IR 05000313/1996007
| ML20135E987 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 12/10/1996 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML20135E986 | List: |
| References | |
| 50-313-96-07, 50-313-96-7, 50-368-96-07, 50-368-96-7, NUDOCS 9612120292 | |
| Download: ML20135E987 (19) | |
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ENCLOSURE i !
l U.S. NUCLEAR REGULATORY COMMISSION l RF.GION IV l'
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l Docket Nos.: 50 313 )
50-368
!~ License Nos.: DPR-51 l NPF-6 Report No.: 50-313/96-07 i 50-368/96-07
Licensee: Entergy Operations, In Facility: Arkansas Nuclear One, Units 1 and 2 l Location: Junction of Hwy. 64W and Hwy. 333 South l Russellville, Arkansas Dates: September 29 through November 9,1996
Inspectors: K. Kennedy, Senior Resident inspector J. Melfi, Resident inspector
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4 Approved By: Elmo E. Collins, Chief, Project Branch C 1 J Division of Reactor Projects i
! I i ATTACHMENT: Supplemental Information i
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! SUMMARY Arkansas Nuclear One, Units 1 and 2 NRC inspection Report 50-313/96-07:50-368/96-07 Operations
e The performance of the Unit 1 operators and reactor engineers during the approach ;
to criticality was excellent. Support provided to the operators by reactor engineers j during the startup was very good (Section 01.2). l e The inspectors concluded that the licensee's closeout inspection of the Unit 1 reactor building was thorough and that the building was clean, with one exceptio l The inspectors identified a lack of cleanliness in the area around the rmtor coolant l system high point vents, which the licensee promptly corrected (Secoun 01.3). !
Maintenance e The licensee appropriately identified and corrected the cause of binding of the newly installed Unit 1 atmospheric dump valves (Section M1.1). )
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Enaineering e The licensee correctly determined that the emergency feedwater initiation and control anomaly originally identified at another plant existed on Unit 1 and
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conducted a thorough review of the anomaly to determine the effect on system !
operation (Section E1.1).
e The licensee's actions to identify the scope of the application of the incorrect fasteners and evaluate the effect on motor-operated valve operability were l appropriate (Section E1.2).
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e The licensee's actions in response to the identification of fuel assembly grid strap damage on Unit 1 was appropriate. The licensee repaired the grid strap damage on some fuel assemblies and determined that the structuralintegrity for those not ;
repaired was satisfactory. The licensee also discovered that the overload and '
underload setpoints for the unit refueling mast and spent fuel pool crane were set incorrectly and were nonconservative. This item is unresolved pending NRC inspection of the licensee's root cause evaluation and corrective actions (Section E2.1).
e Zebra mussels in the intake structure adversely affected the ability of the sluice gates to seal and resulted in actualleakage exceeding the calculation assumptions for emergency cooling pond inventory loss. However, the licensee determined that cycling the sluice gates would reduce leakage and that they would have approximately 2 days to implement the action. The inspectors concluded that these actions were reasonable to address the affects of the zebra mussels on sluice gate leakage. Service water system design flow rates were maintained with the observed quantity of zebra mussel shells. The licensee's plans to conduct further
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-2-inspections of the service water bays and evaluating additional actions to reduce the affects of zebra mussels were appropriate (Section E8.2).
Plant Support
- The inspectors found that the planned modifications to Reactor Coolant Pump (RCP) P-32B did not address the oil cooler piping joints and the oil fill line. In addition, weaknesses were identified after the modifications were completed in that portions of high pressure piping were not adequately protected to minimize the impact of leaks. The licensee corrected these deficiencies (Section F1.1).
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Report Details Summarv of Plant Status At the beginning of the inspection period, Unit 1 was in Refueling Outage 1R13. Operators brought the reactor critical on October 24,1996, and placed the main generator on the grid on October 25, ending the refueling outage. Unit 1 reached 100 percent power on October 28, where it remained throughout the inspection perio At the beginning of the inspection period, Unit 2 was operating at 98 percent powe Power was reduced to approximately 70 percent on November 2,1996, to repair a tube leak in the main condenser. Following completion of the repairs, power was raised to 98 percent on November 3 and remained there throughout the inspection perio . Operations 01 Conduct of Operations 01.1 General Comments (71707)
The inspectors reviewed ongoing plant operations. In general, the conduct of operations was professional and safety conscious; specific events and noteworthy observations are detailed belo .2 Unit 1 - Acoroach to Criticality Inspection Scope (71707)
Inspectors observed the Unit 1 reactor startup which was conducted on October 23 and 24,199 Observations and Findinos Unit 1 operators withdrew control rods to bring the reactor critical as part of the plant startup following completion of maintenance activities associated with Refueling Outage 1R13. Prior to commencing the approach to criticality, the Unit 1 shift superintendent conducted a crew briefing to discuss the activity. The inspectors found the brief to be comprehensive. Items discussed included procedural precautions and limitations, the estimated critical position of the rods, expected indications and plant response during the withdrawal of rods, and actions j to be taken if plant response was not as expected. This activity was conducted in accordance with the following procedures: ,
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- Procedure 1102.008, Revision 15, " Approach to Criticality"
- Procedure 1302.020, Revision 5, " Reload Criticality and Low Power Physics Test" I
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-2-The approach to criticality was very deliberate and well controlled. After ensuring that the boron concentration between the reactor coolant system and the pressurizer had been equalized, the operators commenced withdrawing rod Operators and reactor engineers in the control room exhibited excellent attention to the withdrawal of control rods and the monitoring of source range levels. The use of procedures and the quality of communications was also very goo As a result of a higher concentration of boron in the reactor coolant system than originally planned, criticality was not achieved with all of the control rods withdrawn. The reactor engineers in the control room calculated the required dilution necessary to achieve criticality and provided this information to the operators. After the calculated dilution was achieved, the reactor went critical at 3:10 a.m. on October 2 , Conclusions !
The performance of the Unit 1 operators and reactor engineers during the approach
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to criticality was excellent. Support provided to the operators by reactor engineers during the startup was very goo .3 Unit 1 - Reactor Buildina Closcout ) Inspection Scope (71707)
Prior to the reactor coolant system heatup conducted on October 17,1996, the l inspectors toured the Unit 1 reactor bui: ding to assess the quality of the licensee's '
closecut inspection in identifying and removing trash, debris, or foreign materials l which could obstruct containment sump screens in the event of a loss of coolant '
accident. The inspectors also conducted a tour following the completion of modifications to the RCP oil collection syste Observations and Findinas The inspectors found that the reactor building was generally clean and free of debris. The inspectors found some small pieces of duct tape and three tie wraps which were not previously identified. The licensee removed these item After modifications were completed on the reactor coolant pump (RCP) oil collection system (see Section F1.1), the inspectors conducted another tour of the buildin The containment was generally very clean: however, the inspectors noted grout on and in the area around the reactor coolant system (RCS) high point vents. The licensee stated that the grout was from drilling activities on the concrete missile ,
shields in the area above the high point vents during Refueling Outage 1R13. The {
grout was removed from these vents and did not affect the operability of the high
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point vent. The inspectors concluded that this should have been identified during the licensee's tours of the reactor buildin !
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1 Conclusions
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i The inspectors concluded that the licensee's closecut inspection of the Unit 1 reactor building was thorough, with one exception. The inspectors identified a lack a of cleanliness in the area around the RCS high point vents which the licensee
- promptly corrected.
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08 Miscellaneous Operations issues (92700,92901)
0 (Closed) Violation 50-368/9502-01." Failure to Properly Control the Drainina of the i Reactor Coolant System" '
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The inspectors verified the corrective actions described in the licensee's response i letter, dated April 14,1995, to be reasonable and complete. No similar problems
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[ 08.2 (Closed) Licensee Event Report (LER) 50-368/95002," Automatic Reactor Trio on
{ Steam Generator B Hiah Level as a Result of Human Error involvina Use of Imoroner
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Work Surface by a Contract Painter"
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l This event was discussed in NRC Inspection Report 50-313/95-07:50-368/95-07 dated October 30,1995. No new issues were revealed by the LE . Maintenance M1 Conduct of Maintenance
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- M 1.1 Bindina of Unit 1 Atmospheric Dumo Valve (ADV)
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j Insoection Scope (62707,92902)
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During the postmodification stroke testing of newly installed Unit 1 ADVs, the licensee identified that the valves showed signs of binding. The inspectors
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reviewed the causes for this binding and the licensee's corrective actions.
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Package 95-1015 during Refueling Outage 1R13. These valves have two sets of packing, one between the valve stem and bonnet and one between the valve plug and the plug cage. The licensee determined that the cause of the binding was cocked packing due to improper compression, which increased the force on the j valve stem.
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why the ADV was binding. The licensee did not find any damaged components
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-4-within the valve but reassembled the valve and lubricated the packing. The valve stroked satisfactorily during cold tests after the ADV was reassembled and stroked satisfactorily during hot test The licensee also noted some valve stem binding on ADV CV-2668 during the stroke tests. The initial movements were smooth but became rough during subsequent valve strokes. The licensee found that the stem-to-bonnet packing was not compressed to the vendor recommended values. The licensee compressed this packing to the vendor recommended values and the valve stroked smoothly with no binding. The licensee postulated that the packing was cocked at the lower j compression values and became uncocked at the higher compression value ] Conclusions i
The licensee appropriately identified and corrected the cause of binding of the newly installed Unit 1 ADV M 1.2 GeneraLCcmments on Surveillance Activities l Inspecdon Scope (61726) l The inspectors observed all or portions of the following surveillance activities:
e Procedure 1309.016, Revision 1, " Decay Heat Cooler Thermal Test"
- Procedure 1305.006, Revision 15, " Integrated ES System Test;"
Attachment 2, "ES Even Channels;" and Attachment 6, "ES Even Channels Corit ol Logic Check" Observations and Findinas The inspectors found the work performed under these activities to be professional and thorough. The use of job orders and procedures were appropriate and technicians were experienced and knowledgeable of their assigned task M8 Miscellaneous Maintenance issues (92700,92902)
M 8.1 (Closed) LER 50-313/96-007." Reactor Trio and Emeraency Feedwater (EFW)
System Actuation Followina De-Eneraization of Two Reactor Coolant Pumos" This event was discussed in NRC Inspection Report 50-313/96-06:50-368/96-0 The inspectors reviewed the licensee's description of the root cause of the event and the proposed corrective actions and found them to be appropriat . - _ - . - . - - . - . . - _ - - _ _ - - - . _ - - . - - . . . _ - - - . - .
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M8.2 (Closed) Deviation 50-368/9504-01." Failure of Smoke Detectors ** I
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- The inspectors verified the corrective actions described in the licensee's response ;
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letter, dated July 20,1995, to be reasonable and complete. No similar problems l j were identifie I i
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E Unit 1 - Emeraency Feedwater initiation and Control (EFIC) Anomalv I i i Insoection Scooe (92903) *
- i j On October 8,1996, the licensee identified that an anomaly existed in the .
compensation modules for the EFIC system which could affect the ability of EFIC to
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automatically control steam generator level. Condition Report 1-96-0512 was written to document this condition. The inspectors evaluated the condition and
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i reviewed the licensee's operability determinatio ;
j Observations and Findinas !
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j Based on a condition first identified at another facility, ANO identified a potential !
i problem with the EFIC control circuitry. The EFIC system provides, among other ;
- functions, the initiation of EFW, the control of EFW flow rate to the steam i generators to control level at the appropriate setpoints, and steam generator level
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rate control when required. At a steam generator level of 130 inches, the signal input to the automatic level control function switches from a low range signal to a
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high range signal. The licensee determined that an unoesired switching i characteristic of an EFIC compensation module at the 130-inch switchover point
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i generator level control and fill rate limit functions of EFIC and would not effect EFW
} initiation, the selection of the intact steam generator for feeding, the control of the
! ADVs, or the isolation of the main steam and main feedwater lines of a j depressurized steam generator.
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The inspectors reviewed the Unit 1 Technical Specifications and found that they did not address the automatic level control or feed rate functions of EFIC. The licensee i indicated that the performance of the EFIC automatic level control and fill rate limit l j was not an input to any safety analysis. As a result, the licensee determined that I
] these features were not safety-related functions and not required to establish the j operability of EFW trains or EFIC EFW initiation channels. The inspectors reviewed
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-6-the Unit 1 cmergency operating procedures and found that they provided guidance to the operators for monitoring steam generator levels and provided steps to manually control EFW flow to establish the desired level At the end of the inspection period, the licensee was formulating plans for the modification of the EFIC compensation modules to correct this potential problem, Conclusions The inspectors concluded that the licensee conducted a thorough review of the anomaly to determine the effect on system operatio E1.2 Motor-Operated Valve Fastener Discrepancies Inspection Scope (92903)
During this inspection period, the licensee performed a walkdown of motor-operated valvo actuators on both units and determined that a number of bolts used on these actuators were not the same grade as that specified by the vendor. Specifically, the bolt head markings were not the standard marking for Grade 5 bolts. The licensee performed this walkdown in response to a similar issue identified at the Waterford Steam Electric Station, Unit The inspectors performed a walkdown of a sample of safety-related, motor-operated valves; reviewed the results of the licensee's walkdowns; and reviewed the licensee's operability determinations for the affected valve Observations and Findinas The inspectors found that the licensee appror / responded to the identification of improper fasteners on safety-related, motor .serated valves by performing a complete walkdown of all accessible valves on Units 1 and 2. The licensee determined that the maximum load on the affected valves was on the actuator upper housing and, thus, these bolts were the most limiting connections. The licensee also determined that the valves whose maximum thrust ratings had previously been analyzed and upgraded were the most limiting valve The licensee performed a walkdown of all accessible safety-related, motor-operated valves in Units 1 and 2. Since Unit 1 was shutdown for Refueling Outage 1R13, all of the safety-related valves were inspected. Of the 101 valves which were inspected,39 valves had bolts which did not have the bolt head markings characteristic of a Grade 5 bolt. Since Unit 2 was at power, valves inside containment were not inspected. Of the 56 accessible valves which were inspected,23 valves had upper housing bolts which did not appear to be Grade 5 bolts. The licensee planned to inspect the remainder of the Unit 2 valves during Refueling Outage 2R12 scheduled to begin in April 199 _ - - - _ __ __ _ _ _ _ _ _
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- -7-Laboratory analysis of a sample of bolts revealed that the bolts were not Grade 5 but had a strength that was greater than Grade 2. Using this information, the licensee performed an operability determination assuming that all of the bolts on the upper housing for each motor-operated valve were Grade 2. The engineering evaluation determined that, although their was a reduction of margin, all valves remained operable. For valves that were accessible, the licensee replaced the
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substandard bolts used on the upper housing for those valves with the highest load and lowest margin and were developing plans to replace all of the substandard bolt The inspectors performed a walkdown of a sample of motor-operated valves and d
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confirmed that bolts which did not have standard Grade 5 markings on the bolt
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head were installed. The inspectors reviewed the licensee's operability evaluation, which compared the total thrust developed by each of the valves to the load bearing capability of Grade 2 bolts. The inspectors found that the licensee performed a thorough operability evaluation and appropriately bounded the worst case conditio The licensee determined that incorrect fasteners were supplied as original equipment by the motor-operated valve vendor. The licensee did not find any evidence that l the fasteners had been installed by licensee personnel and indicated that tl4cy issue i
fasteners for specific applications and do not have an "open bin" policy for the j issuance of fastener E1.3 Conclusions The inspectors concluded that the licensee's actions to identify the scope of the application of the incorrect fasteners and evaluate the effect on motor-operated
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E2 Engineering Support of Facilities and Equipment
. E Unit 1 - Fuel Bundle Damaae Identified in Refuelina Outaae 1R13 a
- . Inspection Scoce (92902)
During Refueling Outage 1R13 fuel movement, the licensee noticed several abnormalities on different fuel assemblies, including a fuel pin with a circumferential
, crack, fuel assembly grid strap tears, and movement of a fuel grid strap. The inspectors assessed the safety significance of the as-found conditions and the licensee's corrective actions related to these conditions, Observations and Findinas During the previous cycle, the licensee had indications of fuel pin leaks from a new assembly. During refueling, the licensee determined that one pin had a full circumferential crack where the pin end cap was welded on a fuel pin. The
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inspectors reviewed video pictures of the failure, which revealed that the crack was circumferential and separated. The inspectors also determined that it was highly unlikely that any fuel pellets dropped out of the fuel pin due to the end cap being supported by the lower end fitting directly underneath the fuel pin and the fuel rod
could not move enough to provide an opening for fuel pellets. The licensee believed this failure of the lower endcap was part of the manufacturing process and was waiting for the results of a root cause evaluation to be performed by the vendor (Framatome). The license reconstituted this assembly without the broken fuel pin and reinserted it back into the core.
The licensee concluded that the majority of damage to the grid straps was located at the grid strap corners. The licensee had previously discovered that the fuel
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upender did not rotate fuel assemblies to the fully vertical position. This problem was corrected following the completion of Refueling Outage 1R12. The licensee believed that, since the upender did not rotate the fuel assembly to a fully vertical position during fuel movement in previous outages, grid strap damage occurred when the fuel was lifted from the upender into the vertical mast.
- The licensee assessed the damage from the grid straps and the damaged fuel pi The assembly with the damaged fuel pin was recaged into a new assembly; other assemblies were recaged, but most of the grid strap damage was acceptable to use as is. The licensee's evaluation showed that core performance would not be l
adversely affected by the gridstraps which were not repaired, and the structural integrity of the assemblies was satisfactory. The inspectors discussed the safety significance of these items with the licensee and agreed with their conclusio The licensee identified two fuel assemblies which had grid strap damage not caused by the problem with the upender. Specifically, a once burned fuel assembly had a torn grid strap approximately five pins in from the corner and another assembly had one grid strap moved down from its normal position by approximately 12 inche Since the licensee did not identify the cause for these failures, the licensee planned to verify the alignmerit of equipment used in the entire fuel movement proces As part of the licensee's review of the damaged grid straps, they verified that the underload and overload setpoints on the spent fuel pool (SFP) crane and the refueling mast were properly set. The licensee found that the setpoints were in accordance with the fuel assembly vendor's original recommendation. However, because the licensee had previously changed the grid strap material from inconel to zircaloy, these setpoints were incorrect and nonconservativ The licensee determined that the underload setpoint was set approximately 15 pounds nonconservatively. The licensee reset the underload setpoint on the Unit 1 refueling mast and SFP bridge crane to the correct values prior to the core reload. The inspectors verified that the setpoints on the Unit 1 SFP bridge crane were set to the new values. The licensee was assessing the setpoints on both unit .__ - m. .. _._ _ _ _ -. _ _ _. . _._.. _ ..~.___ _ __ _ _ ___ _ _ _
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Further inspection is planned to review the root cause evaluation for the fuel pin failure and the incorrect crane setpoints and to assess the underload and overload setpoints for the Unit 1 refueling mast and fuel movement cranes used on Unit 2 (Unresolved item 50-313/9607-01:50-368/9607-01). Conclusions The inspectors concluded that the licensee's actions in response to the identification of a cracked fuel pin and fuel assembly grid strap damage on Unit 1 were appropriate. The licensee repaired the grid strap damage on some fuel assemblies and determined that the structural integrity for those not repaired was satisfactor The licensee also discovered that the overload and underload setpoints for the unit refueling mast and SFP crane were set incorrectly and were nonconservativ Further inspection is planned to follow up on the licensee's root cause evaluation and corrective action E8 Miscellaneous Engineering issues (92902,92903)
E (Closed) Violation 50-313/9406-01," Failure to Write a Condition Report for Drawina Errors" The inspectors verified the corrective actions described in the licensee's response letter, dated September 29,1994, to be reasonable and complete. No similar i
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problems were identified.
E8.2 (Closed) Unresolved Itern (URll 50-313/9606-03."Hiah dP Across SW Pumo Strainers" Inspection Scope (92902)
NRC Inspection Report 50-313/96-06: 50-368/96-06 documented the licensee's discovery of a significant number of zebra mussels in the Unit 1 intake structure, which adversely affected the operation of the sluice gates and clogged the service water (SW) discharge strainers. The accumulation of zebra mussels on the sluice gates resulted in the leakage past the sluice gates, which separate the SW bays from Lake Dardanelle to limit leakage from the ECP in the event of a loss of the lake, to be higher than calculation assumption This issue remained unresolved pending completion of the foilowing items:
- An assessment of the SW system past operability due to the leakage from
! the sluice gate * An assessment of the effects of zebra mussels on the SW discharge
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growt I Observations and Findinas j
For both units, the design basis for the ECP inventory is to supply one unit to cold shutdown while the other unit has a loss-of-coolant accident, coincident with a loss of the lake as a suction source. Included in this inventory are assumptions for sluice gate leakage from the SW bays back into the lake and leakage for valves which are the interface of nonsafety-related systems with SW. The Final Safety l Analysis Report values are for 75 gpm of total leakage based on an engineering I calculation of 89 gpm. The calculation assumption is that this 89 gpm leak rate occurs over a 30-day period following a loss of Lake Dardenelle without operator actio The licensee found that leakage past the Unit 1 sluice gates was 144.1 gpm and l the boundary valve leakage was approximately 9.7 gpm. On Unit 2, the total '
leakage, including sluice gate and boundary valve leakage, was 2.8 gpm. Thus, the <
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total as-found leakage from both units was 156.6 gpm, greater than the 89 gpm '
used in the calculatio The licensee determined that, without operator action, the as-found leakage would j have compromised the capability of the SW system to supply water for the I assumed 30-day period. The licensee demonstrated that operator action could be taken to compensate for the leakage. For example, by raising a sluice gate for several minutes, the licensee found that the sluice gate sealing surfaces cleared sufficiently to reduce leakage below the assumed amounts when the sluice gate was subsequently closed in addition, the licensee calculated that they would have
over 2 days to take action to reduce leakage from the sluice gates. The inspectors reviewed their calculation and found that it was conservativ The inspectors assessed the possibility of the debris in the SW bays increasing the SW discharge strainer's differential pressure and then reducing the SW flow rate.
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either cleaning the strainers or by stopping the affected SW pump and restarting the pump after the pump stopped rotating. The licensee also calculated that they could
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have a higher strainer differential pressure than observed and still maintain required SW design flow rates. The inspectors concluded that the possibility affecting both SW flow trains simultaneously was remote and the licensee could rapidly reduce strainer differential pressure in an emergenc To address this issue, the licensee cleaned the SW bays and the areas in the intake structure that could affect the SW bays. The licensee also removed sand, silt, and other deoris in front of the intake structure to limit the effccts of debris and biological growth on the SW bays. In addition, the licensee is taking continuing actions to minimize the affect of the zebra mussels. These include inspection of the
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SW bays with divers and draining to clean affected portions of the intake structure if necessary. The licensee is also evaluating other modifications to the SW structure to reduce the effect of zebra mussels; including coatings, continuous cleaning, and structural barrier Conclusions The inspectors concluded that zebra mussels in the intake structure adversely affected the ability of the sluice gates to seal and resulted in actualleakage exceeding the calculation assumptions for ECP inventory loss. However, the licensee determined that cycling the sluice gates would reduce leakage and that I they would have greater than 2 days to implement the action. The inspectors concluded that these actions were reasonable to address the affects of the zebra mussels on sluice gate leakage. The inspector further concluded that service water system design flow rates were maintained with the observed quantity of zebra mussel shell E8.3 (Closed) LER 50-313/96-008:50-368/96-008." Sluice Gate Leakaae Resulted in I Inability to Maintain ECP Inventory for 30 Davs" This event is discussed in Section E8.1 of this report and in NRC Inspection Report 50-313/96-06:50-368/96-06. No new issues were revealed by the LE IV. Plant Support F1 Control of Fire Protection Activities F Unit 1 - Walkdown of the RCP Lift Oil Systems Followina Fire in the Reactor Buildina i Insoection Scone (93702)
On October 17,1996, Unit 1 experienced a fire in the reactor building while heating up the RCS. The source of the fire was oil soaked insulation on Steam Generator E-248. The fire was quickly identified and extinguished by the license The fire did not result in any significant damage. The licensee determined that the source of the oil was a cracked weld in the discharge piping of Lift Oil Pump P-80B associated with RCP P-32B. During the performance of a postmaintenance test on October 9,1996, maintenance workers identified an oil mist in the vicinity of the lift oil pump and determined that the source was a cracked weld on the discharge piping of Lift Oil Pump P-808. The oil was wiped up and the defective weld repaired. However, the licensee did not adequately determine the extent of the oil spray and, thus, did not identify that Steam Generator E-24B had been sprayed with oi .
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l On October 18,1996, the licensee committed not to heat up the Unit 1 RCS above l 200 F until they and the NRC agreed that the Unit 1 lift oil systems were in I compliance with the requirements of 10 CFR Part 50, Appendix R, or that adequate j compensatory actions had been established (Entergy Letter 1CAN109609 dated j October 18,1996, from C. R. Hutchinson to L. J. Callan). On October 19 and 21, l the inspectors performed a walkdown of the lift oil systems and oil collection l
systems associated with each RCP to determine whether or not the configuration of I the oil collection systems complied with the requirements of 10 CFR Part 50, Appendix R. The inspectors assessed discrepancies in the oil collection systems identified by the !icensee and discussed with licensee personnel their planned modifications to correct these discrepancie A specialinspection was conducted to review this event. The results of this inspection and any enforcement issues associated with the oil collection system are addressed in NRC Inspection Report 50-313/96-27:50-368/96-2 b. Observations and Findinas The inspectors found that the configuration of the lift oil system and oil collection system on RCP P-328 was different than the configuration of the other three pumps. The motor on Pump P-328 had been replaced in Refueling Outage 1R12 (February / March 1995) with one that was different than the others. The inspectors observed that, while the lift oil system piping and pumps on RCPs P-32A,-32C, and-32D were enclosed in a shroud around the top of the motor, the lift oil piping and pumps on Pump P-32B were not enclosed in a shroud. During the inspection, the licensee described their planned modifications to Pump P-32B to install shrouds around the lift oil system. The inspectors identified additional discrepancies which appeared to be contrary to the requirements of 10 CFR Part 50, Appendix Specifically, there was no oil collection system in place for the oil fill line to the motor oil reservoir or the remote oil fill line used to add oil to the reservoir, and the collection system installed for the piping to the oil cooler did not appear to be adequat During the walkdown of RCPs P-32A,-32C, and -32D, the licensee discussed the oil collection discrepancies they had identified as a result of their previous walkdown and described their planned corrective actions. The discrepancies involved oil collection pans that did not extend far enough to collect potential leakage from some low pressure oil lines and instruments. The inspectors identified an additional concern with an instrumentation cable that was routed from underneath the shroud and over the edge of the oil collection tray such that oil leakage in the shroud could collect on the cable and flow down the cable past the oil collection pa On October 21, the inspectors conducted a walkdown of the Unit 1 RCP lift oil and oil collection systems to inspect the modifications that the licensee had made to all four RCPs. The inspectors found that the licensee had modified the oil collection
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e i-13-i systems on RCPs P-32A, -32C, and -32D to extend the collection pans and to '
address the inspectors' concerns regarding the instrumentation cables. However, ,
the inspectors found that the modifications made to RCP P-328 were not adequate in that some high pressure lift oil system piping remained unprotected and other ;
mechanical joints were not adequately covered to collect spray. The licensee I subsequently made the necessary modifications to the RCP P-32B oil collection system to address the inspectors' concern The licensee did not make any modifications to provide oil collection devices for the remote oil fill lines. Instead, the licensee implemented compensatory actions to restrict the use of the remote filllines until further evaluations for corrective actions were completed, c. Conclusions The inspectors found that the planned modifications to RCP P-32B were limited in scope in that they did not address the oil cooler piping joints and the oil fill line, in addition, weaknesses were identified after the modifications were completed in that portions of high pressure piping were not adequately protected to minimize the impact of leaks. The licensee adequately addressed these deficiencie I
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O ATTACHMENT SilPPLEMENTAL INFORMATION l
l PARTIAL LIST OF PERSONS CONTACTED l l
Licensee !
C. Anderson, Unit 2 Plant Manager M. Cooper, Licensing Specialist D. Denton, Support Director M. Harris, Unit 2 Maintenance Manager i
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R. Lane, Director, Design Engineering M. Little, Unit 1 Operations L. Schwartz, Supervisor, Unit 2 System Engineering M. Smith, Supervisor, Licensing i A. South, Licensing l R. Starkey, Unit 1 System Engineering Manager !
J. Veglia, Modifications H. Williams, Jr., Plant Security, Superintendent C. Zimmerman, Unit 1 Plant Manager i
NRC K. Kennedy, Senior Resident inspector J. Melfi, Resident inspector INSPECTION PROCEDURES USED 61726 Surveillance Observations 62707 Maintenance Observations 71707 Plant Operations 92700 Onsite Followup of LERs 92902 Followup - Maintenance 92903 Followup - Engineering 93702 Prompt Onsite Response to Events ITEMS OPENED, CLOSED. AND DISCUSSED Ooened 50-313/9607-01 UNR Cause of fuel pin failure, nonconservative crane setpoints, and verification of correct setpoints for both units refueling masts and SFP cranes
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-2-Closed 50-368/9502-01 VIO Failure to Properly Control the Draining of the Reactor Coolant System 50-368/95002 LER Automatic Reactor Trip on Steam Generator B High Level as a Result of Human Errot involving Use of improper Work Surface by a Contract Painter
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50-313/96-007 LER Reactor Trip and Emergency Feedwater System Actuation Following De-Energization of Two Reactor Coolant Pumps 50-368/9504-01 DEV Failure of Smoke Detectors 50-313/9606-03 URI High dP Across SW Pump Strainers i
50-313(368)/9606-008 LER Sluice Gate Leakage Resulted in inability to Maintain Emergency Cooling Pond Inventory for 30 Days 50-313/9406-01 VIO Failure to Write a Condition Report for Drawing Errors LIST OF ACRONYMS USED l
ADV atmospheric dump valve ECP emergency cooling pond EFIC emergency feedwater initiation and control EFW emergency feedwater LER licensee event report RCP reactor coolant pump RCS reactor coolant system SFP spent fuel pool SW service water UNR unresolved URI unresolved item VIO violation l
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