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permeability). This information will be used to determine if excavation of existing soils is necessary, if more suitable fill must be brought to the site, if a liner system is required to retain water in the reservoir, etc. County will subcontract directly with a licensed and certified geotechnical services contractor to perform standard penetration tests, including soil profile and percolation tests. Consultant proposes that a minimum of 5 soil borings be completed to a minimum depth of 50 feet below land surface, as well as 5 percolation tests across the 68 -acres. The locations of these borings and tests will be determined based on the conceptual layout of the access roads, berms and reservoir so that the locations selected provide the most beneficial information possible. Consultant will review the results of the geotechnical evaluation (contractor's report), and provide an interpretation of these results in the summary report to be provided under Task 7.0. It should be noted that the services provided under this task are not to be considered to be a comprehensive geotechnical investigation of the site. Should the County opt to purchase the property, a far more extensive geotechnical evaluation should be performed to obtain more data needed to complete design. TASK 4.0 PERMITTING EVALUATION Consultant will elaborate on the permitting needs summary prepared in the North County Reservoir Feasibility Study to more closely reflect the specifics of the subject property. Consultant will prepare a summary of applicable permits, permit fees, and potential limitations associated with each permit. The summary will also include an anticipated timeframe needed to obtain each permit (Note: the actual schedule is highly dependent on regulatory review times, requests for additional information, and in some cases, the pre -determined schedule for review committees issuing the permits). TASK 5.0 CONCEPTUAL DESIGN Subtask 5.1 Reservoir System The size of the reservoir system has been established by County staff for this particular effort. Of the 83 - acres available within the primary parcel (additional 5 -acre parcel geometry not conducive to inclusion in the reservoir footprint), approximately 68 -acres are considered suitable from a geometry standpoint for the actual reservoir footprint. The additional 5 -acre parcel can be used for maintenance areas, site access, parking, etc. Therefore, the Consultant's direction from the County is to assume that the largest reservoir possible on a 68 -acre site, assuming a 10 foot side water depth, is to be constructed. All conceptual design and cost estimate components of this effort are based on this assumption. Consultant is not providing any additional evaluation related to sizing of reservoir size. While USGS staff gauge data (historical and instantaneous flow) is available within the South County Relief Canal and rainfall/evaporation data is available from the National Oceanic and Atmospheric Administration, this information is not required during this initial phase if the assumption is that the reservoir will be sized to maximize the available acreage. Coincidentally, the previously completed North County Reservoir Feasibility Study determined that to meet a long-term potable water demand of 5.0 mgd (average daily flow), a reservoir of 64 -acres would be required (with a 10 foot side water depth). Much of the design information and resulting estimates of probable cost for the North County effort are transferable to this evaluation and will serve as the basis of this Task. Consultant will update unit quantities from the previous report to more accurately reflect the current, site-specific evaluation and 68 -acre size (vs. the previous 64 -acre size). Subsequent phases, should the County opt to purchase the property and pursue the reservoir construction, should include A-3 jj1778.docx