Dewatering

(1) General. The dewatering system shall be of a sufficient size and capacity as required to control hydrostatic pressure on all clay strata below elevation – 13.0 feet to depths indicated by the logs of borings, to permit dewatering of the area specified in para­graph d below, and to allow all material to be exca­vated, piles driven, and concrete placed, all in a dry condition. The system shall include a deep-well sys­tem, a wellpoint system, other equipment, appurte-

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nances, and related earthwork necessary for the re­quired control of water. The sequence of installation of components of the dewatering system shall be in ac­cordance with the specifications and drawings. The system shall remain in continuous operation, as speci­fied, until a written directive to cease dewatering oper­ations has been received from the Contracting Officer.

(2) Control of water. The Contractor shall control, by acceptable means, all water regardless of source. Water shall be controlled and its disposal provided for at each berm. The entire periphery of the excavation area shall be ditched and diked to prevent water from entering the excavation. The Contractor shall be fully responsible for disposal of the water and shall provide all necessary means at no additional cost to the Gov­ernment.

b. Design. The dewatering system shall be designed using accepted and professional methods of design and engineering consistent with the best modern practice. The dewatering system shall include the deep wells, wellpoints, and other equipment, appurtenances, and related earthwork necessary to perform the function.

A representative of the Contractor shall visit the site to determine the conditions thereof. The Contractor shall be responsible for the accuracy of the drawings and design data required hereinafter.

(1) Drawings and design data. The Contractor shall submit for the approval of the Contracting Of­ficer, within 30 calendar days after receipt of Notice to Proceed, drawings and complete design data showing methods and equipment he or she proposes to utilize in dewatering, including relief of hydrostatic head, and in maintaining the excavation in a dewatered and in a hydrostatically relieved condition. The material to be submitted shall include, but not necessarily be limited to, the following:

(a) Drawings indicating the location and size of berms, dikes, ditches, all deep wells, observation wells, wellpoints, sumps, and discharge lines, including their relation to water disposal ditches.

(b) Capacities of pumps, prime movers, and standby equipment.

(b) Design calculations proving adequacy of sys­tem and selected equipment.

(d) Detailed description of dewatering proce­dure and maintenance method.

(2) Responsibility. Approval by the Contracting Officer of the plans and data submitted by the Con­tractor shall not in any way be considered to relieve the Contractor from full responsibility for errors therein or from the entire responsibility for complete and adequate design and performance of the system in controlling the water level in the excavated area and for control of the hydrostatic pressures to the depths hereinbefore specified. The Contractor shall be solely responsible for proper design, installation, proper

operation, maintenance, and any failure of any compo­nent of the system.