Laserfiche WebLink
3.3 INSTALLATION AND OPERATION <br />A. The dewatering trench/pipe system is to be installed PRIOR to final keyway foundation <br />excavation, at all locations, and with the dimensions shown on the drawings, where <br />excess groundwater is entering the site, to ensure that groundwater infiltration is <br />mitigated and does not affect the integrity of the keyway foundation materials. The pipe <br />shall be secured by methods approved by the Engineer to maintain line and grade. At <br />such locations where excess groundwater is being sufficiently mitigated by prior <br />installation of the dewatering system, the dewatering system can be terminated with a <br />riser pipe installed at the termination point. When excess groundwater resumes entering <br />the site the dewatering system shall be started again, with a riser pipe, and continued <br />until excess groundwater is sufficiently mitigated. <br />B. Same size tees /elbows and riser pipes extending to finish grade elevation shall be <br />installed at a maximum spacing of 500 feet for use as pumping points during dewatering, <br />and grout placement points during abandonment. <br />C. At the ends of the dewatering system, and prior to additional pipe being installed, a <br />trench shall be excavated to direct water being discharged from the system away from <br />the fill area to a sedimentation pond collection point. The water shall then be discharged <br />from the site after the sediment has been removed from the water. <br />D. When the dewatering system does not meet the specified requirements, and as a <br />consequence instability of the slopes or damage to the excavations occurs, the Contractor <br />shall supply all materials, labor, and perform all work for restoration of excavations fill <br />soils, and slopes, to the satisfaction of the Engineer. <br />E. When the dewatering system does not meet the specified requirements, and as a <br />consequence fill surfaces become too wet or the fill exceeds the specified moisture <br />content, the upper materials shall be removed and replaced with suitable materials placed <br />and compacted to meet applicable specifications. Overly wet fills resulting from failed or <br />inadequate dewatering systems shall not be dried out or mixed with dry material and re- <br />worked in -place to meet applicable fill specifications unless otherwise approved by the <br />Engineer. All work, labor, and equipment required to restore the wetted fill and fill <br />surface (as caused by failed or inadequate dewatering practices) to suitable conditions <br />shall be provided by the Contractor and solely at the Contractor's expense and at no cost <br />to the Owner. <br />F. It is understood that in the event of failed or inadequate dewatering systems or <br />components of systems, the system shall be repaired or upgraded and all components <br />relined or replaced as necessary to achieve an adequate dewatering system in an <br />expedient manner. <br />NCCI Pit #1 Reservoir Liner - Technical Specifications Dewatering <br />312319 -3 <br />