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Pursuant to 50.73(a)(1) the following info … Pursuant to 50.73(a)(1) the following information is provided as a sixty (60) day telephone notification to the NRC. This notification, reported under 50.73(a)(2)(iv), is being provided in lieu of the submittal of a written LER (Licensee Event Report) to report a condition that resulted in an invalid actuation of the high pressure coolant injection (HPCI). At Nine Mile Point Unit 1, HPCI is a flow control mode of the normal feedwater system and is not an emergency core cooling system. </br>On March 19, 2018 Nine Mile Point Unit 1 (NMP1) was at 0 percent power and in cold shutdown in support of a planned maintenance outage. At approximately 0118 (EDT), a reactor water level transient initiated by the fill and vent of 12 Reactor Recirculation Pump (12 RRP) occurred. During the fill and vent, Reactor Pressure Vessel (RPV) level lowered quickly from the initial level of 68 inches and a low level alarm was received. Control Room Operators reduced Reactor Water Clean-Up (RWCU) reject flow to turn the level trend and clear the low level alarm generated off of the compensated, GEMAC, level instrumentation. RWCU reject flow was reduced by 50 percent which caused RPV level to start to rise. RPV level was raised to approximately 72 inches at which time the Reactor Operator began to raise reject flow to reestablish the normal level band. During the RPV level transient, with actual water level at 74 inches on the GEMAC, the Yarway level instrumentation, which is not density compensated and therefore invalid, reached 92 inches causing an invalid high RPV water level turbine trip signal and associated invalid HPCI initiation signal. At no point in time did actual RPV water level reach the high RPV water level turbine trip set point of 92 inches. The potential for a turbine trip signal to occur due to shutdown activities was understood and tags were hung to lockout the Feedwater Pumps to prevent the HPCI start signal. Therefore, no HPCI injection occurred. </br>The Licensee has notified the NRC Resident Inspector.e has notified the NRC Resident Inspector.
04:00:00, 19 March 2018 +
53,584 +
17:18:00, 6 September 2018 +
04:00:00, 19 March 2018 +
Pursuant to 50.73(a)(1) the following info … Pursuant to 50.73(a)(1) the following information is provided as a sixty (60) day telephone notification to the NRC. This notification, reported under 50.73(a)(2)(iv), is being provided in lieu of the submittal of a written LER (Licensee Event Report) to report a condition that resulted in an invalid actuation of the high pressure coolant injection (HPCI). At Nine Mile Point Unit 1, HPCI is a flow control mode of the normal feedwater system and is not an emergency core cooling system. </br>On March 19, 2018 Nine Mile Point Unit 1 (NMP1) was at 0 percent power and in cold shutdown in support of a planned maintenance outage. At approximately 0118 (EDT), a reactor water level transient initiated by the fill and vent of 12 Reactor Recirculation Pump (12 RRP) occurred. During the fill and vent, Reactor Pressure Vessel (RPV) level lowered quickly from the initial level of 68 inches and a low level alarm was received. Control Room Operators reduced Reactor Water Clean-Up (RWCU) reject flow to turn the level trend and clear the low level alarm generated off of the compensated, GEMAC, level instrumentation. RWCU reject flow was reduced by 50 percent which caused RPV level to start to rise. RPV level was raised to approximately 72 inches at which time the Reactor Operator began to raise reject flow to reestablish the normal level band. During the RPV level transient, with actual water level at 74 inches on the GEMAC, the Yarway level instrumentation, which is not density compensated and therefore invalid, reached 92 inches causing an invalid high RPV water level turbine trip signal and associated invalid HPCI initiation signal. At no point in time did actual RPV water level reach the high RPV water level turbine trip set point of 92 inches. The potential for a turbine trip signal to occur due to shutdown activities was understood and tags were hung to lockout the Feedwater Pumps to prevent the HPCI start signal. Therefore, no HPCI injection occurred. </br>The Licensee has notified the NRC Resident Inspector.e has notified the NRC Resident Inspector.
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00:00:00, 6 September 2018 +
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