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Immediate "Work Plan": <br />The followings steps by CC&V were taken immediately to minimize the flow of water to the Phase IVb <br />LVSCS sump and to manage the increase flow of water that was noted at the sump: <br />1. The PSSA operating level was immediately decreased. <br />2. Phase IVb LVSCS Pump #1 was replaced. It was determined that its performance was around <br />approximately 55 gpm. Typically, the flowrate recorded from this system is approximately 58 <br />gpm. <br />3. A variable frequency drive ("WD") was installed to control Phase IVb LVSCS Pump #1. <br />4. The pumping rate for Phase IVb LVSCS Pump #I was also increased by using the VFD to "over- <br />speed" the pump/motor assembly by increasing the frequency to slightly over 60 Hz. CC&V first <br />confirmed that this activity was within the pump/motor manufacturer specifications, and that <br />there was no significant potential for decreasing pump/motor assembly life. <br />5. The gas-powered booster pump was used to augment the pumping rate of Pump # 1. <br />6. A hard-piped electric booster pump was purchased and installed to maximize the performance of <br />Phase IVb LVSCS Pump #1. <br />These immediate efforts increased the pumping capacity of Phase IVb LVSCS Pump #1 system from <br />approximately 55 gpm to 60 gpm. As a result, the hydrostatic head level within the LVSCS declined <br />within the Phase IVb LVSCS sump to below the 2' level, and has remained below that level. <br />Permanent "Work Plan": <br />As part of a more "permanent solution," CC&V has implemented or is implementing the following to <br />increase the Phase IVb LVSCS Pump #1 recovery capacity from approximately 60 gpm to approximately <br />100 gpm. The work includes: <br />1. Pump/motor assembly hertz readings and flowrate data are being monitored at a minimum of <br />once per shift at both Pump #1 and Pump #2 at the Phase IVb LVSCS to enable CC&V personnel <br />to observe and quantify any potential increases in flow of water at the sump. This is a permanent <br />change in procedure and was implemented on October 9, 2009. <br />2. CC&V commissioned fabrication of a high density polyethylene ("HDPE") pipe to replicate the <br />specified, in-place pipe into the bottom of the sump at Phase IVb LVSCS. This was completed <br />and arrived at site on October 13, 2009. This will allow CC&V personnel to ensure that any <br />future pump/motor assembly will be physically able to be both placed and removed in the sump <br />associated with the Phase IVb LVSCS. <br />3. CC&V evaluated and replaced the existing 5 hp pump/motor assembly for Pump #I with a "new" <br />7.5 hp pump/motor assembly capable of pumping approximately 100 gpm from the Phase IVb <br />LVSCS sump. This work was completed on November 3, 2009. <br />4. A method to appropriately affix the hydrostatic head monitoring transducer to the new 7.5 hp <br />pump/motor assembly and to properly cool the new pump/motor assembly (in the form of a new <br />shroud) was evaluated and fabricated for the new Pump #1 in Phase IVb LVSCS. This was <br />included in the pump/motor installation that occurred on November 3, 2009. <br />5. CC&V confirmed the existing Pump #1 VFD, rated for 10 hp pump/motor assembly, was capable <br />of operating the new 7.5 hp pump/motor assembly. Factors such as pump demand, elevation, <br />wire size, and wire length needs were analyzed as part of this confirmation. If later determined <br />necessary, a larger VFD will be purchased. <br />6. CC&V evaluated the existing electrical wire feeding Pump #1 and upgraded the existing system <br />to be in line with the operating current of the new 7.5 hp pump/motor assembly during <br />installation on November 3, 2009.