IR 05000369/1997010
| ML20211E470 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 09/08/1997 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML20211E448 | List: |
| References | |
| 50-369-97-10, 50-370-97-10, NUDOCS 9709300141 | |
| Download: ML20211E470 (25) | |
Text
- _ - _ - . . - . . .- . _ - . - - _ _ - . . _ . -. . - _ - . -
, ,
.
.
4
, U.S. NUCLEAR REGULATORY COMMISSION REGION 11 Docket Nos: 50-369. 50-370 License Nos: NPF-9. NPF 17 i
Report No: 50 369/97 10, 50 370/97-10 l
Licensee: Duke Power Company Facility: McGuire Generating Station. Units 1 and 2
Location: 12700 Hagers Ferry R Huntersville NC 28078
, Dates: June 29 August 9, 1997 Inspectors: M. Sykes. Acting Senior Resident Inspector M. Franovich. Resident Inspector D. Forbes. Regional Inspector (Sections R1.1 R N. Economos. Regional Inspector (Sections M1.2, M1.3)
Approved by: C. Ogle. Chief, Projects Branch 1 Division of Reactor Projects
,
\
W"\L\
- q Enclosure
[k"Soo$k000
. - - . . ..
- , - - - . - - - - - - - - - - . - . - . - - - . - - , - - - - - . - - - - . , - - - , . - - - - - - - - - - - - - - - . - - - - - - - - . , - - - , - - - - - - .- ---- - - - - - - - - - - - - - - - , - - . - - - - - - - - - - - - - - - - , - -.
.
.
.
EXECUTIVE SUMMARY McGuire Generating Station. Units 1 and 2 NRC Inspection Report 50 369/97 10, 50-370/97-10 This integrated inspection included aspects of licensee operations, engineer-ing, maintenance, and pl6at support. The report covers a six w?ek period of resident and region based inspectio Operations e In general, the conduct of operations was satisfactor (Section 01.1)
e The inspector concluded that the licensee made NPC notifications in accordance with the requirements of 10 CFR 50.72. (Section 02.1)
. The licensee's trip responso and recovery following the Unit 2 low reactor coolant flow automatic trip was good. The inspectors noted that the current progrt.m for replacement of the reactor ccolant pump motors on a rotational bcsis is acequate to improve coolant pump motor reliabilit Preventing similar failures prior to the completion of the coolant pump motor rewind program mcy be an operational challeng (Section 02.2)
Maintenance
- Routine maintenance activities observed by the inspectors were completed satisfactorily. (Section M1.1)
. The inspectors determined that the installation and testing of the subject motor was performed by )ersonnel that were adequately trained to perform their assigned tasks. )rocedures used on this activity were well written and provided adecuate direction and details to successfully complete the task. (Section Fl.2)
- A review of fabrication records and nondestructive examination results
-
disclosed that weld fabrication and associated activities were conducted in a satisfactory manner. (Section M1.3)
. Activities associated with the steam generator (S/G) replacement project were being performed by adequately trained aersonnel in a conscientious manner. Housekeeping of facilities where tle S/Gs were being stored were maintained at an a)propriate level. Material used was in compliance with applica)le code requirements. (Section M1.3)
- The licensee's repair efforts were appropriate to ensure proper performance of main feedwater isolation valve 2CF28. The valve was verified to meet stroke time requirements and operated as designed to isolate feedwater following a safety signal. (Section M2.1)
- The repair of a failed instrument line at the Unit 1 moisture se)arator reheater crossover piping was adequately planned and execute ?re-job Enclosure
l
.
ls l
l l
l l briefings emphasized personnel safety and the repair received good management oversigh (Section M2.2)
- Performance in planning cnd executing the repair of the number 3 main steam stop valve actuator stem was good. Appropriate emphasis was placed on >ersonnel safety and the licensee made prudent decisions to minimize tie probability of unplanr.Jd reactivity incidents. (Section M2.3)
l e Corrective actions for tne Unit 1A emergency diesel generator (EDG) 6L l
'
cylinder exhaust valve oil leak were prompt and effective. The root causeevaluationwasthoroughanditdidnotappearthatacommonmode failure existed. Station personnel were very Knowledgeable of the EDG syste (Section M2.4)
. The inspectors concluded that the licensee's aerformance in meeting established work management goals was goo rioritization of work activities was evident. Although no instances of missed preventive l maintenance activities were identified, some process deficiencies were
,
note (Section M3.1)
Enoineerina
.
. The licensee's decision to continue using the instrument air sup)ly for
'
nozzle dam seals prior to com)leting a Temporary Modification (Ti) was, in this case, acceptabl T1e responsible engineer's immediate and detailed investigation of system performance was indicative of a good questioning attitude. A Ncn Cited Violation was identified for the initial failure to implement the iM process. (Section E4.1)
l
. The Operating Experience Program has adequately assisted the McGuire l Nuclear Station in timely evaluation and resolution of relevant industry l 1ssues. Site specific actions to resolve specific issues have adequately sustained nuclear safety and equipment reliability. (Section l E6.1)
.
- The licensee's evaluation did not a) pear to address the validity of the l
1soto)ic gap fractions used in the Jpdated Final Safety Analysis Re) ort
'
(UFSAR) Table 15-35 for the fuel handling accident analysis for hig1 burnup fuel )rior to exceeding the burnup limit specified in Regulatory Guide 1,25 () asis for the table). Insufficient information existed to determine if the radiological consequences were acceptable for an l accident ihvolving high-burnup fuel: therefore, this issue is identified l as an Unresolved Ite (Section E7.1)
! Plant Suonort
- Radiological facility conditions and housekeeping in radioactive waste storage areas were good. Material was labeled appropriately, and areas were properly posted. All exposures were below regulatory limits and the licensee was continuing to maintain exposures As low As Reasonably Achievable. (Section R1.1)
l Enclosure
< .
.
.
e Based on a review of training activities for radiation protection technicians, the inspectors determined radiation protection technicians were receiving an appropriate level of training to accomplish the work activities observed. (Section R5.1)
.
Enclosure
_ _ _ _ _ _ _ _ _ _ . _ . _ _ _ _ . _ _ . _ _ _ _ . _ _ _ . _ _ _ _
. . ,
hpo.r.t_ Details l
l Summary of Plant Status i
Unit 1 began the period at 100 percent rated thermal ower. On July 1. a leak was identified at an instrument line on the Unit I hi h pressure turbine crossover piping to a Moisture Separator Reheater (MS ). Unit 1 output was reduced to approximately 20 percent to complete repairs. Unit I was returned to 100 percent power on July 2. On July 3. the number 3 high pressure turbine stop valve closed with the unit at 100 percent power. On July 12 power was reduced t( approximately 95 percent to realign the number 3 turbine stop valve to its norrnal position. Following restoration of full power later that da Uni' 1 operated at 100 percent for the remainder of the reporting perio Unit 2 began the period at approximately 28 percent power following an
,
unplanned shutdown to repair an approximately 70 gpd steam generator leak in the 2A steam generator. Unit 2 reached 98 percent power on July 1. Power output was limited because of reduced steam pressure from significant steam generator tube plugging. Feedwater heating steam was throttled back to q increase main turbine pressure and power output reached 100 percent. On July
'
i 11. Unit 2 automatically tripped on low reactor coolant system flow as a result of the failure of the 2D reactor coolant pump motor. While shutdow the licensee determined that 10 of 48 ice condenser inlet doors were
-
inoperable because of upward ice condenser floor movemen After repairs to 2 the failed reactor coolant pump motor and lower ice condenser inlet doors were made. Unit 2 was returned to Mode 1 on July 22. On August 4. power was reduced to approximately 95 percent to complete Moderator Temperature Coefficient measurement. Unit 2 was returned to 100 percent power on August 5 and continued to operate at 100 percent power for the retainder of the report ug period.
,
Review of Updated Final Safety Analysis Reoort (UFSAR) Commitments While performing inspections discussed in this report, the inspectors reviewed
- the applicable portions af the UFSAR that were related to the areas inspecte , The inspectors verified ; hat the UFSAR wording was consistent with the
]
observed plant practicer, procedures, and/or parameter I. Operations 01 Conduct of Operations 01.1 k neral Ccmments (71707)
Using Inspection Procedure 71707. the inspectors conducted frequent reviews of ongoing plant operations, In general, the conduct of l operations was professional and safety-conscious; specific events and !
noteworthy observations are detailed in the sections below, i
Enclosure l
!
..- . - . -.
.
.
-
.
l I
02 Operational Status of Facilities and Equipment 02.1 10 CFR 50 72 Notifications Insoection Scone (71707)
Durin9 the inspection )eriod, the licensee made the following notifications to the NRC. The inspectors reviewed the events for impact on the operational status of the facility and equipmen Observations and Findinas
- On July 11, 1997, the licensee made a report in accordance with 10 CFR 50.72 due to an automatic Unit 2 trip on low reactor coolant system flow. The low flow condition was the result of a reactor coolant pump trip due to a stator faul * On July 12. 1997, the licensee made a report in accordance with 10 CFR 50.72 due to an unplanned Unit 2 ice condenser inlet door actuation. The licensee subsequently retracted the notification after verification that the actuation was not an Engineered Safeguard Feature actuatio * On July 18. 1997, the licensee made a report in ar.cordance with 10 CFR 50.72 due 10 of 48 Unit 2 lower ice condenser doors being declared inoperable. The doors were suspected to have been inoperable during Modes 1. 2, 3. and Conclusions The inspectors concluded that the licensee reported the above events in accordance with the requirements of 10 CFR 50.7 .2 Automatic Unit 2 Reactor Trio - Low Reactor Coolant Flow Inspection Scone (93702. 40500)
On July 11. Unit 2 automatically tripped from 100 percent reactor power due to low reactor coolant flow with reactor power greater than 48 percent. The main turbine automatically tripped following the reactor tri Both motor driven auxiliary feedwater pum)s started on low low steam generator level in one steam generator. T1e 20 Reactor Coolant Pump (RCP) tripped, causing the low reactor coolant flow condition. The inspectors responded to the event, interviewed operations personnel, and evaluated equipment performanc Observations and Findinas Following the reactor tri), the licensee conducted extensive investigations of the 2D RCP motor and associated power supplie The Enclosure
. .. .. .
.
.. ..
.
______ ____________ ___ ________ __-_ _- _ _ _-__ __ _ _ _ _ _ _
,
.
RCP safety and non safety breakers tripped on overcurrent. Upon further evaluation of the power supply equipment and the coolant pump motor, the licensee noted that stator winding insulation damage was evident and a stator fault had occurred. The reactor coolant pump motor protective relaying operated as designed to separate the coolant pump from its power sourc As a result of this failure, the licensee removed the damaged stator and replaced the stator with a completely rewound spare stato The licensee previously developed a rewind / replacement program to improve RCP motor performance. The program was developed to ins)ect and rewind each of the Unit 1 and Unit 2 RCP motors on a rotational ) asi The 2D RCP motor was scheduled for replacement during the next scheduled Unit 2 outage. The licensee had the 2D motor stator refurbished by the vendor previously, following a similar failure of the 2B RCP motor stator in May 1996. At that time, the refurbishment included improving the structural support of the stator windings to reduce the rate of insulation breakdow Each stator winding end turn was also secured to the stator support rin The inspectors also reviewed the licensee post trip review report. The report identified equipment that did not operate as expected during the transient. The equipment included the A main feedwater pump speed controller, auxiliary feedwater discharge valve to the C steam generator, and the A auxiliary feed puma motor inboard bearing oil feeder. The inspectors verified that t1e equi) ment deficiencies were adequately evaluated and/or repaired prior to Jnit 2 restar c. Conclusions The inspectors concluded that the licensee's reactor trip response and recovery was good. The inspectors also concluded that, once complete the current program for replacement of the RCP motors should improve RCP motor reliabilit However, the inspectors noted that similar operational challenges may result prior to the completion of the reactor RCP motor rewind progra II. Maintenance M1 Conduct of Maintenance M1.1 General Comments a. Insoettion Stone (61726 and 62707)
The inspectors observed all or portions of the following work activities:
- PT/1/A/4350/02B 1B Emergcncy Diesel Generator (EDG)
Operability Run Monthly Enclosure
-
_ _ _ - _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
. .
.
. PT/2/A/4401/148 Unit 2 Component Cooling (KC)/ Residual Heat Removal (ND) Heat Exchanger Valve Stroke Timing
- PT/2/A/4200/288 Unit 2 Train B Slave Relay Test Observations and Findinas The inspectors witnessed selected serveillance tests to verify that approvea procedures were available anu in use, test equipment in use war calibrated, test prerequisites were met system restoration was completed, and acceptance criteria were met, in addition. resident inspectors reviewed and/or witnessed routine maintenance activities to verify, where applicable, that approved procedures were available and in use, prerequisites were met, equipment restoration was completed, and
,
maintenance results were adequat Conclusion The inspectors conclui d that these routine activities were completed satisfactoril M1.2 Installation of 1A Condensate Booster Pumo Motor Inspection Scone (62707.62700)
The inspection was performed to determine by work observation and document review the adequacy of handling, installing, and testing the subject Unit 1 moto Observation and Findinas The motor was removed from service in response to a persistent high vibration indication. At the time of the inspection, the motor had been returned from the vendor shop and the licensee was preparing to reinstall it back on the pum On August 6,1997, the ins)ectors observed the lift, instaliation, aligrment and testing of t1e motor before it was coupled to the 1A condensate booster pump. The activities observed were performed under work order 97039871-05 and in accordance with the following procedures:
- Lift Plan Task-05 7/31/97
- MP/0/A/7300/001 Re Rotating Equipment - Preventive Maintenance
. MP/0/A/7700/009 Coupling Alignment Soft Foot Check and Correction
. MP/0/A/7300/007 Rotating Ecuipment Inspection and Vibration Feasuring Enclosure
.
. .
.
.
o IP/0/A/3190/005 Inspection and Testing of Motors The inspectors found the work performed under these activities to be professional and thorough. All work observed was performed with the work package present and in active use. Technicians were experienced and knowledgeable of their assigned tasks. The inspectors frequently observed supervisors and system engineers monitoring job progres Quality control personnel were present when required by procedur Equipment used to perform required tests were properly calibrated and in good working order. Motor inspections and tests performed included:
winding resistance. insulation resistance, dielectric absorption (polarization), direct current (DC) steo voltage (hipot), and visual inspection. These tests showed the motor characteristics and performance were within acceptable limit Conclusion The inspectors determined that the installation and testing of the subject motor was performed by aersonnel that were adequstely trained to perform their assigned tasks. ?rocedures used on this activity were well written and provided adequate direction and details to successfully complete the tas M1.3 Steam Generator Reolacement (SGR) Unit 2 lupection Stone (5000 Q The inspection was performed to determin9 the adequacy of the onsite manufacturing (OSM) facilities and fabrication shop activities for the SG Observation and Findinas The inspectors toured the OSM facilities used for storage, machining, welding and nondestructive testing of the steam generators (S/Gs) before their installation. At the time of the tour. S/G status was as follows:
. S/G A Instrument nozzles were being prepared for welding a short piece of Jipe to facilitate welding inside containment, All of the scleduled work was complete . S/G B Work on the secondary side nozzles was complete Welding was in progress on instrument nozzles,
. S/G C All work scheduled on this S/G was completed. The S/G was aressurized and ready for transfer to the containment
)uildin * S/G D Welding on the secondary side nozzles was complete The S/G was ready for security check Enclosure
__ . _ . _ _ . _ _ . _ _ _ _ _ _ _ _ _ _ _ ..._ _ .
- '
4 ;
. ,
,
,
,
6 i
- - ;
- The inspector noted that access control was being maintaine *
i housekeeping was adequate, and all S/G penetrations were adequately j protected from foreign material entr Weldina of Secondary Pioina l i i Welding of dissimilar metal joints on the secondary S/G nozzles had been !
- completed. These welds had been radiogra>hed per applicable code *
'
requirements and radiographic procedure N)E 10c, Rev.19. As such, the '
inspectors reviewed the following radiographs for film and radiographic guality documentation and compliance with code requirements. ASME 3 Sections V and XI, 1989 Edition and Section III. 1971 Editio ! Held Size Remarks i i
.
1 CAZFW50 21 6"x.719" Accept i CAZFW50 28 6"x.719" Accept ,
CAZFW50 24 6"x.719" Accept
. CAZFW50 32 6"x.719" Accept i i B82FW71-33 3"x.438" Accept i BBZFW71 02 3"x.438" Accept BBZFW68 02 3"x.438" Accept l BBZFW68 37 3"x.438" Accept ;
This review revealed that the radiographs met applicable code !
j requirements and that the quality control activities were satisfactor '
! Wg1dina Activities in the Fabrication Shoo At the time of this -inspection.-production welding had not begun.
! However, technicians were performing weld preparations / machining on
! straight ipe sections and on elbows in preparation for the fabrication
- of spool ieces for use during S/G installation. For the most part.
'
this acti ity will involve the main feedwater (CF) and auxiliary
, feedwater (CA) systems and to a lesser extent, other small bore piping.
i The inspector observed weld )re)aration machining and grinding in
! progress on the CF system, w11c1 appeared to be progressing in a
- satisfactory manner. Identification numbers were noted for material
- traceability review, Preliminary plans called for the following
'
l breakdown of weld fabrication between the fabrication shop and the i- fiel *
System Fab Shoo Eield I_o.t.al *
I I CA 4 16 20
,
CF 36 22 58 ,
l The following is a list of pipe sections and fittings for which material ,
i traceability was checked for compliance with applicable code
- requirement Enclosure
,
em,-.-,-.m.,---=y .+-w--, ....,-.w----------e.,c,,.um, ,,,,,..w,,y,y,w,,y, w w e r w ~-. %, e. - w em, ---,.-,--,-,e~.--r- + ee m-ee.--ww--=--w-ev
_ ~__._ _._____ ___ __.___ _ _ .- ---. . -- -
. . ,
i
,
,
Unicue Trackina Code Material Heat # Skg i
j 845047 SA234.GR.WP11 FP10C 18"dia. Ell sch. 80
.
- 846674 SA335.GRP11 952542 18"dia sch. 80 !
j 846634 SA335.GR.P11 942558 16"dia sch. 80 851806 SA234.GRWP11 1G4B2U1F9 18"X16" Reduce sch. 80 f 846636 SA335,GRP11 76977 16"dia. sch. 80 .
846753 SA335.GRP11 195097- 18"dia. sch. 80 t .
l Information on this material was readily available and the reported i analysis along with physical test results indicated that the material .
i met minimum code requirement !
- Conclusions
.
! Results of this inspection revealed that activities associated with the i S/G replacement-project were being performed by adequately trained
! personnel in a conscientious manner. Housekeeping of facilities where f the S/Gs were being stored were mair.tained at an appropriate level, s Material used was in compliance with applicable code requirements. A review of fabrication records and nondestructive examination results disclosed that weld fabrication and associated activities were conducted ,
in a satisfactory manne H2 Maintenance and Material Condition of facilities and Equipment M2.1 Main Feedwater Isolation Valve 2CF28 Corrective Maintenance' Insoection Scooe (62707)
During the Unit 2 shutdown to repair a S/G A tube leak, the inspectors !
reviewed the licensee's repairs of the Unit 2 Steam Generator "C" Feedwater/ Containment Isolation Valve. 2CF2 Observations and Findinas A. valve stem packing leak had been identified previously by the licensee and repair efforts were attempted: however, the packing leak was not corrected. As a result, the licensee had established a monitoring program to evaluate the packing leak daily and added the repair activity to.the forced outage maintenance list. During the shutdown, the licensee was able to isolate that portion of the system and replace the degraded packin The. licensee repacked the. valve and conducted valve stroke time testing. During the testing, the valve failed to meet opening stroke time requirements. The design function of the valve is to close to isolate feedwater' flow to containment and provide a containment isolation boundar The valve packing was reworked and the Enclosure a
- - - .__ - .___ - .
. .
-
.
valve was reassembled and stroke time tested satisfactoril The valve was returned to service prior to operation at rated powe Following the repair, the licensee eliminated the leakage monitoring plan, but continues to periodically monitor valve actuator temperatures to ensure that elevated operating temperatures do not increase the probability of hydraulic fluid degradation. (See Inspection Report 50 369. 370/97 04.)
c. Conclusions The inspectors concluded that the licensee's repair efforts *. ore appropriate to ensure proper performance of valve 2CF28. The valve was verified to meet stroke time requirements and operated as designed to isolate feedwater. Issues associated with elevated actuator assembly temperatures causing operational challenges were also evaluated and determined not to be a concer M2.2 Steam Leak at Unit 2 Hioh Pressure Turbine Pioina instrument Line Insoection Scone (62707)
On July 1. the licensee identified a main steam leak at an instrument line located on the Unit 2 crossover piping from the main high pressure turbine to a moisture separator reheater, b. Observations and Findincs The licensee reduced r.awec in an effort to reduce the steam pressure at the instrument line and installed an isolation valve on the sevared line to isolate the leak. The instrument tap was used for turbine acceptance testing only and did not affect control systems. After completion of the repair, the licensee returned the unit to 100 percent power. The instrument tubing was sent to the licensee's metallurgical facility for additional metallurgical evaluation, c. Conclusions The inspectors attended pre job briefings and noted that appropriate emphasis was placed on safet Planning, execution, and management oversight of the repair activities were goo M2.3 Unit 1 Main Steam Ston Valve Actuator Stem Failure Insoection Scone (62707)
On July 5. the inspectors responded to the failure of the number 3 main steam stop valve actuator stem. The stem failure resulted in a brief increase in reactor power, to which control rods responded in automatic to maintain reactor power below thermal power limits, Enclosure w -w- v- misv+w-- w- %-,e--- -wv- ,-y+ -
---w rwwwww
-
.
. .
'
t
,
'
9 bservation u nd Findinas The licensee and inspectors immediately responded to the high pressure turbine. No obvious indication of stem failure was noted: however.
1 after careful review, the discharged actuator spring was evident. The actuator stem had failed. resulting in a fast closure of the stop valv The closure of the stop valve is not in itself a turbine trip signa Closure of all 4 stop valves or low auto stop oil pressure would have
.
resulted in a turbine trip and reactor trip at thermal power levels
greater than 48 pc.' cen The licensee developed detailed repair plans and executed the repai Adequate nuclear and personnel safety )recautions were developed and implemented. The licensee completed t1e repair and reduced reactor power prior to returning the stop valve to its normal position. The i
power reduction provided adequate reactivity margin in the event the valve went to the full open position once energized. This minimized the potential for exceeding the licensed rated thermal power output. The
-
valve was returned to service with no difficultie The licens w. aware of the potential for failure. had previously begun a replacement project to replace the actuator stems on a rotational basis during outages The licensee is evaluating the current replacement ,
schedule for the remaining actuator stems, Conclusio_n
.
The in a y b .; -'oncluded that the licensee's performance in planning and executing ine repair activity was good. Appropriate emphasis was placed on personnel safety and the licensee made prudent decisions to minimize the probability of unplanned reactivity incident M2.4 1 it 1 A Emeroency Diesel Generator (EDG) Cylinder Fluid leak a. Insoection Jcone (62707)
On July 1! 1997, the licensee identified a cylinder leak on the Unit 1 A Emergency Diesel Generator during a quarterly performance test. The inspector reviewed the circumstances related to the issue, the root cause determination. and subsequent corrective actions. Maintenance and engineering personnel were interviewed. the affected cylinder head and replacement were examined, and the potential for common-mode failure of the EDGs was evaluated, Observations and Findinas During performance of PT/1/A/4350/02A. Enclosure 13.6. Check of Diesel Generator 1A Cylinders for Fluid, the licensee discovered that the 6 left (60 cylinder was leaking fluid out of the open petcock. The purpose of the test is to examine if moisture has accumulated in the Enclosure
-
__ _ ---- - - - _ .- - .. .- . . _ _ -
. .
.
cylinder hea This periodic test (PT) was the first PT performed on the EDG since the rebuild earlier this year. The Unit 1 A and B EDG cylinder heads were rebuilt offsite by a vendor during the last Unit 1 outage as part of an overall effort to improve EDG performanc Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of discovery, the licensee replaced the 6L cylinder head and satisfactorily retested the EDG. A shop test was Jerformed on the removed head to pinpoint the source of the oil leak, w1ich was determined to be a leaking exhaust valve seal. Visual inspection did not reveal any obvious deformation of the seal itself. The inspector questioned the o)erability of the EDG in this condition and the licensee indicated that t11s excess oil is only present when the Before and After (B&A) lube oil pum) is running. The B&A pump runs approximately 15 minutes out of eac1 hour when the EDG is in standby operation. Any excess fluid accumulated in the cylinder head would burn off during EDG
>
operation. During head removal from the engine, maintenance personnel also verified that no leakage was occurring from the piston, Conclusions
,
Corrective actions for the Unit 1A EDG 6L cylinder exhaust valve oil leak were prompt and effective. The root cause evaluation was thorough and it did not appear that a common mode failure existed. Station personnel were very knowledgeable of the EDG syste M3 Maintenance Procedures and Documentation M3.1 Maintenance - Work Control Process Measures a. Insoection Scooe (62707)
The inspectors reviewed the licensee's work process measures to evaluate licensee effectiveness in scheduling and completing maintenance activities for safety-related and important to safety equipment. The inspectors focused on the licensee's preventive maintenance activitie b. Observations and Findinas The inspectors reviewed Problem Investigation Process (PIP) Reports and work process measures, as well as interviewed maintenance and work control personnel, to evaluate preventive maintenance scheduling and '
completion. The ins)ectors noted that the licensee established an aggressive goal for 3reventive Maintenance (PM) and Periodic Testing (PT) activity completion. According to licensee documentation, the licensee had a year to date scheduled PM/PT completion rate of 89 percent. This value was slightly below the station goal of 90 percen The inspectors discussed the performance with the Work Control and Maintenance organizations and determined that although the performance in completion of PM/PT activities had significantly improved. some Enclosure a
-
- .
-
,.
l
process deficiencies existed. Specifically. the licensee's work execution policy does not prohibit completion of a work order task when the maintenance activity cannot be completed as scheduled. Guidance documents do not explicitly require that the tasks be rescheduled when
'the maintenance activity cannot be completed. In the event that the I
work-cannot be performed. Maintenance personnel are expected to make a specific notation stating that no work was performed and this information is to be reviewed by work control prior to entering the completed work order information into the automated Work Management Syste In the unlikely' event that the statement is not recognized during the review process, the work order will be entered into the system as complete and a new preventive maintenance schedule will be generated for the component. The current 3rocess does not require that a new work request / order be generated or tlat the original work order be voided. Voiding the work order results in an automatic rescheduling of the PM/PT. The inspectors emphasized that the ability to identify a preventive maintenance activity as complete when no maintenance has been performed was a work process deficiency. The inspectors referred this issue to licensee managemen . Conclusions The inspectors concluded that the licensee's )erformance in meeting established work management goals was goo Prioritization of work activities was evident. Although no instances of missed PM/ pts were identified. some process deficiencies were note III. Enaineerina E4 EngineeringStaffKnow;adge-andPerformance E4.1 Temocrary Modification for Instrument Air Use Durina S/G Maintenance Insoection Scoce (3755D Following the Unit 2 shutdown to repair primary to secondary leakag engineering personnel, conducting an instrument air system performanc assessment, recognized that the maintenance personnel had improperly connected air supply hoses from the instrument air system to the primary loop nozzle dam seals. The inspectors evaluated the licensee's response
.,
to this issue, Observations and Findinas
__The instrument air system was being used to supply air to maintain nozzle dam seals during steam generator maintenance activities. The engineer immediately realized that the use of instrument air as a supply for the nozzle dam seals required a temporary modification (TM). but none had been processed. The engineer immediately informed the maintenance crews that the air supply source for the seals should be the station air system. The engineer requested that the supply be realigned to station air until a temporary modification could be processed. The Enclosure
.
. .. .
~
. .
_ .. .
..
. _ . - _ _ _ _ _ _ _ _
. .
.
maintenance crews realigned the system and station engineering was instructed to provided a TM package, However, Operations managemen recognizing the potential safety consequences of the realignment, instructed the maintenance crews to continue using instrument air for reliability. Although station air is provided by the instrument air system, during certain events, station air may be isolated. The licensee had not formally evaluated the potential consequences of hose failures and the resulting affect on the instrument air syste The inspectors interviewed Engineering. Operations and Maintenance personnel, and were informed that the use of instrument air was the ,
preferred method for nozzle dam installation. The licensee recognized that the maintenance practice of connecting supply hoses to the instrument air system for nozzle dam installation had not been reviewed, The licensee immediately performed evaluations to justify the use of instrument air and completed the TM review to allow the maintenance crews to continue the re) air activities. Following completion of steam generator maintenance, tle TM was closed and actions were implemented to recognize instrument air as the preferred steam generator nozzle dam air supply. The initial failure to implement the TM process constitutes a violation of minor significance and is being treated as a Non-Cited Violation (NCV), consistent with Section IV of the NRC Enforcement Policy: NCV 50-369,370/97-10-02, Failure to Implement TM Process, Conclusions The licensee's decision to complete a TM and continue using the instrument air system was, in this case, acceptable. The responsible engineer's immediate and detailed investigation of system performance was indicative of a good uestioning attitude. A NCV was identified for the initial failure to im lement the TM proces E6 Engineering Organization and Administration E6.1 Ooeratina Experience Proaram Effectiveness a. Insoection Scoce (37551)
The inspectors reviewed the Duke Power Operating Experience Program (0EP) effectiveness in evaluating applicable information from within Duke Power Company and the i@stry on events and problems that may potentially impact nuclear safety and equipment reliability. The Operating Experience Assessment (0EA) Organization had the administrative lead for the implementation of the OEP responsible for receipt, evaluation, and resolution tracking of the issue b. Observations and Findinas The inspectors reviewed selected industry operating experience reports provided through the licensee's OEP, whicn documented events identified at Duke facilities and other power reactor facilitie The inspectors noted that the OEP had provided detailed information of events and findings at other facilities and had established a technical contact to Enclosure
_
m
.
.
.
I
ensure that site specific reviews were complete The inspectors noteJ that the OEA provided timely notification of NRC and industry issues identified in Information Notices. Bulletins, and vendor advisory letters. The inspectors reviewed the following OEP items to evaluate OEP effectiver.ess:
. Information Notice 91-50. Supplement: Water Hammer Events Since 1991
. Operating Experience Database No. 97-014266. Auxiliary Feedwater Pump Overspeed Following Restart The inspectors confirmed that this operating experience information was expeditiously distributed to the responsible station engineer and was adequately tracked through the licensee's Problem Investigation Proces c. Conclusions The inspectors concluded that the OEP has adequately assisted the McGuire Nuclear Station in timely evaluation and resolution of relevant industry issues. Site specific actions to resolve the issues have adequately sustained nuclear safety and equipment reliabilit E7 Quality Assurance and Engineering Activities E Radioloaical Consecuences of a Fuel Handlina Accident Involvina Hiah-3urnuo Fuel Insoection Scoce (37551)
During a review of the fuel handling activities in the Unit 1 spent fuei pool, the inspector reviewed UFSAR Section 15.7.4. Fuel Handling Accidents in the Containment and Spent Fuel Storage Facilities, and identified an issue with the UFSAR assumptions usei for the spent fuel handling accident. Station personnel were interviewed and licensee documents were examine b. Observations and Findinas lhe inspector identified an unresolved issue concerning the isotopic gap fractions assumed in the McGuire UFSAR Table 15-35. Maximum McGuire Spent Fuel Assembly Fission Product Inventories Assumed for Fuel Handling Accidents. Gap fraction is defined as the fraction of the total isotopic inventory residing in the gap between the fuel pellets
, and the rod cladding. As noted on the bottom of UFSAR Table 15-35. the gap fractions are from Regulatory Guide (RG) 1.25. Assum3tions Used for Evaluating the Potential Radiological Consequences of a uel Handling g Accident and Storage Facility for Boiling and Pressurized Water
-
Reactor These gap assumptions are: (1) 10 percent of the total noble gases other than Krypton-85; (2) 30 percent of the Krypton-85: and (3)
10 percent of the total radioactive iodine in the rods at the time of the postulated acciden Enclosure l
l J
. .
-~
.
The inspector reviewed RG 1.25 and identified as noted in regulatory-position C.1. that the assumptions related to the release of radioactive material from the fuel as a result of a fuel handling accident are valid only in cases where the average burnup for the peak. assembly does not exceed 25.000 MWD / ton. Regulatory position C,1 also notes that maximum-fuel rod pressure is 1200 psig. The McGuire spent fuel pools contain high burnup fuel (e.g., 40,000 MWD /mtu).
The inspector cuestioned the licensee if the assumptions were evaluated prior to exceecing the burnup limit specified in RG 1.25. The inspector was concerned that the assumptions used may not be adequate given the higher. burnuas and that the rate of fission gas release would tend to increase wit 1 increased burnu) and additional fragmenting of the pellets. This would affect tie assumed internal rod pressure (a '
function of all-fission gas) and the gap activity (a function of only dose contributing isotopes).
At McGuire, use of higher enriched fuel for storage in the spent fuel pool was approved in 1995. The inspector reviewed the license amendment .
request and subsequent NRC approval dated November 6, 1995. There was no specific evaluation of the release fraction assumptions, internal rod pressures, or reference to RG 1.2 In response to the inspector's concern, reactor engineering personnel reviewed data from the Oconee nuclear station for high burnup fuel performance and indicated that fission gas release rates were on the order of several aercent. The inspector noted that it ap) eared that this M ta was gatlered through B&W lead test assemblies (_TAs) and that LTAs are typically restricted-from being located in peak power locations in the core. Given this, fuel centerline temperatures would not have been as high as a peak assembly.- and consequently fission gas release rates would-have been low lince release rates are directly dependent on-fuel- temperature.-
-A second point raised by the licensee was that the new source term outlined in NUREG-1465. Acci' lent Source Terms for Light-Water Nuclear Power Plants, suggests a value of 5 percent for gap activity. The ins)ector reviewed this and noted that the new source term may not cover higi burnup fuel. Also, for reactor accident cialysis, use of a 5 percent value as a core-average gap fraction may be appropriate since typically one-third activity) and of the one third core of the haswill core low burnup have (virtuallyburnup a moderate no gap (a very small amount of gap activity). However, for the fuel handling accident, the bounding accident involves the highest burned assembly and use of a core average value for gap activity would not appear to be appropriat Conclusions The inspector concluded from the information reviewed, that the licensee may not have evaluated if the isotopic gap-fractions used in UFSAR Table 15-35 for the fuel handling accident analysis were valid for high burnup fuel prior to exceed +ng the burnup limit specified in Regulatory Guide 1.25 (basis for the table). Insufficient information existed to Enclosure
-- - - . -- - -- -- - -. -
a
_ _ _..__ _ _ -
. .
-
.
determine if the radiological consequences of an accident involving a highly burned fuel assembly.are acceptable. Pending additional inspector review, this issue is identified as Unresolved Item (URI) 50-369,370/97-10-01, Radiological Consequences of a Fuel Handling Accident Involving High Burnup Fue IV. Plant Suooor_t R1_ _ Radiological Protection and Chemistry Controls R1.1 Occuoational Radiation Exoosure Control Proaram Insoection Scooe (83750)
t The-inspectors observed and reviewed licensee activities to determine the adequacy of the licensee's radiological controls, as required by 10 Code of. Federal Regulations (CFR) Parts 20.1201, 20 1501, 20,1601.- '
20.1801. 20.1902 and 20.190 Observations and Findinas During the week of' July 7-11, 1997, the inspectors made frequent tours of Radiologically Controlled Areas (RCAs). Units 1 and.2 were operational at the time of the inspection. The inspectors toured Auxiliary Building facilities Units 1 and 2 Turbine Buildings, and selected radioactive waste processing and storage areas. During the tours, the' inspectors performed observations of radiological-protection activities, including pre-work briefings, personnel monitoring, radiological postings, and high radiation area controls. Radiologically ,
Controlled Areas observed were appropriately posted and radioactive materials observed were appropriately stored and labeled, The-inspectors' reviewed Operational and Administrative-controls for entering the RCA and performing work. These controls included the use of Radiation Work Permits (RWPs) to be reviewed and understood by workers prior to entering the RCA. The inspectors reviewed selected RWPs for adequacy of the radiation protection requirements based on work scope, location, and condition For the RWPs reviewed, the inspector noted that appropriate protective clothing and dosimetry were required, The
.
inspectors performed independent radiation and contamination-surveys of selected areas in the Auxiliary Building and outside storage areas. The inspectors surveys confirmed RWP requirements and licensee survey _
~informatio At the time of the insp'ection, radiological housekeeping was observed to be good. Contaminated square footage was less than 0.05 percent (300 square feet) of the total RCA of 114,765 square feet, Records revi sed determined the-licensee was= tracking and trending Personnel Contamination Events (PCEs). The licensee had tracked approximately 148 PCEs for 1997. The 148 PCEs recorded included 43 skin contaminations and 105 clothing contamination Enclosure s
. .
'
.
The inspectors reviewed and discussed with licensee representatives the 1997 Total Effective Dose Equivalent (TEDE) exposures for plant and contract personnel. Through reviews of selected cose records and discussions with licensee representatives. the inspector confirmed that all TEDE exposures assigned during the period were being maintained well below regulatory limits of 10 CFR Part 20 limits. At the time of the inspection, the licensee had not detected any internal exposures in 1997 at reportable limits. A discussion with licensee representatives and a review of pertinent records determined that the licensee had established an annual site exposure goal of approximately 288.3 person-rem as of July 1.1997. Site ex approximately 251.3 person-re Theposure actually exposure total radiation accrued in 1997 was accrued as of July 1,1997, was based on operational radiation exposure of 1 person-rem, a Unit 1 S/G replacement outage radiation exposure of 13 erson-rem a unit I refueling outage exposure of 98.8 person-rem. and a Jnit 2 forced outage radiation exposure of 5.2 person-rem to repair S/G tube leak The inspectors also observed ongoing work in the Retired Steam Generator Storage Facility to remove selected 31eces of tubes from a retired S/G.
<
This project was contracted through ) uke Engineering Services (DES) and Argonne National Laboratory in su) port of a contract between the Nuclear Regulatory Commission (NRC) and t1e Department of Energy (DOE) as previously discussed in NRC Inspection Report 50-369.3/0/97-09. Work observed during this project included: pre-work briefings, the performance of contamination and radiation surveys, radioactive material control and storage, postings, contamination controls, airborne controls and radiation exposure controls. The use of tent containments. High Efficiency Particulate Air (HEPA) filtered ventilation, wireless communications, teledosimetry, cameras, and other work practices were effective methods the licensee was using to maintain radiation exposures As low As Reasonably Achievable (ALARA). Specific work procedures and radiation work permits (RWPs) were reviewed and personnel were observed during the S/G tube pull project to be in compliance with the procedures and RWPs. The RWPs adequately addressed ALARA considerations, external and internal exposure controls, and contamination controls for the expected radiological hazards. Ap3roximately 14 person-rem had been accrued early in the project, whic1 was above the licensee's goal for that portion of the work scope by approximately 3 person-rem. The additional exposure was attributable to mechanical problems ~ during tube cutting and tube pullin Re-tooling of the tube cutting and pulling equipment enhanced performance and the licensee was able to reduce exposures below original goals after pulling 8 of 11 tubes to be aulle The licensee originally established a goal of 35 person-rem for t1e entire S/G tube and tube sheet removal project. Based on observations of work and discussions with licensee and contractor personnel, the inspectors determined licensee management oversight of the project was good and the licensee had continued efforts to maintain exposures ALAR Enclosure s . ..
._ . .
. _ . J
, .
4-17 Conclusions Radiological facility conditions and housekeeping in radioactive waste storage areas were good. Material was labeled appropriately, and areas were properly posted. All exposures were below regulatory limits and-the licensee was continuing to maintain exposures As low As Reasonably Achievabl R5 Staff Training and Qualification in Radiation' Protection and Control-R5.1 Trainina Activities for Radiation Protection Technicians
= Insoection Scooe (83750)
The inspectors observed licensee training to ensure personnel had been instructed in precautions and procedures to minimize exposure as required by 10 CFR Part 19.12 and applicable Technical Specification (TS) requirements, Observations and Findinas The inspectors reviewed-training requirements for radiation protection technicians The continuing training schedule for 1997 consisted of selected topics to enhance worker performance in the area _of radiological controls. -Industry events were being incorporated into the training. In addition to observing work performed by radiation protection technicians, the inspectors interviewed technicians to assess their level- of knowledge in the area of radiation protection. All persons observed performing work and interviewed by the inspectors appeared to be well trained, Conclusions Based on a review of training activities for radiation protection technicians the inspectors determined radiation protection technicians were receiving an appropriate level-of training to accomplish the work activities observe S8 Miscellaneous Security and Safeguards Issues (92904, 71750)
S (Closed) IFI 50-369.370/97-02-01: Protected Area Illumination The inspectors reviewed the licensee's actions to address concerns relating to protected area illumination requirements. The licensee has developed more comprehensive procedures outlining expectations for security personnel commensurate with the potential safety significanc Since no violation of NRC = requirements was identified and the licensee took prompt actions to resolve the concerns. this issue is close Enclosure
,
. . _ . ---
'
.
.
V. Manaaement Meetinas X1 Exit Heeting Summary The inspectors ) resented the inspection results to members of licensee management at t1e conclusion of the inspection on August 7.1997. The licensee acknowledged the findings presented. The inspectors asked the licensee whether any materials examined during the inspection should be considered proprietary. No proprietary information was identifie Enclosure a
. ,
-
.
PARTIAL LIST OF PERSONS CONTACTED Licensee Barron, B., Vice President, McGuire Nuclear Station Boyle, J., Civil / Electrical / Nuclear Systems Engineering Byrum W., Manager, Radiation Protection ,
Cash, M., Manager, Regulatory Compliance Cross, R., Regulatory Compliance Dolan, B., Manager, Safety Assurance Geddie, E., Manager, McGuire Nuclear Station Herran, P., Manager Engineering Michael, R., Chemistry Manager Robinson, M., Manager, S/G Replacement Project Sample, M., S/G Maintenance Thomas, K., Superintendent, Work Control Travis, B., Manager, Mechanical Systems Engineering Tuckman, M., Senior Vice President, Nuclear Duke Power Company
,
NRC
! M. Sykes Acting Senior Resident inspector, McGuire '
M. Franovich, Resident inspector, McGuire ,
N. Economos. Regional Inspector D. Forbes, Regional Inspector
.
+
l Enclosure l ;
. .
-
.
I-
INSPECTION PROCEDURES USED IP 71707: Conduct of Operations IP 62707: Maintenance Observations IP 61726: Surveillance Observations IP 40500: Effectiveness of Licensee Controls in Ident ',ying and Resolving Problems IP 92904: Followup - Plant Support IP 83750: Occupational Exposure IP 93702: Prompt Onsite Event Response IP 37551: Onsite Engineering IP 71750: Plant Support IP 50001: Steam Generator Replacement IP 92902: Followup - Maintenance IP 627^0: Maintenance Implementation ITEMS OPENED, CLOSED, AND DISCUSSED OPENED 50-369.370/97-10-01 URI Radiological Consequences of a Fuel Handling Accident Involving High-Burnup Fuel (Section E7.1)
, 50-369,370/97-10-02 NCV Failure to Implement TM Process
'
(Section E4.1)
'
CLOSED
- 50-369,370/97-02-01 URI Protected Area Illumination (Section
.
S8.1)
.
LIST OF ACRONYMS USED ALARA - As Low As Reasonably Achievable
ASME -
American Society of Mcchanical Engineers
'
CA -
Main Feedwater CFR -
Code of Federal Regulations DES -
Duke Engineering Services EDG - Emergency Diesel Generator ESF -
Engineered Safety Feature FME -
, FWST - Feedwater Storage Tank GL -
Generic Letter GPD -
Gallons per Day IFI -
Inspector Fellowup Item Enclosure
,
d
-
--. .
~ aL '4 :
28 _ _
_
IR- - -- InspectioriReport MOV -
Motor-Operated Valve-MSSV -
[.
'
NCV -
Non-Cited Violation NDE- -
Nondestructive Examination-NRC -
Nuclear. Regulatory Commission NRR -
NRC Office of-Nuclear Reactor Regulation *
OEA -
Operating Experience Assessment OEP -
Operating Experience Program PCE -
Personnel Contamination Event PDR -
Public Document Room PIP -
Problem Investigation Process-PM/PT - Preventive Maintenance / Periodic Testing RCA- -
Radiologically Controlled Area RWP- -
Radiation Work Permit-SFP -
Spent Fuel Pool-SG -
Steam Generato TEDE - Total Effective Dose Equivalent TM -
Tem)orary Modification TS- - -
Tec1nical: Specifications UFSAR - Updated Final Safety Analysis-
-URI -
Unresolved Item-US0 -
Unreviewed Safety Question VIO -
-Violation WO- -
Work Order i
_ _
Enclosure
- ... . .
. _ . .
.
.
.
.
j