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drawings . If CDM' s services are not necessary, this task will include only the surveying of the well site and proposed pipeline corridor once the well location is finalized by County staff. TASK 3. 0 WELL NO. 7 DESIGN Subtask 3 . 1 Well Construction Details CDM will base the design of the new well on the well construction details of the most recently constructed Well No . 3 at the South County WTP, available hydrogeologic data, and input from the County and SJRWMD . This information will be used to most accurately identify the production zones and estimate the casing depth (both surface casing and well casing) and total depth for the new well . It is anticipated that the production well will be 164nches in diameter, which is consistent with the current permitted size of Well No . 7. The well construction methods and materials will be specified to be consistent with the existing production wells or as otherwise requested by County staff. It is anticipated that the cased depth of the new well will be between 350 and 400 feet below land surface, and the total depth will range between 700 and 730 feet below land surface . Well depth will be adjusted to maximize the productivity of the well. Several logs will be required to be completed by the contractor upon completion of the open hole including gamma ray, resistivity, and caliper logs, as well as a television survey to document the condition of the open hole . CDM will witness the completion of each log. Subtask 3 . 2 Wellhead and Appurtenances This subtask will provide for the design of the pump, motor, column pipe, line shaft, bearings, discharge head, mechanical seal, motor, pressure relief valves, blow off valves, flow meter, drawdown transducer, pressure gauges, discharge piping, pad, support pedestals, and other appurtenances associated with the above-ground components of the wellhead . The configuration of the wellhead will be consistent with the design of the County' s recently reconfigured South County WTP (specifically Well No . 3) wells unless otherwise directed by County staff. The wellhead design will also include provisions for a control panel, main disconnect, remote operation, and emergency power connection (via plug-in receptacles) . Dedicated emergency power for the new site will not be included in the contract documents, since the County owns portable generators that can be moved between sites as needed . Subtask 3 . 3 Raw Water Piping CDM will design the raw water piping from the new well site to the existing WTP (or to the nearest manifold raw water pipe) in a manner consistent with the current raw water piping. Ultimate design of the raw water piping will be dependent on the well site identified in Task 2. 0. Every effort will be made to connect the new well to existing manifolds, if physically and hydraulically feasible, to minimize expense to the County . The raw water piping will include isolation valves and air release valves as necessary to maximize operational flexibility . TASK 4. 0 INSTRUMENTATION AND PROGRAMMING The new instrumentation, programming and controls associated with Well No . 7 will require integration into the WTPs' SCADA systems and PLC . The integration will involve modifications to the SCADA system to include control screens for the new well and additional modifications to incorporate telemetry readings for flow, drawdown, remote operation capabilities, and required alarming. A-2 j12355.doc