IR 05000397/1993016
| ML17290A452 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 06/04/1993 |
| From: | Ang W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML17290A450 | List: |
| References | |
| 50-397-93-16, NUDOCS 9306220171 | |
| Download: ML17290A452 (19) | |
Text
U.S.
NUCLEAR REGULATORY COMMISSION REGION V
~Re ort No.:
Docket No.:
50-397/93-16 50-397 License No.:
NPF-21 Licensee:
Washington Public Power Supply System (WPPSS)
il ti d
A i
Pi t,
A it t Benton County, Washington Ins ection Conducted:
May 3-7, 1993
~lns ectors:
D. Acker, Reactor Inspector A~At:
Ins ection Summar
U P.rgw C
ng, C ie
,
ngineering Section Ins ection durin the eriod of Ma 3-7 1993 Re ort No. 50-397 93-16 During this routine announced inspection the inspector reviewed open items,and observed outage maintenance.
Inspection Procedures 62703,
"Maintenance Observation;"
92700,
"Followup of Written Reports;"
92701,
"Followup;" 92702,
"Followup of Enforcement Actions;" and Temporary Instruction 2515/111,
"Followup of Electrical System Functional Inspection Items," were used for this inspection.
Safet Issues Mana ement S stem SIMS Item:
None.
Results:
General Conclusions and S ecific Findin s:
Based on industry information and their own cleaning requirements, the licensee had previously established a worst cast heat exchanger cooling efficiency of 80%.
The licensee performed worst case equipment and room temperature rise calculations using this worst case efficiency of 80%.
Recent testing of heat exchanger cooling coil performance discovered efficiencies as low as 68%.
The licensee was reevaluating room and equipment temperature calculations and minimum heat exchanger efficiencies during this inspection.
930b220171 930b04 PDR ADOCK 05000397
The licensee's corrective actions for most followup items were well documented and acceptable.
Two problems were noted:
A licensee error in calculating the reflection of solar energy from the spray pond was noted.
Assurance that adequate implementation of corrective actions for Violation 50-397/92-01-13 (failure to update procedures for installed design changes)
was not included in the licensee's closure package.
Si nificant Safet Matters:
None.
Summar of Violation or Deviations:
None.
0 en Items Summar
Seven open items were close DETAILS Persons Contacted Washin ton Public Power Su
S stem z.
- J. Baker, Plant Manager
- C. Fies, Licensing Engineer
- L. Harrold, Manager, Maintenance T. Neade, Supervisor, Site Electrical Engineering
- T. Hessersmith, Manager, Maintenance Support
- L. Oxsen, Deputy Hanaging Director
- K. Pisarcik, Licensing
- J. Sampson, Manager, Maintenance Production
- S. Washington, Manager, Nuclear Safety Engineering U.S. Nuclear Re ulator Commission K. Johnston, Senior Resident 1nspector, Trojan
- Denotes those attending the exit meeting on Nay 6, 1993.
The inspector also held discussions with other licensee personnel during the course of the inspection.
Maintenance Observation 62703 After failure of emergency diesel generator (EDG) number one in 1990, due to loss of lubricating oil, the licensee had the generator rotor overhauled.
During the overhaul, the licensee discovered that the rotor contained shorted turns.
The licensee had the affected windings replaced.
The licensee then tested the EDG number two rotor and discovered a partially shorted winding.
The licensee evaluated the condition as acceptable, and committed to monitor the rotor for further degradation.
In order to evaluate the continued satisfactory operation of the EDG number two rotor, the inspector witnessed performance of Plant Procedure Manual (PPH) 10.25. 144, Revision 1,
"DG Rotor Pole AC Voltage Drop Test,"
and compared the test results to previous tests.
The voltage drop test was being performed to check the condition of the rotor windings.
The licensee had continued to test the rotor over the last three years.
Previous tests had indicated no further degradation.
The inspector determined that the test results were correctly measured and were consistent with previous results.
The inspector concluded that the data was acceptable to show that additional shorts had not occurred.
The inspector also reviewed removal, labeling, and temporary storage of emergency diesel generator mechanical parts, in preparation for routine diesel overhaul.
No problems were noted.
Ho violations or deviations were noted in the areas reviewe.
Followu of Previousl Identified 0 en Items and Electrical Distribution S stem Functional Ins ection 0 en Items 92701 and TI 2515 111 Closed Followu Item 50-397 92-11-INN:
Reliabilit of Antici ated Transient Without Scram ATWS Miti ation S stem Ori inal NRC 0 en Item This item was opened to review the licensee's evaluation of Information Notice (IN) 92-06, "Reliability of ATWS Mitigation System and Other NRC Information Required Equipment not Controlled by Plant Technical Specifications."
NRC IN 92-06 provided examples where non-safety related ATWS equipment was not being adequately maintained or tested.
Licensee's Actions in Res onse to IN 92-06 The licensee completed review of IN 92-06 on December 17, 1992.
The licensee documented the review in Operating Event Review (OER)
Number 22122R.
The licensee concluded that they were performing adequate maintenance and testing of non-safety related ATWS equipment.
Ins ectors'ctions Durin the Present Ins ection The inspector reviewed OER 22122R.
The inspector reviewed the maintenance and testing being performed on ATWS equipment.
The inspector reviewed test data for Procedure 8.3. 109, Revision 1,
"ATWS-ARI Logic Test."
The inspector reviewed maintenance records for selected non-safety related ATWS equipment.
Discussion and Conclusion b.
The inspector concluded that the licensee had a program for routine maintenance of non-safety related ATWS equipment and that this program maintenance was being performed.
The inspector also concluded that this equipment was being routinely tested.
Based on existing maintenance and testing of non-safety related ATWS equipment, the inspector concluded that the licensee review of IN 92-06 was adequate.
This item is closed.
Closed Followu Item 50-397 92-01-02:
Inade uate Ultimate Heat Sink Anal sis Ori inal NRC 0 en Item The Electrical Distribution System Functional Inspection (EDSFI)
team identified a number of problems with calculations and assumptions associated with the ultimate heat sink.
The problems included:
~
The calculations assumed more water in the spray ponds then the minimum allowed by Technical Specifications.
~
The calculations did not include known pond leakage.
~
The Updated Final Safety Analysis Report (UFSAR) indicated that numerous components were analyzed for operability using non-conservative service water temperatures.
~
Service water temperatures measured at components were higher than calculated.
Based on these problems the team concluded that the maximum service water system temperatures had not been determined.
Licensee's Actions in Res onse to the 0 en Item The licensee performed new ultimate heat sink and service water temperature calculations to account for conservative spray pond levels and leakage.
The licensee modified UFSAR Table 9.2-5 to clarify service water system temperature assumptions.
The licensee performed an analysis of service water system temperatures and concluded that the previously measured service water temperatures were not accurate.
Finally, the licensee concluded that the ultimate heat sink met the design bases requirements under worst case conditions.
Ins ectors'ctions Durin the Present Ins ection The inspector reviewed the revised licensee calculations including Calculation ME-02-92-41, Revision 1,
"Room Temperatures during Design Basis Accidents."
Part 5 of Calculation HE-02-92-41 included ultimate heat sink calculations.
The inspector reviewed UFSAR Table 9.2-5.
Discussion and Conclusion The inspector determined that Calculation HE-02-92-41 utilized conservative spray pond levels and included known leakage rates.
The inspector determined that UFSAR Table 9.2-5 had been clarified to indicate proper service water temperatures.
The inspector determined that the licensee's analysis of the difference between calculated system temperatures and measured temperatures was acceptable based on reasonable calculations for pump and flow temperature losses and additions.
The inspector determined that Calculation HR-02-92-41, Section 2,
Paragraph 6 contained a non-conservative error. for spray pond so1ar heat loading.
Since Paragraph 6 was only a discussion of the conservatism in the calculation, the error did not affect the actual calculation results.
The licensee acknowledged the error,
and stated that it would be corrected during the next routine revision of the calculation.
The inspector considered that the licensee action was adequate.
The NRC Service Mater Inspection team (IR 50-397/93-201)
reviewed Calculation NE-02-92-41 and concluded that this calculation demonstrated that the service water system was capable of accomplishing its safety function.
Based on the inspectors satisfactory review of the resolution of the specific problems noted by the EOSFI team and the conclusion of the NRC Service Water Inspection team that the service water system had adequate cooling capability, the inspector concluded that the problems noted by the EDSFI team were adequately resolved.
Since the original errors found by the EDSFI team were found to have little safety significance, the inspector also concluded that the errors did not constitute a violation of NRC requirements.
This followup item is closed.
0 en Followu Item 50-397 92-01-04:
Emer enc Diesel Generator Room and Diesel Generator Electrical E ui ment Room Tem eratures Ori inal NRC 0 en Item The EDSFI team determined that calculations for the emergency diesel generator (EOG)
room and diesel generator electrical equipment room maximum temperatures were non-conservative.
The team determined that the calculations did not use the heat input from a fully loaded EOG, did not consider the heat input from the EDG room into the diesel generator electrical equipment room, and did not consider the heat input from large dropping resistors located in the electrical equipment room.
The team noted associated errors in the UFSAR.
The team was unable to conclude that the licensee had determined the most limiting room temperatures.
Licensee's Actions in Res onse to the 0 en Item The licensee performed new EOG and diesel generator electrical equipment room maximum temperature calculations and updated the UFSAR.
Ins ectors'ctions Durin the Present Ins ection The inspector reviewed the licensee's new temperature calculations and the licensee's temperature qualification records for selected electrical equipment.
The inspector reviewed the UFSAR, Chapters 3 and 9.
Calculation NE-02-92-43, Revision I,
"Room Temperature Calculation for DG building, Reactor building, Radwaste building, and SW Pump-house Under Design Basis Accident Conditions,"
contained the licensee's room temperature calculation Discussion and Conclusion The inspector determined that the NRC Service Water Inspection team (IR 50-397/93-201)
had reviewed the licensee's room temperature calculations, including Calculation HE-02-92-43, and had concluded that the licensee had determined the most limiting room temperatures and that maximum safety equipment temperatures were within design requirements.
The inspector independently reviewed the licensee's temperature qualification records for selected electrical equipment and determined that the established temperature limits were technically adequate.
The inspector reviewed the UFSAR and determined that the errors noted by the EDSFI team had been adequately resolved.
However, the inspector noted that Calculation HE-02-92-43 assumed worst case heat exchanger cooling coil efficiency of 80%.
Recent testing, after completion of Calculation HE-02-92-43, had determined that actual heat exchange cooling coil efficiencies were as low as 68%.
The licensee again performed room temperature calculations using a heat exchanger cooling coil efficiency of 60%
and determined that calculated worst case room temperatures were above electrical equipment temperature ratings.
The licensee was reviewing the problem to determine what minimum level of heat, exchanger cooling coil efficiency they could maintain and the effects of this efficiency rating on existing room worst case temperature calculations.
This item will remain open for NRC review of the worst case heat exchanger cooling coil efficiency chosen by the licensee for room temperature calculations, the methods the licensee will use to maintain actual heat exchanger cooling coil efficiency above the calculated worst case efficiency, and the final room temperature calculations.
This review will include other vital equipment room temperatures.
Closed Followu Item 50-397 92-01-05:
Vital E ui ment Room Tem eratures Ori inal NRC 0 en Item The EDSFI team determined that UFSAR, page 9.2-21 stated that an evaluation of electrical equipment room temperatures had been made at maximum service water temperature and all room temperatures were found to be within design limits.
The team noted that calculations showed that vital equipment rooms, such as the battery charging room, had worst case temperatures above the Technical Specification (TS) limit of 104 degrees Fahrenheit (F).
Licensee's Actions in Res onse to the 0 en Item The licensee performed new room temperature calculations and made changes to the UFSAR, Chapters 3 and Ins ectors'ctions Durin the Present Ins ection The inspector reviewed the worst case room temperature shown in Calculation HE-02-92-43 and the changes to UFSAR, Sections 3 and 9.
Discussion and Conclusion The inspector determined that the UFSAR changes clarified that the TS limit of 104 degrees F was for an operating unit, and was not the equipment qualification limit.
The TS required the licensee to shutdown the unit when selected vital room temperatures exceed 104 degrees F.
As noted in Section 3.c above, the NRC Service Water Inspection team had reviewed the licensee's room temperature calculations and had concluded that the licensee had determined the most limiting room temperatures.
The team concluded that maximum safety equipment temperatures were within design requirements.
Based on a clarified UFSAR and updated room temperature calculations, the inspector concluded that this item was adequately resolved.
This item is closed.
As noted in Section 3.c, the effects of lower than calculated heat exchanger cooling'efficiency on room temperature calculations remained.an inspection followup item.
Closed Followu Item 50-397 92-01-06:
Static Exciter Volta e Re ulator Cabinet Tem eratures Ori inal NRC 0 en Item The EDSFI team determined that the licensee had insufficient test data or analysis to support adequate static exciter voltage regulator (SEVR) cabinet cooling.
Testing in 1990 indicated a 32 degree F internal SEVR cabinet temperature rise.
Based on room temperature calculations, and the 32 degree F internal heat rise, the EDSFI team concluded that the SEVR cabinet would approach its short term temperature limit of 158 degrees F,
and exceed its long term limit of 122 degrees F.
The team noted..that the =licensee had procedures in place to remove the SEVR cabinet door when room temperatures exceeded 90 degrees F, however, the procedure allowed 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> for this action.
Licensee's Actions in Res onse to the 0 en Item The licensee reviewed and updated the temperature qualification of equipment in the SEVR cabinet.
The licensee performed another internal cabinet heat rise test.
The licensee used thermography to locate hot spots and provide a second check for the temperatures being measured with thermocouples.
The licensee
concluded that the test indicated that the SEVR cabinet temperatures would not exceed its short and long term temperature limits.
Ins ectors'ctions Durin the Present Ins ection The inspector reviewed the licensee's updated temperature qualification information for the SEYR cabinet and the licensee's temperature test data from Hay 27, 1992; titled,
"DG-) Exciter Cabinet Temperature Test Report."
Discussion and Conclusion The inspector determined that the short term temperature limit of 158 degrees F was based on approximately eight hours of testing at this temperature, during initial acceptance testing of the SEVR cabinet.
The long term temperature limit of 122 degrees F was based on vendor information.
The licensee calculated the worst case room temperature to be approximately 130 degrees F.
The Hay 27, 1992, test indicated that maximum SERV internal temperature increases were below 32 degrees F, both with the cabinet door installed and removed.
The inspector concluded that the licensee had adequate information to support the short and long term temperature limits of 158 degrees F and 122 degrees F, respectively.
The inspector concluded that the Hay 27, 1992, test provided adequate data concerning internal SEVR cabinet heat rises.
Based on calculated design bases accident maximum room temperature profiles and the SEVR cabinet internal temperature heat rises measured during the Hay 27, 1992, test, the inspector concluded that the SEVR cabinet internal temperature would exceed 122 degrees F for less than eight hours, and would not exceed the 158 degree F short term limit.
This item is closed.
Closed Followu Item 50-397 92-01-08:
Switch ard Control and Haintenance Ori inal NRC 0 en Item The EDSFI team noted that the licensee had an agreement with the Bonneville Power Administration (BPA) for work by BPA in the licensee's switchyard.
The team determined that testing and maintenance of switchyard equipment was not being performed in accordance with the agreement.
The team also determined that the agreement did not cover the following areas:
~
Notification of BPA personnel of important new issues
concerning nuclear switchyards.
Use of licensee safety procedures.
Periodic review of BPA work by the licensee.
~
Hethod of determining maintenance.
Inspection Reports 50-397/92-33 and 50-397/92-08 followed up on this item and noted that the licensee had decided to initiate two separate agreements with BPA, one for operation and one for maintenance and testing.
Inspection Report 50-397/92-08 determined that the operational agreement had been signed.
Inspection Report 50-397/92-08 concluded that this agreement contained adequate operational controls, including work authorization processes, control room notifications, and communication requirements.
Licensee's Actions in Res onse to the 0 en Item The licensee and BPA prepared and approved an agreement for maintenance and testing of switchyard equipment.
Ins ectors'ctions Durin the Present Ins ection The inspector reviewed the maintenance agreement titled,
"Statement of WPPSS/BPA Maintenance Responsibilities for WNP2 and Integrating Facilities," dated Harch 25, 1993.
Discussion and Conclusion The inspector concluded that the March 25, 1993, agreement adequately resolved the original EDSFI team issues.
Specifically, the inspector concluded that the agreement contained adequate plant and personnel safety administrative controls.
This item is closed.
Closed Followu Item 50-397 92-01-20:
Busses SM-7 and SM-8 Overcurrent verses Undervolta e Coordination Ori inal NRC 0 en Item The EDSFI team determined that the overcurrent protection for vital busses SH-7 and SH-8 was not properly coordinated with associated undervoltage protection.
These busses were designed to be transferred to an alternate source upon loss of voltage.
During a bus fault, the transfer to an alternate source was designed to be prevented.
However, the lack of proper coordination noted by the team could have allowed a faulted bus to be transferred to a backup source and cause tripping of the backup sourc Licensee's Actions in Res onse to the 0 en Item The licensee reviewed their SM-7 and SM-8 coordination and agreed with the team.
The licensee changed the time delay setting for the SM-7 and SM-8 undervoltage relay and added a second undervoltage relay to the backup source.
The licensee stated that these modifications would provide proper circuit breaker coordination for SH-7 and SM-8.
The licensee performed Calculation E/I 02-92-017, Revision 0,
"Medium Voltage (4. 16 KV 8 6.9 KV) Electrical/ Distribution System (EDS)
Phase Overcurrent Relay Settings," to show the new coordination.
Ins ectors'ctions Durin the Present Ins ection The inspector reviewed the proposed design changes and Calculation E/I 02-92-017, Revision 0.
Discussion and Conclusion The inspector determined that Calculation E/I 02-92-017 confirmed that the proposed design change would provide adequate overcurrent and undervoltage coordination for busses SM-7 and SH-8.
The licensee stated that they planned to make the design change during the present outage.
This item is closed.
No violations or deviations were identified in the areas reviewed.
Followu on Corrective Actions for Violations and Deviations 92702 and Tem orar Instruction 2515 111 a ~
Closed Deviation 50-397 92-01-09:
Batter Testin and Maintenance Not in Accordance with U dated Final Safet Anal sis Re ort Commitments Ori inal NRC Enforcement Item The EDSFI team determined that maintenance and testing of the Class 1E batteries was not being accomplished in accordance with IEEE 450-1975.
Paragraph 8.3.2. 1.7. 1 of the UFSAR committed to follow the requirements and recommendations of IEEE 450-1975.
Licensee's Actions in Res onse to the Enforcement Item The licensee, in their written response to this deviation, dated June 4,
1992, acknowledged the deviation and determined that their UFSAR needed to be changed to reflect exceptions they had made to IEEE 450-1975.
The licensee issued Amendment 47 to UFSAR, Section 8.3, dated November 1992, to document their exceptions to IEEE 450-199 Ins ectors'ctions Durin the Present Ins ection The inspector reviewed the UFSAR change, the licensee's battery TS, IEEE 450-1975, vendor maintenance recommendations, and battery surveillance procedures.
Discussion and Conclusion The inspector concluded that the UFSAR change clearly documented exceptions the licensee had taken with regard to IEEE 450-1975.
The inspector determined that battery surveillance procedures adequately applied the sections of IEEE-450 still committed to in the UFSAR.
The inspector reviewed the licensee*s
CFR 50.59 evaluation of the UFSAR change and determined that it was adequate.
The inspector concluded that the provisions of IEEE-450 being followed by the licensee were adequate to comply with their TS requirements and vendor recommendations.
This item is closed.
0 en Violation 50-397 92-01-13:
Failure to U date Procedures for Installed Desi n Chan es Ori inal NRC Enforcement Item The EDSFI team determined that the licensee had accomplished design changes which changed thermal overload models, however, the associated surveillance procedures 'still contained testing acceptance criteria for the original thermal overload models.
The team determined that surveillances had been performed using the wrong acceptance criteria.
The licensee reviewed the surveillance procedure data and concluded that the recorded data was within the acceptance criteria for the new thermal overload models.
The team agreed.
Licensee's Actions in Res onse to the Enforcement Item The licensee, in their written response to this violation, dated July 10, 1992, committed to correct the associated procedures, train personnel on this issue and develop a word searchable computer program.
The licensee stated that the computer program would aid design personnel in determining all the procedures affected by a design change.
The licensee subsequently obtained a
word searchable
.computer program titled, "Plant Procedures System,"
and loaded their plant procedures into this program.
Ins ectors'ctions Durin the Present Ins ection The licensee reported to the inspector that this item was ready for closing.
The inspector reviewed the corrected procedures and the computer progra N t
Discussion and Conclusion The inspector concluded that the thermal overload surveillance procedures had been properly updated to match actual installed models.
The inspector performed sample word searches using the computer search program, including a search for "thermal overloads."
The program properly identified the thermal overload surveillance procedures, including the procedures noted in the original violation.
The inspector considered that this program would aid in identifying procedures effected by plant changes.
The inspector also determined that the licensee had adequate training material available for proper use of the program.
However, the inspector could find no evidence that design engineering personnel were required to use the program, or that they were even aware its existence.
The inspector provided this conclusion to the licensee.
This item will remain open pending evidence that the committed computer search program is effectively being used.
No violations or deviations were identified in the areas reviewed.
Other 0 en Items 92700 92701 and 92702 The inspector checked on completion of other. followup items.
The licensee stated that their action on the following items was incomplete.
Followup Item 50-397/92-01-11 Followup Item 50-397/92-01-03 Followup Item 50-397/92-25-04 Followup Item 50-397/92-25-07 Control of Maintenance Diesel Generator Cooling Evaluation of Electrical Assemblies RCIC Lube Oil Analysis The inspector reviewed LER 90-06-00 during this inspection but did not complete this item.
These items will be rescheduled for future inspections.
No violations or deviations were identified in the areas reviewed.
~Ei<<i The inspector conducted an exit meeting on Hay 6, 1993, with members of the licensee staff as indicated in Section 1.
During this meeting, the inspector summarized the scope of the inspection activities and reviewed the inspection findings as described in this report.
The licensee acknowledged the concerns identified in the report.