Agmt05 Moffatt & Nichol Engineer

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EXHIBIT IIAII REDWOOD SHORES LAGOON DREDGING PROJECT SCOPE OF SERVICES - MOFFATT & NICHOL The services described in this scope of work consist of providing engineering design, permit support, and construction support for the dredging of the Redwood Shores Lagoon. A phased approach to completing the scope of work is described, to facilitate the City with planning and budgeting, as well as public outreach and procurement of construction funds. A description of individual tasks, along with anticipated schedule and deliverables is provided below. PHASE 1: PRELIMINARY DESIGN The objective of this phase is to develop a preliminary design that defines project scope and identifies constraints and budgets. This phase encompasses data collection and preliminary design, including an assessment of lagoon depths, dredging volumes and location, sediment properties, construction techniques, and planning level project costs, as well as presenting the project to regulatory and resource agencies for initial feedback on the project. The following specific tasks are envisioned. Task 1.1 - Review Existing Data and Reports This task includes collection of existing information including lagoon history, original construction drawings and methods, water quality and circulation studies, utility maps, and the recent hydrographic survey of the lagoon. We expect the thickness of dredge cut (bank) to be small, which implies that the accuracy of the soundings collected for the hydrographic survey is critical. We will coordinate with the City's hydrographic surveyor to assess limitations of the survey, and conduct a field visit to verify critical elements of the lagoon including toe of embankment slopes, invert elevations of culverts and gates, and water level recordings. We will meet with City staff from Public Works to verify lagoon operations and maintenance activities, and to discuss needs and objectives of the project. The recreational and navigational uses of the lagoon will be investigated to identify opportunities and constraints to dredging. Task 1.2 - Prepare Initial Dredging Assessment The intent of the Assessment is to provide enough information to serve as the basis for conducting the sediment characterization tasks described below, and for discussions with the Dredged Material Management Office (DMMO) related to the Sediment Sampling and Analysis Plan. The Initial Dredging Assessment will include: . Preparation of a base-map on an aerial photo background to serve as the basis for area and volume calculations; . A description of ongoing sedimentation processes based on a review of the hydrographic survey, water quality reports, and weed-control maintenance records; . Approximate volumes and locations of material that could be dredged; . Location and descriptions of potential disposal sites; . Means and methods of dredging, transport and disposal; . Range of construction costs, at a concept level, to assist with project definition. Options for phasing the project, and/or different sizes of projects will be evaluated. 1