An increased usage of Nitrogen to maintain Primary Containment pressure within specification was noticed during steady state operation. Investigation into the extra Nitrogen usage revealed that Primary Containment Leakage was in excess of that allowed per Technical Specification 3.3.3.a. No action statement is provided for leakage in excess of Technical Specification 3.3.3.a; therefore in accordance with Technical Specification 3.0.1, the reactor shall be placed in an operational condition in which the specification is not applicable. This requires the plant to be shutdown and cooled down to less than 216 degrees F.
Additionally, this is reportable as an event or condition that could have prevented fulfillment of a safety function of a system needed to control the release of radioactive material.
Investigation of containment leakage is in progress.
An update will be provided when the plant is in an operational condition in which Technical Specification 3.3.3.a is not applicable.
The licensee has notified the NRC Resident Inspector. Licensee has notified the State of New York.
As of 2333 EST on 12/13/2012, the reactor is below 215 degrees F, and containment is no longer required to be operable by Technical Specification 3.3.3. As part of the shutdown, a manual reactor scram was initiated as part of the pre-planned shutdown sequence and the High Pressure Coolant Injection (HPCI) System automatically initiated as expected. At Nine Mile Point Unit 1, a HPCI System actuation signal on low Reactor Pressure Vessel (RPV) level is normally received following a reactor scram, due to level shrink.
HPCI is a flow control mode of the normal feedwater systems and is not an Emergency Core Cooling System. At 1913 EST, RPV level was restored above the HPCI system low level actuation set point and the HPCI system initiation signal was reset. Pressure control was established on the turbine bypass valves, the preferred system. No Electromatic Relief Valves actuated due to the scram.
Nine Mile Point Unit 1 is currently in Cold Shutdown, with reactor water level and pressure maintained within normal bands. Decay heat is being removed via shutdown cooling (SDC). The offsite grid is stable with no grid restrictions or warnings in effect."
The licensee has notified the NRC Resident Inspector and State authorities. Notified R1DO (Holody) and NRR EO (Lund).