Semantic search

The following information was provided by the licensee via email: At 1000 EDT on March 14, 2023, during valve diagnostic testing, the high pressure core injection (HPCI) lube oil cooling water supply isolation valve did not stroke open. This failure resulted in the Unit 2 HPCI system being inoperable. This is being reported as a loss of an entire safety function condition in accordance with 10CFR50.72(b)(3)(v)(D). The licensee notified the NRC Resident Inspector.

• * * RETRACTION FROM BOB BINGMAN TO BILL GOTT AT 2208 EDT ON 04/02/2023 * * *

The following information was provided by the licensee via email: The purpose of this notification is to retract event notification (EN) 56409 reported on 03/14/2023. On March 09, 2023, Susquehanna Unit 2 entered a routine high pressure core injection (HPCI) maintenance outage. In support of this system outage, Technical Specification (TS) 3.5.1, Condition D was entered for an inoperable HPCI system. On March 14 as reported in EN 56409, the HPCI lube oil cooling water supply isolation valve did not electrically stroke open following engagement of manual clutch lever. Specifically, to support the maintenance evolution, electricians declutched the valve actuator to move it from the motor/electric operational mode to the manual operational mode as part of planned valve diagnostic data collection. In this testing configuration (i.e., manual operational mode), an attempt to electrically stroke the valve was made, resulting in the valve failure to stroke. Prior to this maintenance evolution, the HPCI lube oil cooling water supply isolation valve was found in the expected full-closed position with the motor/electric operational mode enabled, meaning prior to the HPCI maintenance outage, the affected valve was operating as designed and capable of performing all design functions. The described condition was therefore determined to be the result of the maintenance activity. NUREG-1022, Section 3.2.7, states: 'reports are not required when systems are declared inoperable as part of a planned evolution for maintenance or surveillance testing when done in accordance with an approved procedure and the plant's TS (unless a condition is discovered that would have resulted in the system being declared inoperable).' Following completion of investigation and repair, Susquehanna determined that, per NUREG-1022, Section 3.2.7, the event was not reportable. HPCI was declared inoperable as part of a maintenance evolution which was done in accordance with an approved procedure and the TS. The described condition was not a pre-existing condition that would have resulted in the system being declared inoperable prior to the planned maintenance activity. Notified R1DO (Schroeder)

At 1248 EST, Unit 2 High Pressure Coolant Injection (HPCI) system was being tested for routine quarterly flow verification using surveillance test procedure SO-252-002. When HPCI turbine speed was lowered to approximately 2400 RPM, oscillations on turbine speed, flow and discharge pressure were observed. HPCI turbine speed was raised to approximately 2700 RPM and the oscillations stopped. Unit 2 HPCI system had been declared inoperable and LCO 3.5.1 entered at 1200 EST for the surveillance test. (This is a 14 day LCO.) Review by Engineering determined that cause of the oscillations warrant further evaluation and HPCI remains inoperable. HPCI is a single train Emergency Core Cooling Safety system. This event results in the loss of an entire safety function which requires an 8 hour ENS notification in accordance with 10CFR50.72(b)(3)(v).

There are no other ECCS systems presently out of service. The licensee notified the NRC Resident Inspector.

• * * RETRACTION FROM DARVIN DUTTRY TO JOHN SHOEMAKER AT 1201 EST ON 1/17/14 * * *

NUREG-1022, Revision 3, states, 'if the retraction or cancellation of a report under this criterion is due to a revised operability determination, the retraction or cancellation should discuss the basis for why the operability determination was revised, and why it is believed that system operability was never lost (i.e., in lieu of the initial determination).' As indicated in the initial report, Engineering determined that the cause of the oscillations required further evaluation and HPCI remained inoperable. Additional evaluation by Engineering resulted in a conclusion that HPCI was OPERABLE with the observed oscillations at the low flow conditions. Details are as follows: HPCI speed/flow oscillations at low flow conditions can occur due to inherent instability at these conditions. This phenomenon is understood and documented in industry OE (Operating Experience), EPRI (Electric Power Research Institute) maintenance guidelines, and station procedures. HPCI system operation and control during the surveillance were as expected and demonstrated proper response and stable operation, with the only exception being the described oscillations at the low flow condition. This was confirmed by a review of the system response on the start-up traces. A system walkdown confirmed no abnormality with the control system equipment or governor setting. No tuning adjustments were considered to be necessary based on the low magnitude of the oscillations and their negligible impact on system operation. Unit 2 HPCI was declared OPERABLE and LCO 3.5.1 was cleared at 2308 (EST) on December 6, 2013. Based on the above additional information, PPL (Pennsylvania Power and Light) is retracting this report. The licensee has notified the NRC Resident Inspector. Notified the R1DO (Rogge).

At 1350 on 12/14/2012, both Control Structure Chillers at Susquehanna were rendered inoperable. This event required entry into Tech Spec 3.0.3 for both Units. Per Susquehanna procedures, after 1 hour, a power reduction must be commenced. Tech Spec 3.0.3 requires that action be taken within one hour to place the Unit in Mode 3 within 13 hours and Mode 4 within 37 hours. Physical power reduction commenced at 1453 for Unit 1 and 1459 for Unit 2. The 'A' Control Structure Chiller was previously inoperable for routine maintenance. The system was in service for post maintenance testing and activities were underway to swap to the opposite train to allow removal of test instrumentation and fan belt tensioning for equipment associated with the 'A' Control Structure HVAC system. At 1350, the 'B' Control Structure loop circulating pump tripped, rendering the 'B' Control Structure Chiller inoperable. This condition requires immediate entry into Tech Spec 3.0.3. Both Control Structure Chillers are inoperable and this report is being made per 10CFR50.72(b)(2)(i) as a shutdown required by Tech Specs, and 10CFR 50.72(b)(3)(v)(D), Loss of a Safety Function required to mitigate the consequences of an accident. Efforts are underway to restore at least one system to operable status in parallel with Unit shutdown activities. The licensee has notified the NRC Resident Inspector, and will be notifying the State of Pennsylvania.

• * * UPDATE FROM ALEX MCLELLAN TO JOHN KNOKE AT 2228 EST ON 12/14/12 * * *

On 12/14/12 at 1500 EST Susquehanna Steam Electric Station reported a shutdown had been commenced at 1453 EST for Unit 1 and 1459 EST for Unit 2 due to inoperability of both Control Structure Chillers. At 1750 EST the 'A' Control Structure Chiller was declared operable and LCO 3.0.3 was exited. Power reduction for both Units was halted at 1750 and preparations for power restoration initiated. On 12/14/12 Unit 1 power was restored to 98% at 1819 EST and Unit 2 power was restored to 98% at 1943 EST, the maximum power output possible based on grid conditions for Unit 1 and thermal limits for Unit 2. The licensee has notified the NRC Resident Inspector. R1DO (Holody) notified.

On 06/04/2011, personnel observed the temperature control valve for the 'B' control structure chiller not operating properly. To investigate control valve operation, the controller was taken to the manual mode (from automatic) at 1614 (EDT). The control valve stem was lubricated, and the valve was operated with the controller in the manual mode. The 'B' control structure chiller was inoperable in this condition until control valve responsiveness was validated (total of 35 minutes, until 1649 (EDT)). The 'B' chiller continued to operate during this period. The 'A' control structure chiller was out of service during this timeframe to perform maintenance activities. Hence, neither chiller was operable. The control structure chillers provide control building habitability during unit operation. The control structure chillers also provide cooling water for emergency switchgear room cooling on unit one only. This condition is being reported as an event or condition that could have prevented fulfillment of a safety function per 10CFR 50.72(b)(3)(v)(D). The licensee has notified the NRC Resident Inspector.

• * * RETRACTION ON 7/22/2011 AT 1519 FROM LONNIE CRAWFORD TO MARK ABRAMOVITZ * * *

On June 4, 2011, Susquehanna reported the simultaneous inoperability of both control structure (CS) chillers as an event or condition that could have prevented fulfillment of a safety function in accordance with 10CFR 50.72(b)(3)(v)(D). After further investigation, Susquehanna has concluded that the 'A' and 'B' CS chillers were not inoperable at the same time. On June 3, 2011 at 1608, fluctuating amperage was observed on the 'A' CS chiller and the chiller was declared inoperable. As a result, the 'B' CS chiller was placed in service with the 'A' CS chiller placed in standby. Subsequent troubleshooting of the 'A' CS chiller included replacing the chiller temperature controller with a spare while the original controller was evaluated in the shop. The original controller was re-installed on June 4, 2011 at approximately 1030 but did not resolve the issue. The 'A' CS chiller was later shutdown and removed from standby on June 4, 2011 at 1727. Originally, Susquehanna believed that the fluctuating amperage on the 'A' chiller was an operability issue. Subsequent engineering evaluation has determined that the observed oscillations were not rapid enough and did not have sufficient amplitude to cause damage to the chiller motor and were within design limits. The conclusion is that the 'A' control structure chiller was operable and would continue to operate for its 30 day mission time with the observed current oscillations. Although the 'A' chiller was inoperable as a result of troubleshooting at various times on June 3 and 4, the 'A' chiller was available and operable during the short period of time on June 4 when the 'B' chiller was inoperable. . Based on the above information, this ENS report is retracted. The licensee notified the NRC Resident Inspector. Notified the R1DO (Dentel).

On Monday, January 3, 2011, at 1344 EST, it was discovered by engineering that a single point of vulnerability exists at Susquehanna Steam Electric Station affecting both Unit 1 and Unit 2. A potential single HVAC control component has been discovered whose failure could result in a spurious Steam Leak Detection (SLD) isolation causing a loss of generation, loss of the normal heat sink (main condenser) and a loss of HPCI and RCIC. The SLD delta temperature (delta T) instrumentation is dependent on proper operation of the Unit 1 and Unit 2 RB (Reactor Building) HVAC heater temperature controller during cold weather operation. The Unit 1 and Unit 2 RB HVAC heaters are controlled by a single temperature controller which sends a signal to multiple step controllers. Failure of the temperature controller could cause the heaters to turn off. This would cause a significant decrease in RB HVAC supply temperature which results in a significant increase in measured SLD delta T during cold winter months. This could cause an isolation of the MSIVs, HPCI, RCIC and RWCU within a short period of time. This is reportable pursuant to 10CFR50.72(b)(3)(v) for a condition that at discovery could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident and 10CFR50.72(b)(3)(ii) for and event that resulted in the nuclear power plant being in an unanalyzed condition. The licensee notified the NRC Resident Inspector.

• * * UPDATE FROM TODD CREASY TO JOE O'HARA AT 1310 ON 2/28/11 * * *

On January 3, 2011, SSES reported the discovery of a single point vulnerability that affected both Unit 1 and Unit 2 (EN # 46519). The vulnerability involved failure of a temperature controller that had the potential to result in a Steam Leak Detection (SLD) isolation causing a loss of generation, loss of the normal heat sink (main condenser), and a loss of HPCI and RCIC. The condition was reported pursuant to 10CFR50.72(b)(3)(v) as a condition that at discovery could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident and pursuant to 10CFR50.72(b)(3)(ii) as an event that resulted in the nuclear power plant being in an unanalyzed condition. SSES has further evaluated the condition and determined that the condition did not meet reporting criterion 10CFR50.72(b)(3)(v) for a condition that at discovery could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident. The level of judgment in reporting under this criterion Is a reasonable expectation of preventing fulfillment of a safety function. Alternately stated, the condition is reportable if there was reasonable doubt that the safety function would have been fulfilled if the system had been called upon to perform it. Technical evaluation of the condition concluded the following: there is reasonable assurance (high degree of confidence) that the HPCI, RCIC, Main Steam Isolation and RWCU systems will remain operable. The identified condition does not adversely affect the operability of the affected systems. The identified condition increases the probability that a failure of the Reactor Building HVAC temperature controller TC-17589 or TC-27589 could cause the MSIV's, HPCI and RCIC to isolate during cold weather operation. However, this increase in probability is very small and is not sufficient to erode the confidence in the reasonable expectation of operability. For a system isolation to occur, the heater controller had to fail and concurrently the outside air temperature had to be below approximately 10?F. The Reactor Building HVAC temperature controllers are highly reliable and the outside air temperatures required for this event occur infrequently (there have only been 11 instances of temperatures at Susquehanna dropping below 10 deg F in the past two years). Since both infrequent conditions have to occur concurrently, it is unlikely that this postulated failure would occur. As a result, reporting pursuant to 10CFR50.72(b)(3)(v) is retracted; however, the condition remains reportable pursuant to 10CFR50.72(b)b)(3)(ii) as an event that resulted in the nuclear power plant being in an unanalyzed condition. The NRC Resident Inspector has been notified. Notified R1DO (T.Dimitriadis)

• * * UPDATE FROM DAVE BORGER TO HOWIE CROUCH AT 1220 EDT ON 6/7/2011 * * *

On January 3, 2011, SSES reported the discovery of a single point vulnerability that affected both Unit 1 and Unit 2 (EN #46519). The vulnerability involved failure of a temperature controller that had the potential to result in a Steam Leak Detection (SLD) isolation causing a loss of generation, loss of the normal heat sink (main condenser), and a loss of HPCI and RCIC. The condition was reported pursuant to 10CFR50.72(b)(3)(v) as a condition that at discovery could have prevented fulfillment of a safety function needed to mitigate the consequences of an accident and pursuant to 10CFR50.72(b)(3)(ii) as an event that resulted in the nuclear power plant being in an unanalyzed condition. On February 28, 2011, SSES retracted the 10CFR50.72(b)(3)(v) portion of the report on the basis that there was reasonable assurance that the HPCI, RCIC, Main Steam Isolation and RWCU systems would remain operable. The reasonable assurance was based on the very small probability of system isolation that required failure of the highly reliable heater controller had to fail concurrent with outside air temperature below approximately 10?F. This notification is intended to revise the basis for retraction of the 10CFR50.72(b)(3)(v) portion of the report. The revised basis is that the conditions required to prevent fulfillment of a safety function did not exist at the time of discovery. The licensee has notified the NRC Resident Inspector. Notified R1DO (Rogge).

At 1848 on 09/18/2008, the control room was notified by system engineering that insulation was missing from the bottom of the HPCI turbine that could result in nearby electronic components being subjected to higher than design temperatures. This could challenge the ability of the HPCI system to perform its design function for the prescribed mission times. The condition does not prevent the high pressure coolant injection system from automatically starting and injecting during an accident. The longer term ability of the system to continue to inject is challenged by the existing condition. The HPCI system was immediately declared inoperable while engineering continues to evaluate the condition to determine if an actual loss of design function has occurred. This is being reported as an event or condition that could have prevented fulfillment of a safety function required to mitigate the consequences of an accident in accordance with 10CFR50.72(b)(3)(v)(D). The licensee notified the NRC Resident Inspector.

• * * RETRACTION ON 11/12/2008 AT 1616 FROM MARTIN LICHTNER TO MARK ABRAMOVITZ * * *

On September 18, 2008, PPL Susquehanna LLC reported a potential loss of the HPCI safety function under the provisions of 10CFR50.72(b)(3)(v)(D). The report was made when it was discovered that insulation was missing from the bottom of the Unit 2 HPCI turbine. This situation raised concerns that increased area temperatures could adversely affect nearby electronic equipment needed to support long-term HPCI operation. A subsequent investigation has determined that all potentially affected components were rated for operation at temperatures greater than those anticipated during HPCI operation with the missing insulation. An additional physical inspection confirmed that there was no abnormal discoloration or visible signs of accelerated thermal aging on the components and wires in question. It has therefore been concluded that HPCI operability had not been impacted by the missing insulation. Accordingly, the loss of safety function reported on September 18th under ENS # 44503 is being retracted. The insulation has since been restored to the HPCI turbine. The licensee notified the NRC Resident Inspector. Notified the R1DO (Trapp).

On August 13, 2007 at 14:20 (EDT), the Susquehanna Control Room was notified that during review of calculations for the Secondary Containment Radiation Monitor Setpoints errors were identified in Tech Spec Allowable Values and TRM Trip Setpoints that rendered them non-conservative. The affected instruments are Refuel Floor Wall, Refuel Floor High, and Railroad Access radiation monitors. The condition affects both Susquehanna Units. The radiation monitors are required to be operable for conditions noted in footnotes (a), (b), and (c) in Tech Spec tables 3.3.6.2-1 and 3.3.7.1-1 (i.e. operations with a potential for draining the reactor vessel, during CORE ALTERATIONS and during movement of irradiated fuel assemblies in the secondary containment, and movement of irradiated fuel assemblies within or above the Railroad Access Shaft). The function of these instruments is to initiate systems that limit fission product release during and following certain postulated accidents and to minimize the consequences of radioactive material in the control room environment. The radiation monitoring instruments were declared inoperable. All movement of irradiate fuel assemblies was halted (dry fuel storage activities were in progress at the time of notification). Based on this action, these monitors are no longer within the specified Applicability, and are therefore not currently required to be operable. The event has been determined to be reportable within 8 hours under 10 CFR 50.72(b)(3)(v)(C) and 10 CFR 50.72(b)(3)(v)(D). The licensee notified the NRC Resident Inspector.

• * * UPDATE FROM G. ROBINSON TO J. KNOKE AT 1222 EDT ON 10/03/07 * * *

On August 13, 2007 PPL Susquehanna reported that during a review of calculations for the Secondary Containment Radiation Monitor Setpoints, errors were identified in Tech Spec Allowable Values and TRM Trip Setpoints that rendered them non-conservative. The affected monitors were declared inoperable and the required LCO & TRO Actions entered. A subsequent engineering review determined that the values used to establish the Tech Spec Allowable Values and TRM Trip Setpoints were based on a Realistic Source Term, not a Design Basis Source Term. These values were sufficiently conservative to compensate for the errors in the calculations and the dose release limits from a Design Basis Accident would not have been challenged. It was concluded that the existing Tech Spec values and setpoints remained valid and the monitors were operable in their original condition. Based on this conclusion Event Notification EN# 43563 is being retracted. The licensee notified the NRC Resident Inspector. R1DO ( Powell) was notified.

The following information was provided by the licensee via facsimile (licensee text in quotes): At 1500, on March 6, 2005, the Control Room declared both required divisions for three functions (Primary Containment Pressure, Primary Containment Hydrogen and Oxygen Analyzer, and Drywell Atmosphere Temperature) of Post Accident Monitoring Instrumentation (a Safety System) inoperable. The control room was notified of 'Non Quality' (non-Q) parts installed in both required divisions of a Post Accident Monitoring Instrumentation Recorder. The appropriate LCO Conditions were entered for one or more functions with two required channels inoperable. This equipment has passed all surveillance requirements and has been functional since installation. Plans are being developed to replace the non-qualified parts. This is being reported as an event or condition that could have prevented fulfillment of a safety function required to mitigate the consequences of an accident in accordance with 10CFR50.72(b)(3)(v)(D). The licensee notified the NRC Resident Inspector.

• * * UPDATE ON 03/30/05 @ 1128 BY JIM HUFFORD TO CHAUNCEY GOULD * * * RETRACTION

The following information was provided by the licensee via facsimile (licensee text in quotes): On March 6, 2005, PPL Susquehanna, LLC reported a perceived loss of safety function for three functions of Post Accident Monitoring Instrumentation on Unit 1. The notification was made pursuant to the reporting requirements of 10CFR50,72(b)(3)(v)(d). Engineering analysis has subsequently determined that the use of non-Q fuse holders in the Quality application did not adversely affect the safety-related functions which they supported. The fuse holders were removed, subjected to testing, and determined to be electrically and functionally equivalent 'to Quality fuse holders maintained at the station. This analysis conclusion provides the basis for retraction of the ENS report of March 6. The NRC Resident Inspector was notified. The Reg 1 RDO (Jim Trapp) was informed.

At 1040 hrs during setup for Unit 1 Division 1 LOCA/LOOP Surveillance testing, the controlling procedure required making the Loss of Power instrumentation for the 1A and 1C ESS buses inoperable. The specification has a 1 hour time limit for restoration, or the associated Diesel Generators must be declared inoperable. Due to delays during the setup of equipment the time requirements were not met, and the 'E' (Substituting for 'A') and 'C' Diesel Generators were declared inoperable at 1140 hrs. The Loss of Power instruments were restored, and the Diesel Generators declared operable at 1206 hrs. Unit 1 is in Mode 5 requiring only 2 diesel generators operable, therefore not impacted by the Loss of Power instrumentation inoperability. Also during the surveillance, two pump start timers failed to meet the required acceptance criteria. The 'A' ESW Pump timer actuated at 47.86 seconds (criteria; 36 sec. to 44 sec) and the 'C' ESW Pump timer actuated at 50.38 seconds (criteria: 39.6 sec. to 48.4 sec). With failure of the timers, proper loading on the Diesel Generators is not assured, and they were declared inoperable until the associated pump control breakers were opened. The 'E' Diesel Generator was declared inoperable at 1448 hrs, when the data analysis identified that the 'A' ESW pump timer did not meet acceptance criteria. The 'E' Diesel Generator was returned to operable at 1453 hrs when the DC Knife switches for the 'A' ESW pump were open. The 'C' Diesel Generator was declared inoperable at 1524 hrs, when the data analysis identified that the 'C' ESW pump timer did not meet acceptance criteria. The 'C' Diesel Generator was restored to operable at 1706 hrs after supported systems were realigned to prevent further loss of safety function and the DC Knife switches for the 'C' ESW pump were open. The Susquehanna safety analysis requires three operable Diesel Generators to safely shutdown the plant. Therefore with only two operable Diesel Generators, the condition requires an 8 hr ENS notification in accordance with 10CFR50.72(b)(3)(v)and (vi). All times referenced above are EDT. The licensee informed the NRC Resident Inspector.

* * * RETRACTION FROM R. FRY TO M. RIPLEY 1419 ET ON 05/27/04 * * * *

The following is a retraction of ENS Notification #40642 AND #40646: On April 5, 2004, PPL Susquehanna, LLC reported three events to the NRC associated with Unit 1 Division 1 LOCA/LOOP surveillance testing. In each case, the safety function of two (out of 4) emergency diesel generators was brought into question during the testing. In two of these events, the E (substituting for A) and C diesel generators were administratively declared inoperable per Technical Specifications. This was necessary because Loss of Power instrumentation for the 1A and 1C buses, rendered inoperable in support of the test procedure, was not restored within 1 hour. In the third event, the E (for A) and C emergency diesel generators were, again, declared inoperable when two ESW pump start timers failed to meet acceptance criteria thus bringing the proper start sequencing of emergency loads into question. Because the Susquehanna Safety Analysis requires three diesel generators to safely shutdown an operating unit, the potential compromise of the diesel generator safety function was a concern for Unit 2 in each instance. (NOTE: Unit 1 was in Refueling Mode 5 and was, therefore, not impacted by these events.) Accordingly, Control Room personnel conservatively initiated ENS reporting under 10CFR50.72(b)(3)(v) in response to the apparent loss of safety function for Unit 2. Subsequent engineering analysis has concluded that, although the declaration of diesel generator inoperability was correct and in accordance with Technical Specifications, fulfillment of these administrative actions did not result in an actual loss of safety function during any of the above described events. Details of the analysis show that the diesel generators were available to supply emergency power to the ESS buses and/or that sufficient redundant equipment was available to fulfill the safety function needs of Unit 2. These analysis conclusions provide the basis for retraction of the ENS reports made on April 5, 2004." The licensee notified the NRC Resident Inspector. Notified R1DO (R. Conte)

At 09:30 EDT, Unit 1 was performing the HPCI Quarterly Flow verification surveillance. Shortly after the initiation of the system an abnormally loud bang was heard. System flow of approximately 5200 gpm and discharge pressure of approximately 1300 psi was achieved at approximately 09:33. Approximately 4 seconds after reaching rated system flow HPCI discharge pressure increased to approximately 1675 psi and system flow dropped to approximately 2700 gpm. HPCI had been declared inoperable at 08:35 EDT to perform the surveillance and will remain inoperable until the cause of the loss of system flow is corrected. Because HPCI is a single train ECCS (Emergency Core Cooling System) safety system, this event results in the loss of an entire safety function which requires an 8 hour ENS notification in accordance with 10CFR50.72(b)(3)(v) and the guidance provided under NUREG-1022, rev. 2. There are no other ECCS systems presently out of service. Reactor Core Isolation Cooling (RCIC) is fully operable and HPCI entered Tech Spec 3.5.1 (14 day Limiting Condition of Operation). All other ECCS systems are fully operable. The NRC Resident Inspector was notified of this event by the licensee.

• * * RETRACTION FROM WALSH TO CROUCH ON 10/02/03 @ 1548 EDT* * *

On 09/05/2003, PPL Susquehanna LLC made an ENS notification per 10CFR50.72(b)(3)(v) in response to an apparent loss of the HPCI (High Pressure Coolant Injection) safety function. In the event, results of HPCI Quarterly Flow Surveillance testing did not meet acceptance criteria established for the system. Investigation into the cause of the failed HPCI surveillance revealed a 360-degree weld crack on the HPCI Test Line to Condensate Storage Tank (CST) Valve, HV155F008. HV155F008 is not in the reactor vessel injection flowpath. The impact of this crack, which was located between the valve seat cage assembly and the valve body, was that the HPCI Test Line to CST valve was not capable of throttling over the full range of HPCI system flows. Valve performance became erratic at higher flows because the valve seat cage was lifted out of the valve body into the flow path, increasing system resistance, and preventing attainment of design flow in the HPCI test loop. While the ability to effectively test the HPCI system using the test return path to the CST was compromised, the HPCI injection flowpath to the reactor vessel was not adversely affected by the damaged valve. Accordingly, the HPCI system maintained full capability for providing sufficient coolant to the reactor vessel in the event of a small break loss-of-coolant accident. Because the HPCI safety function was not compromised by the identified test path obstruction, this ENS notification is being retracted. The Licensee has notified the NRC Resident Inspector. Notified R1DO (Cobey).