2007/06/20 Council Agenda Packet

C EXHIBIT A CITY OF EVERETT DESIGN OF A NEW CLEARWELL AT THE CHAPLAIN RESERVOIR WATER FILTRATION PLANT AMENDMENT 1 SCOPE OF SERVICES The original scope of services for the project was to prepare a preliminary design,final design, and Contract Documents for the construction of a new clearwell for the Chaplain Reservoir Water Filtration Plant (WFP). That phase of the project is nearing completion, and the City of Everett has requested an additional scope of services and fee estimate for additional work performed during the design phase, in addition to the work required to perform office engineering and startup services during the construction phase of the project. This Exhibit A contains the requested scope of work, while Exhibit B contains the accompanying fee estimate. DESIGN PHASE SCOPE ADJUSTMENT During the design phase of the project, the design changed significantly both in complexity and scope, and significant increases in the design costs to address these issues have been incurred. These issues have included: • Existing Poor Site and Soil Conditions • Redesign of the Existing Backwash Pump Station (BWPS) • Clearwell Flow Distribution Structure (CFDS) • CFDS Bypass Pipeline and Hot Tap • Recovered Water Pump Station Improvements • Miscellaneous Design Components • Contract Documents and Project Schedule A brief explanation for each of these items follows: Existing Poor Site and Soil Conditions The initial geotechnical explorations by Shannon & Wilson determined that the clearwell site is underlain by unconsolidated soils as a result of previous landslide debris, with solid foundation located 50 to 60 feet below the existing grade. As a result, additional field investigations (Cone Penetration Tests)were performed to obtain more extensive data to confirm these findings, and 25 H:\Client\Everett_SEA\Contracts\7094A10-Clearwell dgdn\Amend 1 Apr 2007\EXHIBIT A.doc A-1