ML20085N356
| ML20085N356 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 06/21/1995 |
| From: | Adensam E NRC (Affiliation Not Assigned) |
| To: | TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| Shared Package | |
| ML20085N358 | List: |
| References | |
| NUDOCS 9506300153 | |
| Download: ML20085N356 (6) | |
Text
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7590-01 UNITED STATES OF AMERICA l
NUCLEAR REGULATORY COMMISSION l
In the Matter of
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TEXAS UTILITIES ELECTRIC COMPANY
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Docket No. 50-445
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(Comanche' Peak Steam Electric
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i Station, Unit 1)
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EXEMPTION 4
P I.
l Texas Utilities Electric Company (the licensee) is the holder of Facility Operating License No. NPF-87 for the Comanche Peak Steam Electric Station (CPSES), Unit No. 1.
The license provides, among other things, that the licensee is subject to all rules, regulations, and orders of the Commission now or hereafter in effect.
i The facility consists of a pressurized water reactor at the licensee's site in Somervell County, Texas.
l II.
The Code of Federal Regulations,10 CFR 50.55a(f)(4)(ii), requires that inservice tests to verify operational readiness of pumps and valves, whose function is required for safety, conducted during successive 120-month 1
i intervals must comply with the requirements of the latest edition and addenda i
of Section XI of the ASME Boiler and Pressure Vessel Code incorporated by i
reference in paragraph (b) of 10 CFR 50.55a, twelve months prior to the start of the 120-month interval.
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. i NRC regulations in 10 CFR 50.12(a) provide for specific exemptions from the requirements of the regulation in Part 50 if: (1) the exemption is authorized by law, will not present an undue risk to the public health and safety, and is consistent with the common defense and security; and, (2) special circumstances are present. The regulations in, 10 CFR 50.12(a)(2)(ii) provide that special circumstances are present where application of the regulation in the particular circumstances would not serve j
the underlying purpose of the rule or is not necessary to achieve the underlying purpose of the rule.
The underlying purpose of 10 CFR 50.55a(f)(4)(ii) is to assure that inservice test (IST) programs are routinely updated to conform to advances in the industry in order to assure continued operability of pumps and valves required for safe operation.
III.
Pursuant to 10 CFR 50.12, the licensee requested on March 1, 1994, an exemption from the requirement of 10 CFR 50.55a(f)(4)(ii) which would allow the first periodic 120-month interval revision for the CPSES Unit 1 IST plan to be based on the Unit 2 commercial operation date (August 3, 1993).
The first periodic interval for Unit 1 is currently based on the Unit I commercial operation date (August 13,1990).
The staff had requested additional information to supplement the March 1,1994, letter. The licensee provided the requested information in its letter dated August 12, 1994.
CPSES Unit 1 and Unit 2 began commercial operation approximately three years apart and are therefore on different schedules for periodic IST program revisions.
In order to maintain the consistency of the IST program between
l CPSES Units 1 and 2, the licensee intends to perform future 120-month program revisions for both units coincidently. The licensee proposes to accomplish this by performing all future IST program revisions for both units at 120-month intervals based on the Unit 2 commercial operation date. This would effectively extend the first test interval for Unit 1 from 120 months to approximately 156 months.
At the licensee's request, the NRC staff previously granted permission to use the later approved 1989 edition of American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME)Section XI for the interval i
of inservice testing at CPSES Unit 2 and at the same time granted permission to update the Unit 1 IST program to the use of that same Code.
Effectively, the pumps and valves at CPSES Units 1 and 2 are being tested to the requirements of a later Code edition that might otherwise not be required to be implemented until the year 2000 for Unit 1 and the year 2003 for Unit 2.
The changes to the 1989 edition of ASME Section XI regarding pump and valve testing represent a substantial technical improvement over the 1986 edition not usually found from edition to edition.
Since none of the IST test frequencies are directly tied to the 120-month interval, except for safety and relief valve testing, the test frequencies are unchanged and remain compliant with the committed edition of the code or as modified by approved relief requests. The schedule for safety and relief valves must be maintained on a five-or ten-year frequency; however, this can be accomplished even if both units are placed on a concurrent interval.
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, IV.
i Therefore, based on these considerations, it is unlikely that the IST program for Unit I will not be updated such that there would be an increase in the risk of failure for operational readiness of pumps and valves whose function is required for the safety of Unit 1.
Since the Unit 1 IST was updated to the Code edition required to support the commercial operation of Unit 2 on August 3, 1993, Unit I was effectively updated per 10 CFR l
50.55a(f)(4)(ii) at that time. Thus, using that date as the start of the 120-month interval will achieve the underlying purpose of 10 CFR 50.55a(f)(4)(ii).
However, as noted above, the licensee must maintain the safety and relief valve testing on a 5-and 10-year frequency, in accordance with American National Standards Institute (ANSI)/ASME OM-1, which is referenced in the 1989 edition of ASME Section XI as applicable for testing of safety and relief i
valves.
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Consequently, the Commission concludes that the special circumstances of 10 CFR 50.12(a)(2)(ii) exist in that application of the regulation in this particular circumstance is not necessary to achieve the underlying purpose of the rule.
further, it is advantageous for a facility with two similar units to
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implement an IST program which is consistent between units by testing each unit to the same Code edition and by scheduling 120-month program updates on each unit to coincide. CPSES Units 1 and 2 are similar units and the licensee
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3 has therefore attempted to capture these advantages through the use of one IST program which specifies the same test requirements for both units based on the same Code Edition.
j The advantages. include a significant reduction in the administrative I
effort required in preparing periodic program updates, a corresponding l
reduction in the program review effort by the NRC staff and a reduction in the i
potential for personnel errors in the performance of testing requirements.
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Further, a significant unit difference is eliminated by applying the same Code l
requirements to the testing of both units.
In addition, this exemption I
increases plant safety through simplification and standardization of plant testing procedures, does not present an undue risk to the public health and f
safety, and is consistent with the common defense and security.
l V.
l Accordingly, the Commission has determined that, pursuant to 10 CFR 50.12, this exemption is authorized by law, will not endanger life or property or the common defense and security, and is otherwise in the public interest and that the special circumstances required by 10 CFR 50.12(a)(ii) i are present. Therefore, the Commission hereby grants Texas Utilities Electric Company an exemption from those requirements of 10 CFR 50.55a(f)(4)(ii) such that the CPSES Unit 1, periodic 120-month IST program interval revisions will be based on the Unit 2 commercial operation date (August 3, 1993).
Pursuant to 10 CFR 51.32, the Commission has determined that.the granting of this exemption will have no significant effect on the quality of the human environment (60 FR 32356). This exemption is effective upon issuance.
Dated at Rockville, Maryland, this ' 21st day of June 1995.
FOR THE NUCLEAR REGULATORY COMMISSION Elinor G. Adensam, Acting Director Division of Reactor Projects III/IV I
Office of Nuclear Reactor Regulation I
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