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1.03 DEFINITIONS <br /> A. Groundwater control includes both dewatering and depressurization of — <br /> water-bearing soil. <br /> B. Dewatering includes lowering the water table and intercepting seepage which — <br /> would otherwise emerge from slopes or bottoms of excavations, and disposing of <br /> removed water. The intent of dewatering is to increase stability of excavated <br /> slopes; prevent dislocation of material from slopes or bottoms of excavations; _. <br /> reduce lateral loads on sheeting and bracing; improve excavating and hauling <br /> characteristics of excavated material; and prevent failure, heaving, or pumping of <br /> the bottom of excavations. <br /> C. Depressurization includes reduction in piezometric pressure within soil strata not <br /> controlled by dewatering alone, as required to prevent failure, heaving, or _ <br /> pumping of excavation bottom or instability of excavations. <br /> D. Excavation drainage includes keeping excavations free of surface water, <br /> seepage water, and exfiltration from existing pipes and structures. <br /> E. Surface drainage includes use of temporary drainage ditches and dikes and <br /> installation of temporary culverts and sump pumps with discharge lines as _ <br /> required to protect the work from any source of surface water. <br /> F. Equipment and instrumentation for monitoring and control of the dewatering _ <br /> system includes piezometers and monitoring wells, and devices, such as flow <br /> meters, for observing and recording flow rates. <br /> 1.04 PERFORMANCE REQUIREMENTS <br /> A. Contractor shall conduct subsurface investigations to identify groundwater <br /> conditions and to provide parameters for design, installation, and operation of — <br /> groundwater control systems. <br /> B. Design a groundwater control system, compatible with requirements of all laws _ <br /> and regulations to produce the following results: <br /> 1. Effectively lower groundwater levels, reduce piezometric pressures, and <br /> eliminate infiltration of water. <br /> 2. Lower and maintain groundwater to levels at least three feet below the <br /> bottoms of excavations and to lower elevations if under foundation <br /> structures as required to obtain compaction. Develop substantially dry <br /> and stable subgrades for subsequent earthwork compaction and <br /> construction operations. <br /> 3. Preclude damage to adjacent properties, buildings, structures, utilities <br /> and other work. — <br /> 4. Prevent the loss of fines, seepage, boils, quick conditions, or softening of <br /> the foundation soils. — <br /> Division III-49 NEI Phase II Water and Sewer <br /> July 2007 CIP Nos. 7468, 7589,7590 <br />