ML20141K632
| ML20141K632 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 05/27/1997 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20141K629 | List: |
| References | |
| NUDOCS 9705290256 | |
| Download: ML20141K632 (4) | |
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UNITED STATES g
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NUCLEAR REGULATORY COMMISSION l
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- WASHINGTON, D.C. maa mg
- * * * *,o SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION l
RELATED TO INSERVICE TESTING PROGRAM RELIEF RE0 VESTS FOR ILLIN0IS POWER COMPANY CLINTON POWER STATION i
l DOCKET NUMBER 50-461
1.0 INTRODUCTION
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The Code of Federa7 Regulations, 10 CFR 50.55a, requires that inservice i
testing (IST) of certain American Society of Mechanical Engineers (ASME) Code Class 1, 2, and 3 pumps and valves be performed in accordance with Section XI of the ASME Boiler and Pressure Vessel Code (the Code) and applicable addenda, except where alternatives have been authorized or relief has been requested by the licensee and granted by the Commission pursuant to Sections (a)(3)(i),
(a)(3)(ii), or (f)(6)(1) of 10 CFR 50.55a.
In proposing alternatives or 4
requesting relief, the licensee must demonstrate that:
(1) the proposed alternatives provide an acceptable level of quality and safety; (2) compliance would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety; or (3) conformance is impractical for its l
facility.
Section 50.55a authorizes the Commission to approve alternatives i
and to grant relief from ASME Code requirements upon making the necessary findings.
Guidance related to the development and implementation of IST i
programs is given in Generic Letter (GL) 89-04, " Guidance on Developing l
Acceptable Inservice Testing Programs," issued April 3,1989, and its Supplement 1 issued April 4, 1995. Also see NUREG-1482, " Guidelines for
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Inservice Testing at Nuclear Power Plants," and NUREG/CR-6396, " Examples, Clarifications, and Guidance on Preparing Requests for Relief from Pump and Valve Inservice Testing Requirements."
The 1989 Edition of the ASME Code is the latest edition incorporated by reference in paragraph (b) of Section 50.55a. Subsection IWV of the 1989 Edition, which gives the requirements for IST of valves, references Part 10 of i
the American National Standards Institute /ASME Operations and #aintenance Standards (0M-10) as the rules for IST of valves. OM-10 replaces specific requirements in previous editions of Section XI, Subsection IWV, of the ASME Code. Subsection IWP of the 1989 Edition, which gives the requirements for i
IST of pumps, references Part 6 of the American National Standards Institute /ASME Operations and #afntenance Standanfs (OM-6) as the rules for IST of pumps. OM-6 replaces specific requirements in previous editions of Section XI, Subsection IWP, of the ASME Code.
Illinois Power Company, in a letter dated March 14, 1997, submitted the Clinton' Power Station, second 10-year IST program for pumps and valves. An evaluation of Relief Requests 1201, 3201, and 3202, which were submitted as i
t ENCLOSURE I
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9705290256 970527 PDR ADOCK 05000461 P
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.part of its IST program, is provided below. The licensee's IST program covers the second 10-year IST interval that begins April 24, 1997.
The program was i
developed in accordance with the requirements of the 1989 Edition of the Code.
2.0 RELIEF RE0 VEST 1201 In this relief request, the licensee proposed to use the Clinton Power l
Station, Technical Specification (TS) Surveillance Requirement (SR) 3.0.2, by l
applying the allowable 25% extension to the quarterly test interval for all l
pumps and valves. This proposal is consistent with the NRC's interpretation l
of the Code requirements and a relief request is not required.
As indicated in NUREG 1482, Section 3.1.3, the test intervals specified in the Code may be extended by up to 25% as allowed in the TSs.
However, the test interval l
specified in 0M-10 for safety and relief valves would not be extended other than to coincide with a refueling outage.
This interpretation of the Code is based on the standard TSs, which have been approved by the NRC staff. The extensions apply directly to IST, which is a TS SR.
3.0 RELIEF RE0 VEST 3201 Relief from the requirements of OM-6, paragraph 4.6.5, to measure flow using a rate or quantity meter installed in the pump test circuit, is requested for the diesel fuel oil transfer pumps ID00lPA, B, and C.
3.1 Licensee's Basis For The Relief Reauest The licensee stated the following:
Illinois Power requests relief from the applicable Code requirements i
because the noted pumps do not have a flow rate measuring instrument installed in the pump test circuit.
Installation of the additional instrumentation necessary to comply with the Code would constitute an unnecessary burden for Illinois Power with no appreciable gain in safety.
3.2 Proposed Alternate Testina The licensee proposed the following:
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In light of the impracticality of directly measuring pump flow rates, the following method for determining pump flow rates will be used.
Illinois Power will calculate the flow rate (Q) of the diesel fuel oil j
transfer pumps by dividing the change in level of the diesel fuel day tank by the time the diesel fuel oil transfer pumps are.in operation.
3.3 Evaluation OH-6, paragraph 4.6.5, " Flow Rate Measurement," states, "When measuring flow i
rate, use a rate or quantity meter installed in the pump test circuit.
If a meter does not indicate the flow rate directly, the record shall include the
l method used to reduce the data."
If the licensee determines that the 3
measurement of tank level over the period of test performance meets the requirements for "a rate or quantity meter installed in the pump test circuit," and the test procedure includes the method used to reduce the data for calculation of flow rate, relief is not required.
If these requirements cannot be met, the staff has determined that the use of a tank level to calculate flow rate is an acceptable alternative to the Code, provided the calculated results meet the accuracy requirements of OM-6, ensuring an acceptable level of quality and safety.
3.4 Conclusion The proposed alternative to the Code requirements is authorized pursuant to Section 50.55a(a)(3)(1) based on the alternative providing an acceptable level of quality and safety.
If the licensee determines that the alternative meets the requirements of OM-6, paragraph 4.6.5, this relief request may be deleted, provided the method of reducing the data obtained from the level instrument (s) is included in the test procedure.
4.0 RELIEF RE0 VEST 3202 Relief from the requirements of OM-6, paragraph 4.6.5, to measure flow using a rate or quantity meter installed in the pump test circuit, is requested for the standby liquid control (SLC) pumps IC41-C001A and B.-
i 4.1 Licensee's Basis For The Relief Reauest The licensee stated the following:
Because the flow path for each pump to the reactor is normally isolated via an explosive valve (to be opened in the event of an emergency), pump testing is effected via a flow path to a test tank, for which no flow instrument is installed.
Installation of the additional instrumentation necessary to comply with the Code would constitute an unnecessary burden for Illinois Power with no appreciable gain in safety.
4.2 Prooosed Alternate Testina The licensee proposed the following:
In light of the impracticality of directly measuring pump flow rates, the following method for determining pump flow rates will be used.
Illinois Power will calculate the flow rate (Q) of the SLC pumps by dividing the change in level of the SLC test tank by the time the SLC pump is in operation.
4.3 Evaluation OH-6, paragraph 4.6.5, " Flow Rate Measurement," states, "When measuring flow rate, use a rate or quantity meter installed in the pump test circuit.
If a
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meter does not indicate the flow rate directly, the record shall include the
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method used to reduce the data." If the licensee determines that the measurement of tank level over the period of test performance meets the requirements for "a rate or quantity meter installed in the pump test circuit," and the test procedure includes the method used to reduce the data for calculation of flow rate, relief is not required.
If these requirements cannot be met, the staff has determined that the use of a tank level to calculate flow rate is an acceptable alternative to the Code, provided the calculated results meet the accuracy requirements of OM-6, ensuring an acceptable level of quality and safety.
4.4 Conclusion The proposed alternative to the Code requirements is authorized pursuant to Section 50.55a(a)(3)(1) based on the alternative providing an acceptable level of quality and safety.
If the licensee determines that the alternative meets the requirements of OM-6, paragraph 4.6.5, this relief request may be deleted, provided the method of reducing the data obtained from the level instrument (s) is included in the test procedure.
t0 CONCLUSION Relief Request 1201 is not required since the proposed alternative is consistent with NRC's interpretation of the Code requirements.
Relief Requests 3201 and 3202 are authorized pursuant to 10 CFR 50.55a(a)(3)(i) based on the determination that the alternatives provide an acceptable level of quality and safety.
Principal Contributor:
K. Dempsey Date: hay 27, 1997 1
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