ML17310B292
| ML17310B292 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 05/16/1994 |
| From: | Russell W Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML17310B291 | List: |
| References | |
| 2.206, DD-94-04, DD-94-4, NUDOCS 9405250221 | |
| Download: ML17310B292 (32) | |
Text
UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION William T. Russell, Director DD-94-04 In the Hatter of
)
)
ARIZONA PUBLIC SERVICE
- COMPANY,
)
)
)
(Palo Verde Nuclear Generating Station,
)
Units 1, 2,
and 3)
)
Docket Nos.
STN 50-528, STN 50-529, and STN 50-530 (10 CFR 2.206)
DIRECTOR'S DECISION UNDER 10 CFR 2.206 I.
INTRODUCTION On October 23,
- 1992, Thomas J. Saporito, Jr., filed a Petition pursuant to Section 2.206 of Title 10 of the Code of Federal Regulations requesting that the Nuclear Regulatory Commission (NRC) order the immediate shutdown of the Palo Verde Nuclear Generating Station, Units 1, 2,
and 3 (Palo Verde),
and institute a show cause proceeding to modify, suspend, or revoke the operating licenses of the three Palo Verde units.
The requests weve based on alleged problems with the main steam and pressurizer safety valves at Palo Verde and other matters raised in the Petition.
By letter dated December 29, 1992, Petitioner's.request for the immediate shutdown of the Palo Verde units was denied, and receipt of the Petition was acknowledged.
In a supplement to the Petition dated January 4,
1993, Petitioner also requested that NRC take appropriate enforcement action against Arizona Public Service Company (APS or Licensee) and deny the November 13, 1990, license amendment application for an increased setpoint tolerance for the safety valves.
940525022'405%hi'I PDR ADOCK,05000528 0
P.Dffj
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II.
BACKGROUND As a basis for his request, Petitioner stated that the Arizona Public Service Company and the NRC cannot be sure whether the 72 safety valves will operate within their design bases and setpoint tolerances to mitigate an overpressurization event in any of the Palo Verde units.
In support of this assertion, Petitioner presented seven concerns which are summarized as follows:
(1) The November 13,
- 1990, request of APS to amend the Technical Specifications of its operating licenses for Palo Verde Units 1, 2, and 3 to increase the allowable setpoint tolerances for the main steam and pressurizer safety valves was signed by a person who is not technically qualified to make safety commitments for this or any license amendment request; additionally, 56 persons in engineering positions at Palo Verde hold those positions without having a
bachelor of science degree in engineering.
(2) In a March 22, 1991, interoffice memorandum, the Licensee responded to an employee who stated a concern that the amendment request to increase the allowable setpoint tolerance for the safety valves indicates that the peak analyzed pressure for the loss of condenser vacuum transient is 2740.9 pounds per square inch, absolute (psia),
leaving only a 9. 1-psia margin to the safety limit of 2750 psia.
(3) In a December 4,
- 1991, interoffice memorandum NRC staff stated that it was not prudent to entertain the licensee's request to amend its Technical Specifications at this time.
(4)
A 8
June 1992 Condition Report/Disposition Request of APS (CRDR No. 1-2-0139) listed numerous inadequacies in the safety valves, (5)
One of the authors of CRDR No.
1-2-0139 testified to NRC officials that the Licensee falsified documents related to the Licensee's request to amend its Technical Specifications.
(6)
A person told Petitioner that two NRC Office of Investigations investigators told
I I
W,y
that person that they had documents demonstrating that Licensee officials falsified documents related to the Licensee's request to amend its Technical Specifications'.
(7)
On October 8,
- 1991, an engineer employed by the Licensee willfullyviolated a safety-related procedure by intentionally adjusting pressurizer safety valve PSV-574 contrary to the requirements of the procedure.
Mr. Saporito supplemented his Petition by a letter dated January 4,
- 1993, which reiterated his concerns, and also repeated his requests for an immediate shutdown of Palo Verde and a show cause proceeding to modify, suspend, or revoke the operating licenses of Palo Verde Units 1, 2,
and 3.
In addition, Petitioner requested that the NRC take appropriate enforcement action against the Licensee and that the NRC deny the Licensee's November 13, 1990, license amendment request to revise the setpoint tolerances for the safety valves.'II.
DISCUSSION A.
Personnel ualifications.
Petitioner states that the November 13,
- 1990, request of APS to amend the Technical Specifications of its operating licenses for Palo Verde Units 1, 2, and 3 to increase the allowable setpoint tolerances for the main steam and pressurizer safety valves was signed by a person who is not technically qualified to make safety commitments for this or any other license amendment request.
Additionally, the Petitioner asserts that 56 persons at Palo Verde who hold engineering positions have no bachelor of science degree in engineering.
'On May 9,
- 1991, a petition for leave to intervene and a request for hearing filed by Linda Mitchell, et al.
was granted.
(LBP-9-19) 33 NRC 397 (1991).
Petitioners challenged the Licensee's November 13, 1990, license amendment request for increased allowable setpoint tolerance, but later withdrew that challenge, and the proceeding was terminated.
Arizona Public Service Com an (LBP-91-37A) 34 NRC 199 (1991).
I
NRC regulations require that all applications and amendments to applications be signed by the applicant or duly authorized officer thereof under oath or affirmation pursuant to 10 CFR 55 50.30(b) and 50.90.
The NRC does not require that an applicant or duly authorized officer have any particular educational achievements in order to sign a license or license amendment application.
The November 13,
- 1990, amendment application meets applicable NRC requirements for signature.
Accordingly, Petitioner has neither stated a
violation of NRC requirements nor raised a substantial safety concern.
Petitioner is correct that some personnel in engineering positions do not have engineering degrees.
This was a deviation from the commitment stated in the Updated Final Safety Analysis Report (UFSAR), for which the Licensee was issued a formal Notice of Deviation in NRC Inspection Report 50-528/92-43, dated February 26, 1993.
The deviation occurred after the Licensee revised the UFSAR, committing to qualification requirements as specified in job position descriptions (JPDs),
which exceeded the requirements of ANSI 3.1-1978.
The NRC regional staff has reviewed qualifications of personnel hired into engineering positions since the issuance of the Notice of Deviation, and confirmed that one of the four engineering personnel hired did not have a
bachelor of science (BS) degree in engineering as required by the applicable JPD.
The Licensee identified this condition and initiated Condition Report/Di'sposition..Request 9-3-0205 to evaluate the circumstances.
The Licensee determined that the individual's qualifications were certified by an acting supervisor-who did not have authority to deal with personnel
- matters, and that this fact was.not detected through other reviews in 'the hiring process.
The NRC
inspector reviewed the individual's resume and determined that he had a
BS degree in mathematics and adequate experience, and had worked as a contractor in the same job function for which he was hired.
The inspector concluded that the individual had demonstrated, to Licensee management, his competence in the skills required for his zob position.
Additionally, the individual meets the requirements of ANSI 3.1-1978, which does not require a degree for the job position.
The NRC Region V staff also reviewed the qualifications of seventeen of the Licensee's ASME Section XI testing personnel.
Several discrepancies between JPD requirements and actual qualifications were identified.
Three Consulting Engineers/Senior Consulting Engineers lacked Professional Engineer (PE) certifications required by the JPDs.
Eight people lacked BS degrees in engineering required by the JPDs.
However, the Licensee was aware of all these discrepancies.
The NRC i:dentified one discrepancy of which the Licensee was unaware.
The Licensee had'istaken a
BS degree in Engineering Mathematics for a degree in Engineering.
In all cases,
- however, the personnel met the requirements of ANSI 3.1-1978.
In response to the Notice of Deviation, the Licensee initiated an evaluation of JPDs, with the intent of revising them to require qualifications more appropriate to the job-positions.
The Licensee initiated a review of dual career path programs, which had"res'ulted in some people not having PE certifications and engineeri,ng degrees currently required by the JPDs.
On April 29, 1993, the Licensee changed the UFSAR pursuant to 10 CFR 50.59.
The change eliminated references to JPDs, reducing the qualification requirements to those specified in ANSI 3:1-1978.
As
~ result of this change,
I I
the Licensee no longer deviates from the UFSAR commitments (NRC Inspection Report 50-528/93-26, dated July 30, 1993).
Based on the Licensee's action, the NRC staff concluded that this deviation was eliminated.
The allegation does not raise a substantial safety concern or warrant any action beyond that already taken by the NRC.
B.
The Safet Mar in Concern.
Petitioner states that in a Harch 22, 1991, interoffice memorandum, the Licensee responded to an employee's concern that the amendment request to increase the allowable setpoint tolerance for the safety valves indicates that the peak analyzed pressure for the loss of condenser vacuum (LOCV) transient is 2740.9 pounds per square inch, absolute (psia),
leaving only a 9. 1-psia margin to the safety limit of 2750 psia.
On November 13,
- 1990, the Licensee applied for amendments to the operating licenses for the Palo Verde units to, among other things, increase the setpoint tolerances for main steam safety valves from +1 percent to +3 percent and pressurizer safety valves from +1 percent to +3 percent or -1 percent.
In the NRC review of this matter, one of the NRC staff questions to APS related to the potential overall reduction of conservatism in order to meet the required limits for system overpressurization and other acceptance criteria, especially for the LOCV event.
On Hay 27, 1992, the Licensee submitted the following information regarding the conservatism which exists in the analysis to demonstrate that-the maximum allowable-pressure would not be exceeded:
2.
Feedwater and steam flow actually ramp down to zero in about 18 seconds instead of the analyzed
- 0. 1 second.
Safety valves are assumed to open at the +3 percent setpoint
I
tolerance, whereas some are actually expected to open at lower pressures.
3.
There is 30 psi of additional conservatism in the high pressurizer/pressure trip setpoint of 2540 psia.
Also, surveillance tests indicate that this trip response time is less than 0.3 second instead of the assumed 0.5 second.
4.
The analysis does not assume that the pressurizer spray valves open.
5.
The initial pressurizer level in the analysis is conservative compared to the level normally expected.
6.
Nonsafety
- systems, such as the Reactor Power Cutback System and the Steam Bypass Control
- System, are assumed to not operate in the analysis.
7.
The moderator temperature coefficient is assumed most positive in the analysis.
8.
Other conservative conditions regarding the reactor physics parameters in the analysis are:
the least negative fuel temperature coefficient is assumed, bounding generic kinetic parameters are
- used, and the most limiting control rod is assumed to be stuck full out.
The Licensee stated that, with the operating conditions experienced most of the time, the peak pressure for the LOCV would be only 2650.5 psia (as compared to the safety limit of 2750 psia).
The Licensee also stated that the ASHE Code provides assurance of large margin to failure and that its analysis to support the changes is adequate.
The staff agrees that the ASHE Code overpressure safety limit (110 percent of design pressure, 2750 psia) is conservative.
The NRC staff determined that if the Licensee's analysis demonstrated the adequacy
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of the system overpressure protection with acceptably conservative input parameters and analysis methodology, then no minimal margin beyond the
. acceptance criteria is required.
The NRC staff has reviewed the Licensee's analysis methodology and input assumptions and concluded that they are sufficiently conservative (License Amendment Nos. 75, 6i, and 47
, dated Hay 16, 1994).
Thus the Licensee has met the required limits for overpressurization and other acceptance
- criteria, and demonstrated that maximum allowable pressure would not be exceeded.
Petitioner has not raised a substantial safety concern about the proposed amendment to increase safety valve tolerances at Palo Verde.
C.
The NRC Memorandum.
Petitioner states that in a December 4,
- 1991, NRC interoffice memorandum, an NRC staff member stated that it was not prudent to entertain the Licensee's request to amend its Technical Specifications at this time.
This staff recommendation contained in the interoffice memorandum was based primarily on the conclusion that APS had not established a need for the Technical Specification change and the fact that APS was having trouble meeting the
+1 percent tolerance on the safety valves, as evidenced by the number of Licensee Event Reports filed.
The Licensee's stated need for an expanded safety valve tolerance was to reduce the number of Licensee Event Reports submitted that do 'not have safety significance.
The Licensee's valve performance data demonstrated that, with the proposed setpoint
- changes, the number of required Licensee Event Reports would be reduced.
Also, the purpose of the Technical Specification change was not merely to establish a tolerance that would be met, but to provide a reasonable tolerance that was bounded by a safety analysis.
The Licensee's safety analysis, submitted as part of the proposed
- change, dated November 13,
- 1990, was 'found acceptable in 'the staff's safety evaluation.
Additionally, the Licensee has embarked on a special program to try to improve the repeatability of the setpoints on the safety valves.
All valves in all units have been refurbished and setpoints were established by a uniform method in an attempt to have directly comparable data.
The Licensee is currently testing many more valves than required in an attempt to improve performance.
The Licensee is currently resetting out of tolerance values to the tighter +I percent tolerance each time a valve is tested, and will continue this practice, in order to ensure that setpoint drift does not take valves outside the targeted 3 percent tolerances.
The December 4,
1991, staff memorandum also commented that the Licensee used an incorrect analytical model for the pressurizer safety valve (PSV) lift.
In the analysis proposed in the license Amendment the PSVs were assumed to fully open at their setpoints to immediately deliver full rated discharge flow.
Whereas in the UFSAR analyses, the PSVs are modeled to open only to 70 percent open at the setpoint pressure.
The Licensee based this new assumption on test results which show that the valves attain full lift in 0.02 second after starting to open.
The Licensee stated that the maximum additional accumulation in pressure for this delay in lifting would be about 2 psi more than the analysis'esult.
The NRC staff concludes that the modeling of the PSVs to open fully at their setpoints (with the
+3 percent tolerance) is acceptable on the basis of PSV test data.
The previous method used in modeling the PSV performance involved opening the valve to only 70 percent open at the setpoint pressure.
I The proposed method is more nearly a best-estimate modeling technique (i.e.,
within 2 psi of actual expected performance, as discussed above).
Although the previous method is more conservative than that being currently proposed, the NRC staff concludes that the overall conservatism of the analysis assumptions taken together is adequate, and that the analytical model is acceptable.
In addition, the staff memorandum of December 4,
- 1991, noted that with the nominal settings of the HSSVs, the average setpoint of the HSSVs is 3.3 percent above the design pressure of 1255 psig.
The memorandum further comments that with all valve setpoints at 3 percent above the nominal setpoint values, which are the largest values still meeting the proposed T/S criterion, the resulting average setpoint is 1336 psig or 6.4 percent above the design pressure.
The acceptability of the nominal HSSV setpoints is governed by the ASHE Code which requires that at least one of the HSSVs be nominally set at or below the system design pressure.
The Code also requires that the HSSVs limit the maximum system pressure to 110 percent of the design pressure for the limiting design-basis transient.
The acceptability of the tolerance range (i.e., +/-1 percent or +/-3 percent) is governed by the plant Technical Specification and must be supported by an analysis to demonstrate that the appropriate safety limits (i.e.,
110 percent of design pressure) are not exceeded with the maximum allowable HSSV setpoints for the limiting design-basis transient.
The average value of the HSSV setpoints is not required to meet any specific limit in relation=to the design pressure of the system.
The nominal setpoints for the Palo Verde HSSVs are not proposed to be changed in this amendment request and, therefore, continue to meet the above ASME requirement that at least one of the HSSVs be nominally set at or below the system design pressure.
- Further, the Licensee has
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~
demonstrated by analysis that the maximum system pressure is limited to less than 110 percent'f the system design pressure with the maximum allowable HSSV setpoints for the limiting design-basis transient.
Therefore, the above stated comment in the December 4,
1991, staff memorandum does not provide a basis to deny the amendment request.
The NRC staff has reviewed the license amendment application regarding increasing the setpoint tolerances for the safety valves, and determined that the proposed amendment was acceptable in a Safety Evaluation (License Amendment Nos. 75, 61, and 47
, dated Hay 16, 1994).
Accordingly, Petitioner has failed to raise a substantial safety concern, and Petitioner's request that the amendment not be issued is denied.
D.
The Condition Re ort Dis osition Re uest.
Petitioner states that a June 1992 Condition Report/Disposition Request of APS (CRDR No. 1-2-0139) listed numerous inadequacies in the safety valves (i.e.,
blowdown rings out of position, a history of these val.ves having set point drift, and no preventive maintenance performed by the Licensee since 1984),
A Condition Report/Disposition Request (CRDR) is an internal APS report which formally documents a problem and attempts to determine the root cause in order to prevent the problem from recurring.
In this case, the problem that was documented by the CRDR was the failure of 14 out of 20 main steam safety valves and two out of four pressurizer safety valves to perform within the tolerance of
~"
+1 percerit, as required by the Licensee's Technical Specifications.
All of these valves were removed during the Unit 1 refueling outage and sent to Westinghouse Electric Corporation for testing.
In addition, some blowdown rings were found to be incorrectly set.
APS has since instituted a two-person verification system for confirming that the blowdown rings are correctly
positioned, and has satisfied itself that the quality assurance (gA) program at the Westinghouse test facility fully meets the Licensee and NRC requirements with respect to gA.
The matters discussed in CRDR No. 1-2-0139 were reported to the NRC in a
letter dated June 24,
- 1992, which forwarded Licensee Event Report (LER)92-004.
The report was prepared because some of the safety valves were found to be outside the
+1 percent tolerance called for in the Technical Specifications.
However, this report also contained the results of a safety analysis demonstrating that the safety limit on reactor coolant pressure of 2750 psia was still met with the as-found settings of the safety valves, some of which were outside the proposed tolerance of +3 percent.
The NRC does not have specific preventive maintenance requirements for these valves.
However, the NRC does require out-of-tolerance conditions to be corrected when identified.
The Licensee has performed this required corrective maintenance of resetting the valve setpoint when out-of-tolerance conditions existed.
Additionally, the safety valves are receiving a considerable amount of Licensee attention in an effort to improve their performance.
In each case when the safety valves were found to be outside the tolerance
- band, the Licensee conducted an analysis which-demonstrated that overpressure safety limits were not exceeded with the "as-found" settings.
In addition, all safety valves have'een disassembled, inspected, reworked as required, reassembled, and retested, and lift settings have been readjusted during the recent refueling outages on all of the units.
- Thus, the Licensee's current program meets NRC requirements for safety valve testing.
Although there have been numerous problems in the industry in getting these
l I
l valves to lift within a +1 percent tolerance, this's not necessarily a safety concern.
Relaxation of the Technical Specification tolerance has been granted by the NRC to licensees who have demonstrated that safety limits can be met with the
+3 percent tolerance.
Additionally, there are industry efforts under way through the American Society of Hechanical Engineers (ASHE) to change the tolerance band to +3 percent in the ASHE Code, in order to better reflect actual performance, acceptable from a safety perspective, of these valves.
Petitioner does not raise a substantial safety concern regarding inadequacies of the APS safety valves.
E.
Falsified Documents.
Petitioner states that an individual testified to NRC officials that the Licensee falsified documents related to the Licensee's request to amend its Technical Specifications.
Whether falsified documents were submitted in support of the Licensee's license amendment application to change the allowable tolerances for the safety valves is a matter that the NRC resolved before completing action on the APS license amendment application.
The staff made a request for additional information to the Licensee on September 2,
1993, that detailed apparent discrepancies in information submitted by the Licensee in letters dated Hay 27,
- 1992, and Hay 13,
- 1993, and requested the Licensee to provide the test data used to construct its data tables.
The Licensee summarized its test data in a letter r~
~
of November 12, 1993.
Additionally, the Licensee discussed the discrepancies in data between the two previous submittals.
The Licensee did not perform an independent check of its data, and thus performed an inadequate review of its licensing submittals.
There is no persuasive
- evidence, however, that the Licensee falsified the information in order to support the license amendment
l
application.
The revised data (where as-found setpoint settings were changed, e.g.,
from +3 percent to +2 percent) were not exclusively in a single direction, as would be expected if data had been manipulated or falsified to improve results.
The staff reviewed the Licensee's November 12, 1993, letter in conjunction with the license amendment proposal and found that the corrected data did not change the staff's conclusion that the requested increase in setpoint tolerances is acceptable, Accordingly, the NRC staff concludes that the licensee did not falsify data in support of its license amendment request.
F.
The Office of Investi ations Documents.
Petitioner states that a person told him that two Office of Investigations investigators told that person that they had documents demonstrating that Licensee officials falsified documents related to the Licensee's request to amend the Technical Specifications.
The NRC's Office of Investigations in the region neither has in its possession any documents containing evidence that APS officials falsified documents related to the November 13,
- 1990, APS request to amend the Palo Verde Technical Specifications, nor has the named investigators informed anyone that such documents exist.
G.
Safet Valve Not Ad 'usted Correctl Petitioner states that on October 8,
- 1991, an engineer employed by APS willfullyviolated a safety-related procedure by intentionally adjusting a
pressurizer safety valve (designated as PSV-574) contrary to the requirements of the procedure.
The matters raised in this allegation were examined in NRC regional Inspection Report 92-43, dated February 26, 1993.
(PSV-574 is not a pressu'rizer safety valve; it is a main steam safety valve.)
The NRC staff concluded therein
that the test procedure is not clear regarding the limitations on when adjustments to the valve can be made.
Adjusting the lift setpoint after a
single failure during the testing of this valve appeared to be technically satisfactory on October 8,
- 1991, based on a declining trend in test lift settings and with the knowledge that the trend would continue with additional tests.
Statements in the procedure appeared to indicate the need for at least two test failures before adjusting the valve.
- However, another statement appeared to indicate that the two-failure criterion applied only to the first test if it was a failure.
It was the conclusion of the inspection report that the procedure was unclear and not appropriate to the circumstances.
Accordingly, the Licensee was cited in Inspection Report 92-43, for a Severity Level V violation of the quality assurance provisions in Criterion V, "Instructions, Procedures, and Drawings," of Appendix B to 10 CFR Part 50.
Petitioner's allegation was partially substantiated in that a violation of NRC requirements was identified.
However, the reason for the violation was that the procedure was not clear, not a lax attitude on the part of any person conducting the test or any willful failure to conduct appropriate testing.
The Licensee subsequently revised the procedure to clarify the matter.
The allegation does not raise a substantial safety concern and does not warrant any action beyond that already taken by the NRC.
III.
CONCLUSION Petitioner requested that the NRC order the immediate shutdown of all three units at Palo Verde; institute a proceeding to show cause why the operating licenses should not be modified, suspended, or revoked; take appropriate enforcement action against APS; and deny the November 13, 1990, license amendment application.
The institution of a proceeding in response to a request for action under 10 CFR 2.206 is appropriate only when substantial health and safety issues have been raised.
See Consolidated Edison Co. of New York, (Indian Point, 'Units 1, 2 and 3), CLI-75-8, 2
NRC 173, 176 (1975),
and Washin ton Public Power Su 1
S stem (WPPSS Nuclear Project No. 2), DD-84-7, 19 NRC 899, 923 (1984).
I have applied this standard to determine if any action is warranted in response to the matters raised by Petitioner.
Each of the claims or allegations by Petitioner has been reviewed.
The available information is sufficient to conclude that no substantial safety issue has been raised regarding the operation of Palo Verde.
Other claims either could not be substantiated or the NRC has already taken appropriate enforcement
- action, as explained above.
Therefore, I conclude that, for the reasons discussed
- above, no adequate basis exists for granting Petitioner's requests for immediate shutdown of Palo Verde, for instituting a proceeding to show cause why the operating license should not be modified, suspended, or revoked, for taking any enforcement action against APS beyond that already taken by the NRC, or for denial of the license amendment request for an increase in safety valve tolerances.
A copy of this decision will be filed with the Secretary of the Commission for the Commission to review in accordance with 10 CFR 2.206(c).
As provided by this regulation, this decision will constitute the final action of the Commission 25 days after issuance, unless the Commission, on its own motion, institutes a review of the decision within that time.
FOR THE NUCLEAR REGULATORY COMMISSION William T. Russell, Director Office of Nuclear Reactor Regulation Dated at Rockville, Maryland this 16th day of Hay 1994