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BACKGROUND The City's wastewater collection system consists of four major trunk sewer pipelines that are tributary to the Dublin San Ramon Services District (DSRSD) wastewater treatment plant. One of these major trunk lines is the East Amador Trunk Sewer (EATS) that serves the north and northeastern area of the City. The diameter of the EATS trunk pipeline varies from 18 inches to 30 inches, beginning at Santa Rita Road just north of Stonridge Drive and terminating at the EATS pump station located at the DSRSD treatment plant. The EATS line was identified as capacity deficient in the City's 2007 Wastewater Master Plan. Currently there is an inactive sewer pipeline called the East Amador Relief Sewer (EARS) which was constructed in 1984 by the Developer (Prudential) in anticipation of a future high demand land use development in the Hacienda Business Park area, and to relieve the flow from the EATS line. The EARS line is a 30 to 36 inch diameter pipe that begins near the intersection of Santa Rita Road/Stoneridge Drive on the east end, and terminates at the west end on the open parcel at the southeast corner of the Stoneridge Drive/Johnson Drive intersection. The depth of this pipe line is approximately 30 feet below the surface at the west end. DISCUSSION Consultant Selection A Request for Qualifications (RFQ) was prepared, seeking a qualified firm to provide specialized engineering services required to develop the necessary detailed plans and specifications for a new pump station. These services include geotechnical, survey, structural, hydraulic, civil, mechanical, and electrical engineering functions. Four firms responded to the RFQ. After interviews and evaluation of the submitted qualifications, City staff determined Carollo Engineers to be the most qualified firm for the project. The interviews and proposals were evaluated on presentation, project understanding, project approach, and previous related experience of both the project members and the firm. After the selection process, staff discussed the project's objective and determined that the scope of work will be divided into two phases. The first phase of this work is to verify the parameters of the design, including pump station size and proper operation of both pipelines. Phase one will include conversion of the hydraulic model to an updated software system, hydraulic analysis of the EARS and EATS sewer collection pipelines, evaluation of the impacts of cross-over connections to the collection system, as well as review of pump station site size constraints and the capacity of the new pump station. Carollo Engineers has proposed to perform phase one for a "not-to-exceed" amount of $38,000. Staff has reviewed the tasks and associated fees and found them to be reasonable. Previous work performed by Carollo Engineers has been verified as satisfactory. After the first task is completed, staff will discuss and negotiate the new scope of work for phase two with Carollo Engineers. Phase two includes the development of the necessary detailed plans and specifications for award of a construction contract. The Page 2 of 3