Coastal Conservancy by the end of FY 2002. The site has existing contamination in the form of hydrocarbon compounds and heavy metals, the magnitude of which is being determined in the Risk Assessment. A Memorandum of Agreement (MOA) has been formalized between the Department of Defense (DOD)/BRAC command and the nonfederal sponsor, the California State Coastal Conservancy (Conservancy) to ensure that the clean up of the site is suitable for wetland restoration for endangered species. The U. S. Army Corps of Engineers, Sacramento District, is managing the environmental cleanup and closure of the base. The Remediation of the States Lands Parcel currently owned by the State of California is being completed under the Formerly Used Defense
Site Program (FUDS). The Remedial Options Study is underway to evaluate the remedies for Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) contaminants found on site.
Due to funding and decision constraints in the BRAC and FUDS programs, the delivery of dredge material to the Hamilton Airfield and State Lands Commission parcel may be delayed. This impact will potentially delay the sequencing of dredge material from the Oakland 50’ Project and other federal navigation channel dredging activities, resulting in aquatic disposal in San Francisco Bay and at the San Francisco Deep Ocean Disposal site. The best alternative beneficial reuse disposal site is the adjacent Bel Marin Keys site.
A pre-construction Engineering and Design (PED) cost sharing agreement was signed in September 1999 between the Corps and the Conservancy. The Project Construction Agreement (PCA) was signed in April 2002 and the first installment of the off loader pipeline across the outbound marsh was completed within the environmental window for
endangered species in January 2002 under the PCA for the Oakland 50’ Deepening Project.
FUTURE EFFORTS: A phased approach has been adopted to complete the design and construction tasks in conjunction with the availability of the real estate parcels and dredge material. Site preparation has begun in FY03 in preparation for receiving the first
deliveries of O&M dredge material in FY04. The adjacent State Lands Commission owned parcel would be remediated under the FUDS program at a future unknown date. An attempt to establish a second MOA for the FUDS parcel between DOD and the Conservancy, to ensure the clean up of the site would be suitable for wetland restoration for endangered species and occur at a future date that met the construction schedule for the rest of the restoration site, failed. An Ecosystem Restoration Initial Appraisal (WRDA 1996, Section 204) completed in October 2000 recommended that the adjacent 1600-acre Bel Marin Keys (BMK) property be studied as a potential addition to the Hamilton Wetlands Project. The Conservancy acquired the BMK parcel. To prevent the loss of dredge material due to the BRAC and
FUDS constraints, the District and the California State Coastal Conservancy completed Feasibility level study tasks and a Supplemental Environmental Impact Statement/Report (SEIS/R) during calendar year 2002 to support a Post Authorization Change document. This document will be required to authorize BMK for construction as a part of the
Hamilton Wetlands Restoration project. The Conservancy expects to use this effort to support adding BMK to a possible Water Resources Development Act of 2004.