Operation and maintenance of dewatering and surface water control systems
(1) Supervision. Supervisory personnel shall be present onsite during normal working hours and shall
be available on call 24 hours a day, 7 days per week, including holidays.
(2) Operating personnel. Sufficient personnel skilled in the operation, maintenance, and replacement of the dewatering and surface water control systems, components, and equipment shall be onsite 24
hours a day, 7 days per week, including holidays, at all times when the systems are in operation.
(3) Well pumping restriction. The pumping rate of any dewatering (deep) well shall be adjusted, if necessary, by adjustment of engine speed or valving so that the water level in no well is lowered below the pump
bowl. With approval of the C. O.R., the pump bowl may be lowered. In order to maintain maximum well efficiency, the deep-well system shall be operated by pumping whatever number of wells are required to achieve the specified water level lowering in the deep sand formation without pumping any well more than 1200 gallons per minute except in an emergency or if required to achieve the specified water level lowering.
(4) Responsibility. Dewatering the excavation includes the control of seepage and artesian pressure in the deep sand stratum underlying the site and the control of seepage from the upper silts and silty sand for the duration of this contract. Included are the operation and maintenance of the deep-well, jet-eductor well, and surface water control systems.
(5) Repair and replacement. The specified number of wells and pumps shall be available for use at all times. All damaged or malfunctioning wells or well components shall be repaired or renewed as expeditiously as possible while continuing to maintain the required water levels. The Contractor shall be responsible for all replacement equipment and the repair and maintenance of all system components so as hmain – tain the system fully operational. Replacement equipment and materials shall conform to the requirements of these specifications.
(6) Maintenance criteria. The Contractor shall maintain a regularly scheduled maintenance program which shall conform with the equipment manufacturer’s recommendations and include all other work necessary to maintain all components fully operational. The maintenance program shall include, but not be limited to, checking the flow rate and water elevation in each well. All data and records shall be submitted to the C. O.R. at the completion of this contract. The Contractor shall also maintain any nonoperating pumps and engines. Maintenance shall include, but not be limited to, starting each nonoperating pump and engine on a weekly basis and operating the pump for a minimum of 15 minutes. All pumps, both operating and nonoperating, shall be tested for wear, independently, on a monthly basis. The Contractor shall conduct a shutoff head test and a test to verify that the pump is capable of operating at its rated head capacity. The Contractor shall renew all pumps having a test result less than 75 percent of the manufacturer’s rated shutoff head or rated capacity. The maintenance tests shall be conducted under the supervision of the Contractor Quality Control representative and under the observation of the C. O.R.
j. Damages. The Contractor shall be responsible and shall repair without cost to the Government, any work in place, another contractor’s equipment, and any damage to the excavation, including damage to the bottom due to heave that may result from his negligence, improper operationand/or maintenance of the
dewatering system, and any mechanical failure of the system.
k. Transfer of system. The succeeding Contractor for Phase III construction, or the Government, shall take title to the complete surface and dewatering systems when the Contractor for Phase II completes his or her work. The facilities to be transferred include all dewatering wells, jet-eductor wells, pumps, engines, gear drives, piezometers, header pipe, valves, and all spare parts and standby equipment pertinent to the surface and groundwater control systems. The dewatering systems shall be continuously operated during the transfer of the system to either the Phase III Contractor or to the Government. The (succeeding) Contractor for Phase III work, or the Government, shall take title to the complete dewatering well, jet – eductor, and surface water control systems as installed when either assumes responsibility for maintaining the excavation dewatered. The Contractor (Phase II) shall not be responsible for removing any of the dewatering systems or grouting of wells or supplemental dewatering facilities, if any, installed by him or her, at the end of his or her contract or subsequently thereafter.