2022/03/02 Council Agenda Packet

City of Everett Water Treatment Plant Portal 4 Improvements I Scope of Work control of Consultant. Actual bids received and costs incurred may vary from the estimate ranges prepared by Consultant. All estimates are expressly implied to have 90 to 95% confidence limits. • Task includes a contingency for a third party review of the geotechnical reports (Earth Mechanics). Meetings • Final design (90%) review workshop. Assume workshop will be attended by six BC staff for a duration of two hours. • Assume three site visits attended by two BC staff for a duration of four hours on site. Work Products • This task includes development of final (90%) and bid (100%) design documents. The design plan set will include approximately 34 drawings including general sheets, notes, symbols and legends, and specifications. • The Issue for Bid deliverable will contain all drawings and specifications required for bidding. The Issue for Bid package will be stamped/sealed and digitally signed. Issue for Bid Documents will be provided in electronic format for full-size and half-size document production. • CAD files of final designs. • AACEI Class 1 construction cost estimate. Task 601 Geotechnical Services Activities/Approach: Provide geotechnical services in support of the design of the new valve vaults and vaults and to assess condition of the slope above the Portal 4 structure. The following section summarizes the geotechnical scope of work. A full description of the geotechnical services is included as Attachment A. • Review existing geotechnical reports and data for the project area. • Explore and classify the subsurface soil conditions within the vicinity of the proposed valve and vault installation locations. • Investigate the slide on the hill side southeast of the Portal 4 structural to inform mitigation. This investigation will provide information for general site and/or slope stability modifications. • Develop geotechnical engineering recommendations for design and construction of the new valve and vault locations, including: o Construction dewatering o Temporary excavation slopes/support o Vault foundations o Groundwater elevations o Structural fill o Seismic considerations • Two(2) geotechnical borings (40 feet deep) at the location of the valve/vaults and one (1) geotechnical boring (60-80 feet deep) near the slide on the hill side southeast of the Portal 4 structure. Everett Responsibilities • Provide site access, staffing, and resources to support field work conducted by geotechnical crews. Task Assumptions • Geotechnical investigations require two site visits for utility locates prior to the field explorations. Page 9 of 13