ML17297B700
| ML17297B700 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 09/30/1982 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| NUREG-0857, NUREG-0857-S03, NUREG-857, NUREG-857-S3, NUDOCS 8210060006 | |
| Download: ML17297B700 (46) | |
Text
NUREG-0857 Supplement No. 3 Safety Evaluation Report related to the operation of Palo Verde Nuclear Generating Station, Units 1, 2, and 3 Docket Nos. STN 50-528, STN 50-529, and STN 50-530 Arizona Public Service Company, et al ~
U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation September 1982
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TABLE OF CONTENTS 1
INTRODUCTION AND GENERAL DISCUSSION.
- 1. 1 Introducti on.
1.9 Summary of Outstanding Issues...............
1.10 Confirmatory Issues.....
2 SITE CHARACTERISTICS 2.1 Geography and Demography.
- 2. 1.2 Exclusion Area Control.
2.4 Hydrologic Engineering.
2.4.4 Ultimate Heat Sink 2.4.4.2 Maximum Mater Use.
2.5 Geology and Seismology.
- 2. 5. 1 Geol ogi c Informati on.
2.5.2 Seismology
- 2. 5. 2. 3 Maximum Ear thquake..........
3 DESIGN CRITERIA - STRUCTURE, COMPONENTS, E(UIPMENT AND SYSTEMS....
3.9 Mechanical Systems and Components........
3.9.6 Inservice Testing of Pumps and Valves......
5 REACTOR COOLANT SYSTEM AND CONNECTED SYSTEMS..
- 5. 2 Integri ty of Reactor Coolant Pressure Boundary......
5.2.4 Reactor Coolant Pressure Boundary Inservice Inspection and Testing.
5.2.4.1 Evaluation of Compliance for Palo Verde Unit 1 with 10 CFR 50.55a(g).
~Pa e
1-1l-l 1-2 2-1 2-1 2-1 2-1 2-1 2
2-3 2-3 2-3 2-3 3-1 3-1 3-1 5-1 5-1 5-1 Palo Verde SSER3
TABLE OF CONTENTS (Continued) 6 ENGINEERED SAFETY FEATURES 6.4 Control Room Habitability.
6.6 Inservice Inspection of Class 2 and 3 Components...........
6.6. 1 Evaluation of Compliance for Palo Verde Unit 1 with 10 CFR 50. 55a(g) 8 ELECTRIC POWER SYSTEMS 8.2 Offsite Power Systems 8.2.2 Testabi lity.
9 AUXILIARYSYSTEMS.
9.2 Water Systems.
9.2.5 Ultimate Heat Sink.
9.4 Heating, Ventilation, and Air Conditioning (HVAC) Systems....
9.4.1 Control Room Area Ventilation System (Control Building HVAC Systems) 9.5 Other Auxiliary Systems.
- 9. 5. 4 Emergency Diesel Engine Fuel Oil Storage and Transfer System.
9.5.4.2 Emergency Diesel Engine Fuel Oil Storage and Transfer System.
17 PUALITY ASSURANCE 17.2 Organization.
17.3 equality Assurance Program.
17.5 Open quality Assurance Item.
~Pa e
6-1 6-1 6-1 6-1 8-1 8-1 8-1 9-1 9-1 9-1 9-1 9-1 9-1 9-1 9-1 17-1 17-1 17-3 17-4 Palo Verde SSER3
APPENDIX A APPENDIX 8 APPENDIX C
FIGURE 17.1 TABLE OF CONTENTS (Continued)
APPENDICES Continuation of Chronology of Radiological Review.......
Palo Verde Unit 1 Evaluation (Preservice Inspection)....
Principal Contributors LIST OF FIGURES Arizona Public Service Company Organization for PVNGS Operation.
~Pa es A-1 B-1 C-1 17-2 Palo Verde SSER3
1 INTRODUCTION AND GENERAL DISCUSSION
- l. 1 Introduction On November 13, 1981, the Nuclear Regulatory Commission (NRC) staff issued its Safety Evaluation Report (SER) relating to the application for licenses to operate the Palo Verde Nuclear Generating Station, Unit Nos.
1, 2 and 3
(PVNGS 1-3); Supplement Nos.
1 and 2 to the SER were issued on February 4, 1982 and May 17, 1982, respectively.
The application was submitted by the Arizona Public Service Company (APS or the applicant) on behalf of itself, the Salt River Project Agricultural Improvement and Power District, Southern California Edison
- Company, El Paso Electric Company, Public Service Company of New Mexico, Los Angeles'Department of Water and Power, Southern California Public Power Authority, and M-S-R Public Power Agency.
In the SER and its supplements, the staff identified certain issues where either further information was required of the applicant or additional staff effort was. necessary to complete the review of the application.
The purpose of this supplement is to update the SER by providing the evaluation of (1) additional information submitted by the applicant since Supplement No.
2 to the SER was issued, and (2) the matters that the staff had under 'review when Supplement No.
2 was issued.
Each of the following sections of this supplement is numbered the same as the section of the SER and its supplements that is being updated
- and, unless otherwise
- noted, the discussions are supplementary to and not in lieu of the previous discussions.
Appendix A to this supplement is a continuation of the chronology.
Appendix B is a staff evaluation of the preservice inspection results for Palo Verde Unit 1.
Appendix C is the list of principal contributors to the staff review.
1.9 Summar of Outstandin Issues Section 1.9 of Supplement No.
2 contained a list of outstanding issues.
Several of those issues were resolved after the issuance of Supplement No.
2.
These are listed below, along with the section of this supplement wherein their resolution ss discussed.
(1) Ultimate heat sink (2.4.4.2, 9.2.5)
(2) PSI/ISI program (3.9.6, 5.2.4, 6.6)
(3) Diesel generator tank corrosion (9. 5.4. 2)
(4) Impurity levels (17.5)
At this time, a number of outstanding issues remain to be resolved.
These are listed below along with the section of the SER and/or its supplements wherein each issue is discussed.
The resolution of these remaining issues will be addressed in a subsequent supplement to the SER.
(1) Emergency preparedness (2.3.3, 13.3)
(2) Ultimate heat sink (9.2.5)
Palo Verde SSER3
(3) Cable tray design (3. 7. 1)
(4) Seismic and LOCA loads (4.2. 1)
(5) PSI/ISI program (3.9.7, 5.2.4, 6.3.3.,
6.6)
(6) Equipment qualification (3. 10,
- 3. 11),
(7) Hydrogen in RDT room (6.2.5)
(8)
LOCA doses (6.4, 6.5.2, 15.4.8, III.D.3.4)
(9) Control system fai lures (7. 7. 2)
(10) Alternate shutdown (7. 4. 2, 9. 5. 1. 6)
(11) Undervoltage protection (8.4.7)
(12) Calibration standards (17.-5)
(13)
ACRS comment (18)
- 1. 10 Confirmator Issues Section
- 1. 10 of Supplement.
No.
2 contained a list of issues that had been essentially resolved to the staff's satisfaction, but for which certain confirmatory information was to be provided by the applicant.
Subsequent to the issuance of Supplement No. 2, the applicant provided the required confirmatory information for three of those issues.
These are listed below, along with the section of this supplement wherein the issue is resolved.
(1) Exclusion area control (2. 1.2)
(2) Maximum earthquake (2.5.2.3)
(3) Modifications to test programs (8.2.2)
At this time, information on the remaining confirmatory issues is still pending or under, staff review.
These are listed below along with the section of the SER and/or its supplements wherein each issue is discussed.
The resolution of these remaining issues will be addressed in a subsequent supplement,to the SER.
(1) Road modification on East Wash (2.4.2. 1)
(2)
Pump and valve operability (3. 9. 3. 2, II. E. 4. 2)
(3)
RCS monitoring (4. 4. 1)
(4) Pressure-temperature curves (5.3.2)
(5) Pressurized thermal shock, Units 2 and 3 (5. 3. 3)
(6) Valve, modifications (5.4.3, 6.2.4)
(7) Modifications to test programs (5.4.3, 6.2.6, 6.3. 1)
(8).Override, interlocks, and alarms (5.4.3,. 7.6.2,, 8.3.2. 1)
(9) TMI instrumentation (6.2. 1. 1)
(10) Setpoint values (6.2.4, 7.2.4)
(ll) CPC software (7.2.4)
(12) Confirmatory site visits (7.1.3.5, 8.1;- 9.5.,1)
(13) Containment electrical penetrations (8.4.3)
(14)
Load sequencer (8. 4. 6)
(15) Procedures (I. C. 1, II.B. 1, II.F. 2)
(16) Control room design review (I.D.1)
(17) Relief and safety valve tests. (II.D.1)
Palo Verde SSER3 1-2
2 SITE CHARACTERISTICS
- 2. 1 Geo ra h
and Demo ra h
- 2. 1.2 Exclusion Area Control In Sections
- 2. 1. 2 and 2. 1. 4 of the SER, the staff stated that it was unable to conclude that the applicant had the authority to determine all activities within the exlusion area because the staff was still reviewing the. rights to minerals in certain parcels within the exclusion area (Parcels B and C as shown on Figure 2.2 of the SER).
Subsequently, by letter dated April 1, 1982, the applicant provided additional information clarifying its authority to control all activity, lacking complete ownership of all mineral rights, with respect to land Parcels B,and C.
The applicant stated that it acquired Parcel B with the reservation that the Seller would retain a 50K interest in the mineral rights.
However, the language of the reservation specifically prohibits the Seller any ingress or egress to or from Parcel B for the purpose of recovering or developing oil, gas or other mineral deposits or geothermal resources, as well as the installation of any facilities for mineral recovery.
With respect to Parcel C, the applicant states that one-sixteenth of all gas, oil, metal and mineral rights in this parcel have been reserved to the State of Arizona.
However, the reservation for Parcel C provides that the State owns the royalty interest, rather than the mineral interest, and will only be able to colle'ct royalties and not have the right to explore and develop Parcel C.
The applicant states that the State has never issued any oil, gas or mineral leases for lands with a one-sixteenth interest during the 28 years of this statute's existence.
The staff has reviewed the information supplied by the applicant and, based on the fact that the owners of mineral rights within Parcels B and C cannot enter upon these parcels or explore for minerals, but retain only a royalty interest, the staff has concluded that the applicant has the requisite authority to determine all activities within the exclusion area, as required by 10 CFR Part 100.
Therefore, this matter has been resolved.
2'.4 H drolo ic En ineerin 2.4.4 Ultimate Heat Sink 2.4. 4.2 Maximum Water Use In Section 2.4.4.2 of the SER, the staff concluded that the spray ponds, which supply emergency cooling water, did not contain a 30-day water supply for the design basis meteorological conditions suggested in R.G. 1.27, "Ultimate Heat Sink for Nuclear Power Plants."
Subsequently, the applicant revised its analysis and agreed that the spray ponds contained only a 27-day supply of cooling water.
The staff's independent evaluation had shown a 28-day supply.
Palo Verde SSER3 2-1
R.G.
1.27 states that a cooling capacity of less than 30 days may be acceptable if it can be demonstrated that replenishment can be effected to ensure the continuous capability of the sink to perform its safety function, taking into account the availability of replenishment equipment and limitations that may be imposed on "freedom of movement" following an accident.
In a letter dated June 17, 1982, the applicant discussed its proposal for ensuring that there is a reliable source of water available which could be used to supply make-up water to the spray ponds when the 27-28 day supply is depleted.
The regional aquifer has been identified as the source of make-up water.
This aquifer has an area over 400 square miles and yields up to 2800'allons per minute (gpm).
During station operation, this aquifer wi 11 be used for domestic water supply.
There are currently three wells on site tapping the regional aquifer.
In its evaluation af make-up water to the spray ponds, the applicant postulated that a safe shutdown earthquake would occur and would render all three existing on-site wells inoperable.
It then discussed the actions that would be followed to assure that water from the regional aquifer could be supplied to the essential spray ponds within a 27-28 day period.
The initial action would be to determine the damage done to the existing wells and associated equipment and the time to place at least one well back in operation.
Should the damage occur to the well pumps, the applicant will have a spare pump and motor onsite.
The well p'umps are typical irrigation pumps and spare parts are available in the Phoenix area.
Only one well would be required because after 27 days of spray pond operation, the make-up water.
requirement would be less than 225 gpm per unit.
Each existing well has the capability to pump up to 1400 gpm.
If none of the three wells could be. restored to service within a predetermined time, action would be initiated to mobilize equipment to construct a new well.
The applicant estimates that a
new well or wells capable of delivering 1200 gpm to the spray ponds could be operational within 15 days.
Drilling could be expedited by on-site storage of materials.
There are several alternatives to conveying water from the wells to the spray ponds.
The applicant states that one alternative would be aluminum irrigation pipe that is readily available in Phoenix.
This pipe is delivered on a 3-4 day notice in 4000 foot loads.
The staff has reviewed the applicant's proposal and concludes that the regional aquifer is a highly reliable source of water because, (1) it encom-passes such a large area, and (2) the pumping rates at existing wells show that the yield of the aquifer is more than adequate to maintain the pumping rate which would be required to provide make-up water to the spray ponds.
The staff also concludes that it would be extremely unlikely that any natural phenomenon could render all three on-site wells inoperable such that at least one could not be placed back in operation.
However, if this could not be accomplished, the staff concludes that the applicant has demonstrated that a
new well could be drilled and put in operation to ensure the continuous operation of the spray ponds.
The applicant has committed to make the procedures to be followed to ensure this continued capability available for Palo Verde SSER3 2-2
staff review at least 60 days prior to fuel load.
The staff finds this commit-ment to be acceptable.
The staff, therefore, concludes that the PVNGS 1-3 meets the guidelines of R. G. l. 27 and the requirements of GDC 44.
This matter is now resolved.
- 2. 5 Geolo and Seismolo 2.5.1 Geologic Information In Section 2.5. 1 of the SER, the staff stated that no new information had been developed which indicated that the staff conclusions presented in the CP-SER for PVNGS 1-3, regarding the geologic suitability of the PVNGS site, should now be modified.
Subsequently, on May 26, 1982, Mr. Christopher M. Menges, Research Geologist of the State of Arizona, Bureau of Geology and Mineral Technology, notified the staff of anomalous geomorphic features (scarps),
possibly of tectonic (fault) origin, located 15 km (9.3 mi) northeast of the PVNGS site.
These features were identified by Mr. Menges as a result of a state wide study, funded by the U.S. Geological
- Survey, whose purpose was to identify quaternary faulting in the State of Arizona.
Dr. Larry D. Fellows, Arizona State Geologist, notified the applicant of these features on May 27, 1982.
As a result, the applicant conducted field investigations (trenching and detailed geologic mapping) on June 12 and 13, 1982 across the trend of the most prominent scarps.
The trenches were observed by both Mr. Menges (on June 12 and 13) and the NRC staff geologist (on June 17).
By letter, dated June 18, 1982, to the NRC, Mr. Menges concluded that the exploratory trenches indicate that the scarps are nontectonic in origin.
By letter, dated July 29,
- 1982, the applicant submitted the results of its field investigations and concluded that the scarps are due to normal processes of basin deposition and erosion.
The staff has reviewed these submittals and concurs with these assessments.
In conclusion, the trench excavations, coupled with other available surface and subsurface
- data, have demonstrated conclusively to Mr. Menges, the applicant, and the NRC staff geologist that the anomalous features are the result of non-tectonic erosional processes, not faulting.
Consequently, the features are not potentially hazardous and can have no effect upon the seismic design bases of PVNGS 1-3.
Therefore, the staff reaffirms its conclusion that no new informa-tion has been developed to alter the staff conclusions, presented in the CP-SER for PVNGS 1-3, regarding the geologic suitability of the PVNGS site.
- 2. 5. 2 Seismology 2.5.2.3 Maximum Earth uake In Section 2.5.2.3 of the SER, the staff stated that a study of historical seismicity in Arizona was being conducted by the Arizona Bureau of Geology and Mineral Technology, in cooperation with the Department of Geosciences at the University of Arizona.
This study was partly funded by the NRC and was recently published as NUREG/CR-2577, entitled "Historical Seismicity in Arizona", by S. M.'uBois, M.
L. Sbar and T.
A.
Nowak.
The study compiled and analyzed Palo Verde SSER3 2-3
felt reports and instrumental records for Arizona earthquakes and felt reports from the 1887 Sonora Mexico earthquake.
By letter, dated May 21, 1982, the applicant provided an evaluation of the above report and concluded that this recent assessment of historical seismicity in Arizona strongly suggests that the approach used to define the regional seismicity and to develop the seismic design criteria for PVNGS 1-3 was, in fact, conservative.
The staff finds that no new information has been developed during this study indicating that the earlier conclusions reached by the staff regarding the suitability of the PVNGS site should now be modified.
The NRC staff consultant for the PVNGS site, Los Alamos National Laboratory, has also reviewed the report and finds no impact on the seismic design.
Therefore, this matter is now closed.
Palo Verde SSER3 2-4
3 DESIGN CRITERIA " STRUCTURE, COMPONENTS, EQUIPMENT AND SYSTEMS 3.9 Mechanical S stems and Com onents 3.9.6 Inservice Testing of Pumps and Valves Section 3.9.6 of the SER stated that the staff's review of the preservice and inservice testing program for pumps and valves would be discussed after the program is submitted by the applicant.
Subsequently, the applicant submitted a description of its proposed testing program for pumps and valves in a letter from E.
E.
Van Brunt, Jr. to R.
L. Tedesco dated April 12, 1982.
The program includes both baseline preservice testing and periodic inservice testing.
It provides both for functional testing of components in the operating state and for visual inspection for leaks and other signs of degradation.
Specific written relief from certain ASME Code requirements was requested by the applicant.
The staff has not completed a detailed review of the applicant's submittal.
- However, based on a preliminary review, the staff finds that it is impractical within the limitations of design,
- geometry, and accessibility for the applicant to meet certain of the ASME Code requirements.
Imposition of those require-ments would, in the staff's view, result in hardships or unusual difficulties without a compensating increase in the level of quality and safety.
The relief requested will not endanger life or property and is in the public interest.
Therefore, pursuant to 10 CFR Part 50. 55a, the relief that the applicant has requested from the pump and valve testing requirements of 10 CFR Part 50.55a, Sections (g)(3) and (g)(4)(i), is granted for that portion of the initial 120-month period during which the staff completes its review.
Palo Verde SSER3
5 REACTOR COOLANT SYSTEM AND CONNECTED SYSTEMS 5.2 Inte rit of Reactor Coolant Pressure Boundar 5.2.4 Reactor Coolant Pressure Boundary Inservice Inspection and Testing 5.2.4. 1 Evaluation of Com liance for Palo Verde Unit 1 with 10 CFR 50.55a A Preservice Inspection (PSI)
Program for Palo Verde Unit 1 was submitted by the applicant in a letter dated November 13, 1981.
The PSI Program is based on the 1974 Edition of Section XI of the ASME Code including Addenda through Summer 1975.
Specific written relief from certain Code requirements was requested and supported by information in a letter dated April 6, 1982.
The staff has determined that certain ASME Code Section XI examination require-ments defined in 10 CFR Part 50, Section 50.55a(g)(3) are impractical.
The staff has evaluated the ASME Code required examinations that have, been determined to be impractical
- and, pursuant to 10 CFR Part 50, Section 50.55a(a)(2),
has allowed relief from the requirements that, if implemented, would result in hardships or unusual difficulties without a compensating increase in the level of quality and safety.
Based on the granting of relief from these preservice examination require-
- ments, we conclude that the preser vice inspection program for Unit 1 is in compliance with 10 CFR Part 50, Section 50.55a(g)(3).
The detailed evaluation supporting this conclusion is provided in Appendix B to this supplement.
Palo Verde SSER3 5-1
~
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6 ENGINEERED SAFETY. FEATURES 6.4 Control Room Habitabilit After the issuance of the SER, the applicant, in Amendment No.
8 to the
- FSAR, deleted the redundant chlorine gas detectors for the control building essential HVAC system outside air intakes.
Since no chlorine is stored at the site, this change is acceptable to the staff.
Section 9.4. 1 of this supplement also addresses this change.
To reflect this change, the following discussion replaces the second paragraph of Section 6.4 of the SER in its enti rety.
The control room ventilation system is automatically transferr ed to the emergency mode of operation upon receipt of a high radiation signal from the outside air intake duct detectors, a safety injection signal, a loss of power signal, or a fuel building high radiation signal.
The emergency ventilation system is provided with two identical, physically separated, high efficiency filtration trains with charcoal absorbers to process pressurization and recirculation air flows in the control room.
The transfer to the emergency mode of operation may also be manually initiated from the control room.
In the evaluation of the potential toxic gas hazard to control room personnel, the staff determined that toxic gases are not proposed to be stored,
- used, or transported on-or off-site in quantities sufficient to necessitate the control room protection measures described in SRP Section 6.4, RG 1.78 and RG 1.95.
6.6 Inservice Ins ection of Class 2 and 3
Com onents 6.6. 1 Evaluation of Compliance for Palo Verde Unit 1 with 10 CFR 50.55a(g)
A Preservice Inspection (PSI)
Program for Palo Verde Unit 1 was submitted by the applicant in a letter dated November 13, 1981.
The PSI Program is based on the 1974 Edition of Section XI of the ASME Code including Addenda through Summer 1975.
Specific written relief from certain Code requirements was requested and supported by information in a letter dated April 6, 1982.
The staff has determined that certain ASME Code Section XI examination require-ments defined in 10 CFR 50.55a(g)(3) are impractical.
The staff has evaluated the ASME Code required examinations that have been determined to be impractical and, pursuant to 10 CFR Part 50.55a(a)(2),
has allowed relief from the requi re-ments that, if implemented, would result in hardships or unusual difficulties without a compensating increase in the level of quality and safety.
Based on the granting of relief from these preservice examination requirements, the staff concludes that the preservice inspection program for Unit 1 is in com-pliance with 10 CFR 50. 55a(g)(3).
The detailed evaluation supporting this conclusion is provided in Appendix B to this supplement.
Palo Verde SSER3
8 ELECTRIC POWER SYSTEMS 8.2 Offsite Power S stems
- 8. 2. 2 Testabi 1 ity Section 8.2.2 of the SER states that the applicant provided a commitment to test switchyard components and perform periodic inspection and maintenance of all the switchyard and onsite power components.
Subsequently, in Amendment No.
6 to the FSAR, the applicant described in Section 8A the periodic inspection and maintenance program for the above components, except for the breakers associated with the 525 kilovolt switchyard.
By letter dated May 6, 1982, the applicant described the testing and maintenance program for the breakers associated with the 525 kilovolt switchyard.
The staff has reviewed the information relating to these programs and finds the programs to be in confor-mance with the requirements of GDC 18 and,
- hence, to be acceptable.
Therefore, this matter is now closed.
Palo Verde SSER3
I
9 AUXILIARYSYSTEMS 9.2.5 Ultimate Heat Sink Section 9.2.5 of the SER stated that independent staff review of the ultimate heat sink water capacity had indicated that sufficient water capacity may not be available in the essential spray ponds for a 30-day period without additional makeup as indicated in the guidelines of Regulatory Guide 1.27.
Subsequent analyses provided by the applicant in Amendment No.
8 to the FSAR have verified that a capacity of 27 days of water supply is available in the spray ponds for design basis accident (LOCA) heat loads assuming the worst historical site meteorolo'gy.
This is acceptable as discussed in Section 2.4.4.2 of this supplement.
Thus, the CESSAR interface requirements for ultimate heat sink capability, as discussed in CESSAR Section
- 9. 2. 2 and 9.2.5, are satisfied.
Therefore, this matter has been resolved.
9.4 Heatin Ventilation and Air Conditionin HVAC) S stems 9.4. 1 Control Room Area Ventilation System (Control Building HVAC Systems)
In Amendment 8 to the FSAR, the applicant deleted the redundant chlorine gas detectors for the control building essential HVAC system outside air intakes previously described in the SER.
This change is acceptable as no chlorine is stored at the site.
Therefore, the requirements of GDC 19, "Control Room,"
are met and the guidelines of RG 1.95, "Protection of Nuclear Power Plant Control Room Operators Against an Accidental Chlorine Release,"
are not applica-ble.
Refer to Section 6.4 of this SER supplement for further discussion on this change.
9.5 Other Auxiliar S stems 9.5.4 Emergency Diesel Engine Fuel Oil Storage and Transfer System 9.5.4.2 Emer enc Diesel En ine Fuel Oil Stora e and Transfer S stem As stated in Section 9.5.4.2 of the SER, internal corrosion protection for the diesel engine fuel oil storage
- tanks, as required by Section 7.5 of ANSI-N195 and Regulatory Guide
- 1. 137, was not being provided.
The applicant has designed the storage tanks with a 1/8" corrosion allowance.
External corrosion protection as well as cathodic protection has been provided for the tanks to minimize external corrosion.
The staff required that the applicant provide an internal protective coating on the tanks to prevent internal corrosion.
Subsequently, in a letter dated July 15, 1982, the applicant provided justifi-cation for not requiring internal protection for the diesel engine fuel oil storage tanks.
The applicant interprets a corrosion allowance as meeting the corrosion protection requirements of Section 7.5 of the ANSI standard.
The Palo Verde SSER3 9-1
l staff disagrees with this interpretation.
A corrosion allowance is an added safety factor in the system design which takes into account the expected corrosion over the life span of the system.
It does not provide corrosion protection or means to minimize corrosion as required by Regulatory Guide 1. 137.
In the July 15 letter, the applicant also provided the results of an analysis which showed that, due to meteorological conditions of the area (low humidity, desert region),
under worst case conditions very little moisture would accumulate in the fuel oil storage tank by tank breathing and ambient moisture condensation over a 3-month period.
In addition the periodic (quarterly) drainage of water accumulation, the use of high quality fuel (water and sediment content less than 0.05K volume),
and keeping the fuel oil tanks nearly full, assures the staff that internal corrosion wi 11 be negligible over the lifetime of the plant.
On the basis of the above, the staff concurs with the applicant that internal coating of the diesel engine fuel oil storage tanks is not required.
Therefore, the staff finds the design acceptable.
Based on its review, the staff concludes that the emergency diesel engine fuel oil storage and transfer system meets the requirements of General Design Criteria 2, 4, 5, and 17, meets the guidance of the cited Regulatory Guide and Standard Review Plan 9.5.4, can perform its design safety function and meets the recommendations of.NUREG/CR-0660 and industry codes and standards, and is, therefore, acceptable.
Therefore, this matter is resolved.
Palo Verde SSER3 9-2
17 QUALITY ASSURANCE In Section
- 17. 2 of the SER, the staff had completed its evaluation of the organizational structure of the operations phase quality assurance program for PVNGS 1-3.
Subsequently, in Amendment No.
9 to the FSAR, the applicant provided a realignment of the organizational structure.
The Corporate Quality Assurance
- Manager, who was previously under the direction of the Vice President, Nuclear Projects Management, now reports directly to the Operations Executive Vice President and Chief Operating Officer.
The PVNGS Operations QA/QC Manager, who was previously under the direction of the Manager of Nuclear Operations, now reports directly to the Corporate Quality Assurance Manager.
This organiza-tional realignment provides additional independence of the quality assurance
. function as compared to the previous organizational structure and, therefore, is also acceptable.
To reflect the above
- change, the following discussion replaces Section 17.2 of the SER in its entirety.
The structure of the organization responsible for the operation of PVNGS 1-3 and the establishment and execution of the operations phase quality assurance program is shown in Figure 17. 1.
The Operations Executive Vice President and Chief Operating Officer of the Arizona Public Service Company is responsible for promulgating the quality assurance program requirements.
He has ultimate responsibility for quality assurance of PVNGS 1-3.
The Nuclear Projects Management Vice President, the Electric Operations Vice President, and the Corporate Quality Assurance Manager each report to the Executive Vice President and Chief Operating Officer.
The Nuclear Projects Management Vice President is responsible for engineering and design support, construction of major modifications, and records manage-ment.
Verification that such activities comply with requirements of the Opera-tions Quality Assurance Program is the responsibility of the Corporate Quality Assurance Manager.
The Electric Operations Vice President is responsible for operation of PVNGS 1-3.
He has the responsibility for establishing controls necessary to ensure that station activities are performed in accordance with the Operations Quality Assur-ance Program.
The Electric.Operations Vice President's day-to-day responsibil-ities for the operation of PVNGS 1-3 have been delegated to the PVNGS Manager of Nuclear Operations.
The PVNGS Manager of Nuclear Operations reports directly to the Electric Operations Vice President and has the responsibility for di recting station operation and maintenance activities during the operations phase.
The Corporate Quality Assurance Manager is responsible for development of the Operations Quality Assurance Program and for verifying effective implementation of the Operations Quality Assurance Program.
He reports directly to the Operations Executive Vice President and Chief Operating Officer.
The Corporate Quality Palo Verde SSER3 17-1
EXECUTIVE VICE PRESIDENT AND CHIEF OPERATING OFFICER ELECTRIC OPERATIONS VICE PRESIDENT ENGINEERING AND CONSTRUCTION VICE PRESIDENT GAS OPERATIONS VICE PRESIDENT NUCLEAR PROJECTS MANAGEMENT VICE PRESIDENT RESEARCH AND DEVELOPMENT VICE PRESIDENT MANAGER OF NUCLEAR OPERATIONS ADMINISTRATIVE SUPPORT OPERATIONS AND MAINTENANCE ADMINISTRATIVE SERVICES MANAGER PROCUREMENT AND CONTROL MANAGER QUALITY SYSTEMS AND PROGRAMS PVNGS CONSTRUCTION QA/QC PVNGS OPERATIONS QA/QC PV/lGS START-UP QA/QC CORPORATE QUALITY ASSURANCE MANAGER TECHNICAL SUPPORT STARTUP FIGURE 17.1 ARIZONA PUBLIC SERVICE COMPANY ORGANIZATION FOR PVNGS OPERATION
Assurance Manager directs the activities of the Corporate Quality Assurance Department and provides functional direction and technical guidance to the Quality Assurance Managers.
The Corporate Quality Assurance Manager has overall responsibility for the quality assurance program including audits and quality verification.
He and his.staff, (1) develop the operations quality assurance criteria, (2) prepare and control the Operations Quality Assurance Criteria Manual which is concurred with by the Nuclear Projects Management Vice President and the Electric Operations Vice President and approved by the Operations Executive Vice President and Chief Operating Officer, (3) verify the implementation of the quality assurance program; (4) verify the adequacy of quality training programs, (5) review procurement documents, procedures, and instructions to assure inclusion of appropriate quality assurance require-
- ments, and (6) conduct internal audits of the Operations Quality Assurance Department-and external audits of suppliers.
The PVNGS Operations QA/QC Manager has the responsibility for verifying the effective implementation of the onsite quality assurance program.
He reports directly to the Corporate Quality Assurance Manager.
The PVNGS Operations QA/QC Manager and his staff, (1) verify that station procedures conform to quality assurance program requirements, (2) audit, monitor, and inspect station activities such as operation,
- repair, maintenance, and modification, (3) verify implementation of the station training, fire protection, inservice inspection, and other
- programs, (4) control nonconforming items, and (5) verify corrective action.
The Corporate Quality Assurance Manager and his staff have the authority,'elineated in writing, to (1) identify quality assurance
- problems, (2) initiate, recommend, or provide solutions through designated
- channels, and (3) verify implementation of solutions.
Disputes which may arise between quality assurance personnel and personnel in other organizations of the applicant which cannot be resolved shall be referred to the next appropriate higher level of management for resolution.
Disputes which cannot be resolved through these levels may ultimately be resolved by the Operations Executive Vice President and Chief Operating Officer.
17.3 ualit Assurance Pro ram As stated in Section 17.2 of this supplement, the applicant has realigned its organizational structure for the quality assurance program.
To reflect this
- change, the first paragraph of Section 17.3 of the SER is replaced by the following paragraph.
The quality assurance program for the operation of PVNGS 1-3 is presented in the applicant's Operations Quality Assurance Criteria Manual, which describes the program by specifying requi rements and assigning responsibilities for implementing activities affecting quality associated with the operation of PVNGS 1-3.
Nuclear Projects Management, Corporate Quality Assurance, the PVNGS staff, and other groups within the applicant's organization that perform quality-related functions are requi red to develop and implement administrative procedures to prescribe the preparation, review, approval, control, and revision of instructions, procedures, and drawings.
These procedures include provisions to assure that the instructions, procedures, and drawings are reviewed and approved prior to use.
Palo Verde SSER3 17-3
- 17. 5 0 en ualit Assurance Item In Section 17.5 of the SER, the staff stated that the applicant indicated it had deviated from R.G.
1.37 and R.G.
1.38 regarding allowable impurity levels of tapes, adhesives and inks.
Subsequently, in Amendment No.
9 to the
- FSAR, the applicant eliminated the above deviation from those regulatory guides.
Therefore, this matter has been resolved.
- However, the staff has conducted a further review of the applicant's commitment regarding the accuracy of calibration standards in Section 17.2. 12 of the
- FSAR, as stated in Amendment No.
9 to the FSAR.
As a result of that review, the staff has determined that the commitment is not acceptable.
The staff requires that calibration equipment have an accuracy that is better than (rather than "better than or equal to") the item being calibrated.
Also the ratio of inaccuracies shall be four to one instead of three to one.
The staff requires that the applicant revise its FSAR accordingly or provide justification for its current commitment.
Palo Verde SSER3 17-4
APPENDIX A CONTINUATION OF CHRONOLOGY OF RADIOLOGICAL REVIEW May 3, 1982 May 6, 1982 May 6, 1982 May 11, 1982 May 14, 1982 Letter from applicant transmitting, "Design of Public Warning System for Palo Verde Nuclear Generating Station,"
and letter from FEMA, Region IX, dated February 4 accept-ing this system design Letter from applicant advising of plan to use 1977 Edition through 1978 Addenda of Section XI (or later editions and addenda) of ASME Boiler and Pressure Vessel Code Letter from applicant providing information on electrical power systems Letter to applicant forwarding status report on control room design review Letter from applicant submitting seismic qualification review team checklists May 17, 1982 May 21, 1982 May 24, 1982 June 1,
1982 June 1,
1982 June 8, 1982 June 9,
1982 June 10, 1982 Issuance of Supplement No.
2 to Safety Evaluation Report Letter from applicant forwarding evaluation of study on histori cal sei smi city in Arizona Letter from applicant forwarding Amendment 3 to Lessons Learned Implementation Report Letter from applicant advising of realigning of quality assurance organizational structure Letter from applicant forwarding information concerning compliance with 10 CFR 20, 50 and 100 Meeting with applicant to hear its presentation on emer-gency procedures Generic Letter 82 Transmittal of NUREG-0916 Relative to the Restart of R.
E.
Ginna Nuclear Power Plant Letter from applicant providing information regarding recent discovery of possible fault scarps Palo Verde SSER3 A-1
June ll, 1982 Letter from Battelle forwarding revision to Safety Evaluation Report June ll, 1982 Letter to applicant concerning requirement for alternate shutdown system June 15, 1982 Board Notification 82 Notification of Recently Identi-fied Possible Faults near Palo Verde Site June 15, 1982 June 16, 1982 Letter from applicant transmitting Torrey Pines work plan.
Letter from applicant providing additional information on fault scarps June 16, 1982 Letter from applicant commenting on May ll status report on control room design review June 17, 1982 Letter from applicant concerning cooling capacity of ultimate heat sink June 17, 1982 Generic Letter 82 Reactor Operator and Senior Reactor Operator Examinations June 21, 1982 Letter to applicant transmitting request for additional information regarding geologic features June 22, 1982 Letter to applicant transmitting draft Technical Evaluation Report on Control of Heavy Loads June 22, 1982 June 29, 1982 Board Notification 82 Steam Generator Tube Rupture Letter from applicant concerning functionability of pres-surizer safety valves installed in Palo Verde system June 29, 1982 Meeting with applicant to discuss its quality assurance and design verification programs June 29, 1982 Meeting with applicant to discuss status of completion of construction June 29, 1982 Letter from, applicant advising that response to June ll letter on alternate shutdown system will be provided by September 1
June 30, 1982 July 1, 1982 Letter from applicant concerning deep draft pumps Letter from applicant advising that response to June 21 letter will be provided by July 30 July 2, 1982 Generic Letter - Commission Approved Charter for the Committee to Review Generic Requirements Palo Verde SSER3 A-2
July 6, 1982 Letter to applicant concerning audits to be conducted by the Pump and Valve Operability Review Team (PVORT) and the Seismic qualification Review Team (S(RT)
July 15, 1982 Letter from applicant transmitting information regarding the possible accumulation of hydrogen in containment build-ing reactor drain tank room July 15, 1982 Letter from applicant concerning use of storage tank internal coatings July 19, 1982 Letter to applicant advising of acceptability of the Torrey Pines Technology program plan, as revised, for the independ-ent quality assurance evaluation July 19, 1982 Letter from applicant forwarding completed forms for PVORT audit July 27, 1982 Meeting with Combustion Engineering to discuss its responses to staff questions on the CESEC model July 29, 1982 Letter from applicant transmitting response to question regarding geologic features identified as possible faults at site vicinity August 3-6, 1982 Site audit of pump and valve operability August 6, 1982 Letter from applicant forwarding responses to questions concerning postulated loss of the essential spray pond nozzles August 9, 1982 Board Notification 82 Accident Sequence Precursor Program Report August 11, 1982 Letter from applicant transmitting information on local leak rate testing of certain valves using water in lieu of air or nitrogen August ll, 1982 Letter from applicant advising of fuel load dates for Units 1, 2 and 3:
August 1983, August 1984, and November
- 1985, respectively August 12, 1982 Letter from applicant transmitting supplemental information concerning make-up capability to ultimate heat sink August 16, 1982 August 19, 1982 Submittal of Amendment No.
9 to FSAR Letter from applicant forwarding responses to open items of Pump and Valve Operability Review Team Audit Palo Verde SSER3 A-3
August 23, 1982 August 24, 1982 Letter from applicant transmitting 1981 financial statements Meeting with applicant to hear its appeal of staff position that the damping value for cable trays shall be 15K instead of 20/o August 25, 1982 Letter to applicant advising that information submitted regarding recent discovery of geologic features is sufficient to conclude that scarps are not fault controlled, and author-izing applicant to proceed to complete backfilling and 'restora-tion of the trench excavations August 25, 1982 Board Notification 82 Followup to Board Notification 82-58 Regarding Recently Identified Possible Faults Near Palo Verde Site Palo Verde SSER3 A-4
APPENDIX B PALO VERDE UNIT 1 EVALUATION PRESERVICE INSPECTION)
PRESERVICE INSPECTION REQUIREMENTS OF 10 CFR PART 50, PARAGRAPH 50.55a(g)(3)
(This Appendix was prepared with the technical assistance of DOE contractors from the Pacific Northwest Laboratories.)
I.
INTRODUCTION For nuclear power facilities whose construction permits were issued on or after January 1, 1974, 10 CFR 50.55a(g)(3) specifies that components shall meet the preservice examination requirements set forth in Editions and Addenda of Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code applied to the construction of the particular com-ponent.
The provisions of 10 CFR 50.55a(g)(3) also state that the components (including supports) may meet the requirements set forth in subsequent edi-tions of this Code which are incorporated by reference in 10 CFR 50. 55a(b) subject to the limitations and modifications listed therein.
On November 13,
- 1981, the Arizona Public Service Company submitted the Palo Verde Unit 1 preservice inspection plan based upon the 1974 Edition through the Summer 1975 Addenda of the ASME Code.
Specific written relief from Code requirements was requested and supported by information in letters dated December 29, 1981 and April 6, 1982 pursuant to 10 CFR 50.55a(a)(2)(i).
Therefore, our evaluations to date consist of reviewing the applicant's sub-mittal to the requirements of the 1974 Edition of Section XI through Summer 1975 Addenda and determining if relief from the Code requirements was justified.
As a result of our review of this information, we have determined that certain preservice examinations are impractical and performing these required examina-tions would result in hardships or unusual difficulties without a compensating increase in the level of quality and safety.
Our basis for this conclusion is discussed in the subsequent paragraphs of this report.
II.
TECHNICAL REVIEW CONSIDERATIONS A.
Palo Verde Unit 1 received a construction permit on May 25, 1976.
In accordance with 10 CFR 50.55a, the preservice inspection is based on the 1974 Edition of the ASME Code,Section XI including Addenda through Summer 1975.
The ASME first published rules for inservice inspection in the 1970 Edition of Section XI.
No preservice or inservice inspection requirements existed prior to that date.
Since the plant system design and ordering of long lead time components were well underway by the time the Section XI rules became effec-tive, full compliance with the exact Section XI access and inspectabi lity requirements of the Code are not always practical.
Palo Verde SSER3 B-1
B.
Verification of as-built structural integrity of the primary pressure boundary is not dependent on the Section XI preservice examination.
The applicable construction codes to which the primary pressure boundary was fabricated contain material, design, fabrication examination, and testing requirements which by themselves provide the necessary assurance that the components are capable of performing safely under all operating conditions reviewed in the FSAR and described in the plant design specification.
As a
part of these examinations, all of the primary pressure boundary full pene-tration welds were volumetrically inspected (radiographed) and the system was subjected to hydrostatic pressure tests.
C.
The intent of the preservice examination is to establish a reference or baseline prior to the initial operation of the facility.
The results of subsequent inservice examinations can then be compared to the original con-dition to determine if changes have occurred.
If review of the inservice inspection results shows no change from the original condition, no action is required.
In the case where baseline data are not available, a'll indications must be treated as new indications and evaluated accordingly.
Section XI of the ASME Code contains acceptance standards which may be used as the basis for evaluating the acceptability of such indications.
Therefore, conservative disposition of defects found during inservice inspections can be accomplished even though preservice information is not available.
0.
Other benefits of the preservice examination include providing redundant or alternative volumetric inspection of the primary pressure boundary using a
test method different from that employed during the component fabrication.
Successful performance of a preservice examination also demonstrates that. the welds can be effectively inspected during the subsequent inservice examination using a similar test method.
In the case of Palo Verde Unit 1, a large portion of the ASME Code-required preservice examinations was performed.
We have concluded that failure to perform a 100K preservice examination of the welds identified below wi 11 not significantly affect the assurance of the initial structural integrity.
E.
In some cases where the required preservice examinations were not per-formed to the full extent specified by the applicable ASME Code, we will require that these or supplemental examinations be conducted as part of the inservice inspection program.
We have concluded that requiring these supple-mental examinations to be performed at this time (before plant star tup) would result in hardships or unusual difficulties without a compensating increase in the level. of quality and safety.
The performance of supplemental examinations, such as surface examinations, in areas where volumetric inspection is difficult will be more meaningful aftei a period of operation.
Acceptable preoperational integrity has already been established by similar Section III fabrication examinations.
In cases where parts of the required examination areas cannot be effectively examined because-of a combination of component design or current inspection technique li.mitations, we will continue to evaluate the development of new or improved volumetric examination techniques.
As improvements in these areas are achieved, we will require that these new techniques be made a part of the-inservice examination requirements of those components or welds which received a limited preservice examination.
Palo Verde SSER3 B-2
III.
EVALUATION OF RELIEF REQUESTS The applicant requested relief from specific preservice inspection requirements and provided supporting information in letters dated November 13,
- 1981, December 29, 1981., and,April 6, 1982.
The applicant also requested to. use the requirements of subsequent editions and addenda of the Code that have been evaluated and found to be acceptable.
These requests are identified in Section B of this Appendix.
Based on the information submitted by Arizona Public Service Company and our review of the design,
- geometry, and materials of construction of the components, certain preservice requirements of the ASME Boiler and Pressure Vessel
- Code,Section XI have been determined to be impractical and would result in hard-ships or unusual difficulties without a compensating increase in the level of quality and safety.
Therefore, pursuant to 10 CFR Part 50, paragraph 50.55a(a)(2),
our conclusions that these preservice requirements are impractical are justified as follows:
A.
Primar Reactor Coolant Pum s Ultrasonic Examination PSI Pro ram Cha ter 6
Exce tion 7)
Code Re uirement:
Ultrasonic examination shall be conducted in accordance with the provisions of Appendix I.
Where Appendix I (I-1200) is not applicable, the provisions of Article 5 of Section V shall apply.
Code Relief Re uest:
Relief was requested from using the requirements of Article 5 of Section V for ultrasonic examination of the reactor coolant pumps.
As an alternative, use of Appendix I techniques with 50%-50K sizing is requested.
Reason for Re uest:
With respect to the primary piping and reactor coolant
- pumps,Section XI ultrasonic preservice examinations are required to be con-ducted in accordance with Section XI, Paragraph IWA-2232, which states:
"Ultrasonic examination shall be conducted in accordance with the provisions of Appendix I.
Where Appendix I (I-1200) is not applicable, the provisions of Article 5 of Section V shall apply."
Paragraph I-I200 states:
"The methods are.limited to Class 1 and 2 ferritic vessels, 2-1/2 in.
and over in wall thickness'
Clad vessels are included."
Since the reactor coolant pumps are not vessels,.
the examinations must be'onducted in accordance with Article 5 of Section V.
A program utilizing Appendix, I technique with 50X-50K sizing is superior to what is required by the Code and avoids many of the problems associated with conducting a Section V,
Article 5 examination.
First, the Article 5 examinations must be conducted in accordance with Para-graph T-530, which requires in -subparagraph T-535. 1(d) that a transfer method be utilized which requires a reference reflector (drilled hole or notch) to be provided in the part to be. examined.
It is also required that this reference reflector be removed after examination.
It is therefore obvious that Article 5 Palo Verde SSER3 B-3
addresses production testing and not the concerns of Section XI.
Removal of the reference reflector eliminates any chance of repeatability of subsequent inservice examinations.
The undesirability of including a reference reflector in the primary coolant pump is apparent.
Since the transfer technique could not be utilized in performing examinations to Article 5, an exception in the Code.would have to be taken whether performingexaqinations to Article,5 of Section V or Appendix I of Section XI.
- Secondly, the Article 5 calibration techniques for both angle beam and straight beam examinations (see Figures T-535(a) and T-536(a)) require the calibration to be performed from both sides of the calibration standard, which means that the calibration standard cannot be clad (as is the actual component).
Sec-tion XI, Appendix I requires the calibration block to be clad if the component is clad.
This allows the calibration standard to be more representative.
of the component being examined.
If the applicant desires to use a clad cali-bration standard to perform Article 5 examinations, then an exception to the requirements of Article 5 would have to be taken.
Thirdly, Article 5, paragraph T-535. 1(c)(l) requires that the first point on the DAC curve be no less than a 3/8 vee-path or two (2) inches whichever is less.
The second point of the DAC curve is at 5/8 vee-path.
Section XI, Appendix I examinations utilizes a 1/4T (1/8 vee-path),
1/2T (2/8 vee-path),
3/4T (3/8 vee-path),
and l-l/4T (5/8 vee-path) calibration.
I't is obvious that the Appendix I DAC curve is more representative of the actual behavior of the sound beam in the material.
A similar analysis can be extended to straight beam calibrations.
Finally, Article 5 utilizes a 50K reference level for straight beam exami na-tions while Appendix I utilizes an 80K reference level.
This higher refer ence level allows for increased reliability in reporting and evaluating reflectors.
Staff Evaluation:
The applicant requested relief to perform the examination of the primary coolant:pumps with the same ultrasonic testing procedure that was used to examine the reactor pressure vessel.
Our review has determined that Appendix I of Section XI is an acceptable alternative requirement for preservice examination of the primary coolant pumps.
B.
Relief Re uests Involvin U datin To Later Code Edition The applicant submitted four requests for relief which involved updating examination requirements to the 1977 Edition through Summer 1978 Addenda of Section XI of the ASME Code.
Updating to the requirements of later approved editions and addenda is permitted by 50. 55a(g)(3)(iv).
We have evaluated the relief requests'efined in Table 1 and have determined that the relief requests are acceptable and the examinaton requirements are in accordance with subsequent editions of Section XI referenced by 50. 55a(b).
C.
Branch Pi e Connection Welds Exceedin Six-Inch Diameter Code Re uirement:
Examination Cate or B-J:
Perform a volumetric examination of branch pipe connection welds exceeding six-inch diameter.
The examination area should Palo Verde SSER3 B-4
TABLE 1 Relief Request Examination Identification Category Component B-K-1 C-E-1 C-F C-G C-0 Class 1 welded supports Class 2 welded supports Surface examination of Class 2 piping less than 1/2" wall thickness Class 2 bolting Palo Verde SSER3 B-5
include the weld metal, the base metal for one pipe wall thickness on the main pipe run, and at least 2 inches of base metal along the branch run.
Code Relief Re uest:
Relief was requested from performing 100 percent of the Code-required examina-tion.
Reason for Re uest:
Due to the geometrical configuration of the weld, piping and nozzle, the required material volume will not be 100K examined.
A listing of branch connection welds in this request is included as Table 2.
Dimensioned sketches illustrating the volumes that were not examined are included in the applicant's letter dated April 6, 1982.
A review was performed to establish a supplementary ultrasonic technique or an additional alternative examination and is summarized in Table 3.
The applicant reached the conclusion that the welds were examined to the extent practical.
Staff Evaluation:
We have evaluated the accessibility and inspectabi lity of the subject branch connection welds and have determined that the applicant has examined the welds to the maximum extent practical.
We agree with the basic conclusion of the applicant's review that no other practical techniques could be applied to meet Code requirements.
We have determined that examination of these welds to the extent required by the Code is impractical due to the design of the piping system and/or limita-tions in available examination techniques.
We conclude that the limited Section XI examinations, the volumetric examinations performed during fabrica-tion, and the hydrostatic test demonstrate an acceptable level of preservice structural integrity.
D.
Nozzle to Safe End Weld Safe End to Pi in Welds and Safe End in Branch Pi in Welds Circumferential and Lon itudinal Pi e Welds Branch Pi e
Connection Welds Exceedin Six inch Diameter Lon itudinal Weld Joints in Fittin s and Branch Pi e-To-Pi e Weld Joints (Relief Re uest 5)
Code Re uirement:
Examination Categories B-F, B-J, C-F and C-G:
Ultrasonic examination shall be conducted in accordance with the provisions of Appendix I.
Where Appendix I is not applicable, the provisions of Article 5 of Section V shall apply.
Code Relief Re uest:
Relief was requested to use Appendix III including Supplement 7, of Section XI from the Winter 1975 Addenda in lieu of ASME Code Section V, Article 5 for piping examination.
Palo Verde SSER3 B-6
TABLE 2 Area Designation Description Zone 6
01-006-008 Surge nozzle to pipe weld 01-006-009 Shutdown cooling nozzle-to-pipe weld Zone 7
01-007-008 Zone 8 01-008-017 Zone 9
01-009-008 01-009-009 Shutdown cooling nozzle-to-pipe weld Drain nozzle-to-pipe weld Safety injection nozzle-to-pipe weld Spray nozzle-to-pipe weld Zone 10 01-010-017 Drain nozzle-to-pipe weld Zone 11 01-011-008 01-011-009 Safety injection nozzle-to-pipe weld Spray nozzle-to-pipe weld Zone 12 01-012-017 'rain nozzle-to-pipe weld Zone 13 01-013-008 01-013-009 Zone 14 01-014-017 Zone 15 01-015-008 Safety injection nozzle-to-pipe weld Charging nozzle-to-pipe weld Drain nozzle-to-pipe weld Safety injection nozzle-to-pipe weld Palo Verde SSER3 B-7
TABLE 3 Evaluation of Alternative Examinations Limitation RT Not practical for use in Section XI exams because of loss of sensitivity due to:
- cladding, double wall thickness, orientation of inservice defects, clouding of film due.to existing radiation, etc.
UT l.
Angles other than 45 and 60 a.
30 b
70o a.
The use of <V 30 exam would not improve the amount of the weld or weld required volume that is presently being examined.
While <V 70 exam would provide a small percentage
. of improvement, it would still not address the ma-jority of the area not presently examined.
Addi-tionally, the calibration blocks that are presently in use for primary pipe are not constructed to allow for a 70~ calibration.
2.
The use of full and 1<V exams Full "V" and "1<V" exams are not recommended because of problems caused by the stainless steel cladding.
Examples:
beam dispersion, beam and mode conversion at all angles which would yield an uncalibrated
- beam, passing the <V of beam travel.
Because of the noz-zles, parallel surfaces are not present so beam loca-tion is undeterminable.
3.
Scanning on the radius of the weld Due to the nature of the nozz'le to blended welds and a continuous radius along the nozzle to pipe transi-tion, if not maintained, this condition will cause uncoupling or liftoff of the transducer or wedge and will result in angles other than those calibrated for.
This would pertain to surface conforming fix-tures as well.
4.
Scanning on the barrel of the nozzle While this exam would place a sound beam through more of the required weld volume, it would not increase the amount, of the weld that is examined.
Further angle exams on the barrel side would not result in the desired beam angle with respect to the weld as per appendix of the code.
The calibration standards that are currently in use are not suitable for per-formance of this type of examination.
Palo Verde SSER3 8-8
Reason For Re uest:
Appendix I of ASME Section XI is not applicable to most of those piping welds due to the specified thickness and material limitations.
The use of side drilled holes to establish a distance amplitude correction, as required by ASME Section V,
is not required by ASME Secton XI editions and addenda referenced by 10 CRF 50 that will be used for the Inservice Inspection.
As an alternative procedure, the rules of Appendix III, including supplement 7,,
of the 1974 Edition through the Winter 1975 Addenda will be used for the ultra-sonic examination of piping welds.
The evaluation of indications will comply with the Summer 1975 Addenda of ASME Section XI.
In addition, the procedures will require that any crack-like indication will be recorded and rejected regardless of amplitude.
Staff Evaluation:
Appendix III, 1977 Edition to the Summer 1978 Addenda has been accepted for use by incorporation into 10 CFR 50.55a(b).
Appendix III, Winter 1975 Addenda closely parallels the later Code except that the required examination volume is more conservative in the Winter 1975 Addenda (i.e., Figure IWB-3514.1(a) of Winter 1975 versus Figure IWB-2500-8 of the 1977 Edition).
The base Code that was used at Palo Verde Unit 1, i.e.,
Summer 1975 Addenda, does not specifically provide volumetric inspection methods for welds in piping, but references Article V of Section V.
The provisions of 1975 Addenda of Section V do not specifically address piping welds either, nor does it stipulate recording levels for ultrasonic flaw indications.
Appendix III of Section XI gives specific guid-ance for ultrasonic examination of piping systems.
The applicant's examination procedure requires that any crack-like indication will be recorded and rejected regardless of amplitude.
We have determined that (1) the use of Appendix III of the 1974 Edition of Section XI including Addenda through Winter 1975 and (2) the applicant's supplemental provision for recording and rejecting crack-like indications are acceptable alternatives to the Code requirements.
Appendix III of Section XI is technically acceptable and is referenced in 10 CFR 50.55a(b).
E.
Circumferential and Lon itudinal Pi e Welds with Access Limitations (Relief Re uest 7)
Code Re uirement:
Examination Cate or B-J - The examination areas shall include essentially 100 percent of the longitudinal and circumferential welds and the base metal for one wall thickness beyond the edge of the weld.
Longitudinal welds shall be examined for at least one foot from the intersection with the edge of the circumferential weld selected for examination.
In the case of pipe branch connections, the areas shall include the weld metal, the base metal for one pipe wall thickness beyond the edge of the weld on the main pipe run, and at least 2 inches of the base metal along the branch run.
Palo Verde SSER3
'B-9,
Examination Cate pries C-F and C-G - Volumetric examination of circumferential butt welds and branch connections exceeding 4 inches diameter including the weld metal and base metal for one wall thickness by a sampling procedure defined in IWC-2520.
Code Relief Re uest:
Relief was requested from performing 100 percent of the Code-required examination.
Reason for Re uest:
In cases where component configuration or limited access resulted in the examination of less than 100%%uo of the Code required volume, alternate examination techniques were considered, and if feasible, used.
In a letter date April 6, 1982, the applicant identified the piping system welds with incomplete scans and "one"side" examinations.
For Palo Verde Unit 1, the applicant estimated that approximately 10,500 UT scans had been accomplished on the 2,612 items which were ultrasonically examined.
Approximately 50 additional UT examinations had not been completed on March 12, 1982.
The applicant's summary, consisting of 126 pages, identifies the welds with examination limitations, the data package
- number, drawing reference number, calibration standard, scan angles, specific configuration/limitation and states whether the obstruction is permanent.
In addition, the applicant performed a review of possible alternative techiques, which is summarized in Table 4.
TABLE 4 Possible Alternative Technique Limitations 1.
Use of greater incident angles (70 )
2.
Use of full or l-l/2V scans 3.
Other techniques:
a.
Pitch-catch UT b.
Radiography-review of Section III data a.
May result in surface waves and interpretation difficulties.
b.
Excessive attenuation; low signal/noise ratio.
c.
Marginal improvement.
d.
Calibration difficulties result-ing from too short calibration bl ock.
a.
Not usable with clad back wall.
b.
Not usable with non-parallel walls.
c.
Calibration difficulties result-ing from calibration block that is too short.
d.
Excessive attenuation; too low signal/noise ratio.
Palo Verde SSER3
,8-10
Staff Evaluation:
We have evaluated the accessibility and inspectability of the welds with incom-plete scans and "one-side" examination defined in the applicant's letter'dated April 6, 1982.
We have determined that examination of these welds to the extent required by the Code is impractical due to the design of the piping system and/or limitation of available examinations methods.
Typical examples of the types of limitation are:
A nozzle reinforcement partially covering the weld subject to examination.
A lug partially obstructing the weld subject to examination.
Instrument nozzles partially obstructing the weld subject to examination.
Piping to valve or component welds where examination is possible only from the pipe side of welds.
In some instances, the obstruction inhibiting weld examination is removable to permit inservice inspections.
Our review has determined that the applicant has examined the subject welds to the maximum extent practical.
We conclude that the limited Section XI examina-tion, the volumetric examinations performed during fabr ication, and the hydrosta-tic test demonstrate an acceptable level of preservice structural integrity.
IV.
CONCLUSIONS Based on the foregoing, we have determined, pursuant to 10 CFR 50.55a(g)(3),
that certain Section XI required preservice examinations are impractical, and compliance with the requirements would result in hardships or unusual difficulties without a compensating increase in the level of quality and safety.
Our technical evaluation has not identified any practical method by which the existing Palo Verde Unit 1 can meet all the specific preservice inspection requirements of Section XI of the ASME Code.
Requiring compliance with all the exact Section XI required inspections would delay the startup of the plant in order to redesign a significant number of plant systems, obtain sufficient replacement components, install the new components, and repeat the preservice examination of these components.
Examples of components that would require redesign to meet the specific preservice examination provisions are the reactor
- vessel, primary coolant
- pumps, and a significant number of the piping and component support systems.
Even after the redesign effort, complete compliance with the preservice examination requirements probably could not be achieved.
- However, the as-built structural integrity of the existing primary pressure boundary has already been established by the construction code fabrication examinations.
Based on our review and evaluation, we conclude that the public interest is not served by imposing certain provisions of Section XI of 'the ASME Code that have been determined to be impractical.
Pursuant to 10 CFR 50.55a(a)(2),
we have allowed relief from these requirements which are impractical to implement and would result in hardship or unusual difficulties without a compensating increase in the level of quality and safety.
Palo Verde SSER3 B-ll
APPENDIX C
PRINCIPAL CONTRIBUTORS E.
Licitra J.
Wermi el D. Terao R.
Gonzales H. Lefevre P.
Sobel J.
Spraul B. Turovlin A. Brauner 0.
Chopra R. Giardina M.
Hum K.
Dempsey Project management Auxiliary systems Mechanical engineering Hydrologic engineering Geology Seismology equality assurance Chemical engineering Siting analysis Power systems Power systems Materials engineering Accident evaluation Palo Verde SSER3 C-1
U.S. NUCLEAR REGULATORY COMMISSION NRC FORM 335 BIBLIOGRAPHICDATA SHEET
- 4. TITLE AND SUBTITLE (Add Volume /Vo.,i(appropriate/
Safety Evaluation Report Related to the Operation of Palo Verde Nuclear Genera'ting Station, Units 1, 2 and 3
- 7. AUTHOR(s)
- 1. REPORT NUMBER (Assigned by DDC/
NUREG-0857 Supplement No. 3
- 2. (Leave blank/
- 3. RECIPIENT'S ACCESSION No.
- 5. DATE REPORT COMPLETED
- 9. PERFORMING ORGANIZATION NAME AND MAILINGADDRESS (include Zip Code)
U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Washington, D.C.
20555 MONTH Se tember DATE REPORT ISSUED MONTH
- 6. (Leave blank/
B, (Leave blankJ YEAR 1982 YEAR 1 82 12, SPONSORING ORGANIZATION NAME ANO MAII.INGADDRESS (include Zip Code/
Same as 9. above
- 10. PROJECT/TASK/WORK UNIT No.
- 11. CONTRACT No.
13 TYPE OF REPORT PE RIOO COVE REO (inclusive dates/
15, SUPPLEMENTARY NOTES 14, (Leave olankJ Pertains to Docket Nos.
STN 50-528 STN 50-529 8c STN 50-5 0 IG, ABSTRACT l200 words or less/
Supplement No. 3 to the Safety Evaluation Report for the application filed by Arizona Public Service
- Company, et, al, for licenses to operate the Palo Verde Nuclear Generating Station, Units 1, 2 and 3 (Docket Nos.
STN 50-528/529/530),
located in Maricopa County, Arizona has been prepared by the Office of Nuclear Reactor Regula-tion of the Nuclear Regulatory Commission.
The purpose of this supplement is to update the Safety Evaluation Report by providing (1) the evaluation of additional information submitted by the applicants since Supplement No. 2 was issued, and (2) the evaluation of the matters that the staff had under review when Supplement No.
2 was issued.
- 17. KEY WORDS AND DOCUMENT ANALYSIS 17a. DESCRIPTORS 17b IDENTIFIERS/OPEN ENDED TERMS IB, AVAILABILITYSTATEMENT Unlimit,ed
'vAtl FORM 335 t7 771
- 19. SECURITY CLASS (7his report/
- 20. SECURITY CLASS (Thts page/
Unclassified 21NO. OF PAGES
- 22. PRICE S