ML20150F372
| ML20150F372 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 07/07/1988 |
| From: | Larson C NORTHERN STATES POWER CO. |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| IEB-88-004, IEB-88-4, NUDOCS 8807180260 | |
| Download: ML20150F372 (5) | |
Text
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7 Northem States Power Company 414 NicofMt MaH Minneapoks, Minnesc:a 55401 Tslephone (612) 330 5500 July 7, 1988 NRC Bulletin 88-04 Director of Nuclear Reactor Regulation U S Nuclear Regulatory Commission t.ttn:
Document Control Desk Washington, DC 20555 PRAIRIE ISiAND NUCLEAR GENEPJTING PLWT Docket Nos. 50-282 License Nos. DPR-42 50 306 DPR-60 1
Initial Response to NRC Bulletin 88-04 In response to NRC Bulletin No. 88-04, "Potential Safety-Related Pump Loss", the following information is provided:
- 1. Bulletin Action Promptly determine whether or not its facility has any safe-ty-related system with a pump and piping system configuration that does not preclude pump-to pump interaction during mini-flow operation and could therefore result in dead-heading of one or more of the pumps.
Responso It has been determined that this facility has no safety-related system with a pump and piping system configuration that does not preclude pump-to-pump interaction.
- 2. Bulletin Action l
If the situation described in item 1 exists, evaluate the I
system for flow division taking into consideration:
l (a) the actual line and component resistances for the as built configuration of the identified system; 8807100260 080707 PDR ADOCK 05000202
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Director of NRR -
Northem States Power Company July 8, 1988.
Page 2 (b)-:the head versus' flow characteristics of the installed pumps, including actual test data for "strong" and "weak" pump flows; (c)-the effect of_ test instrument error and reading error;.and
- (d) the worst case-allowances for deviatior, of pump test parameters as allowed by the American Society of Mechanical Engineers Boiler nnd Pressure Vessel r de (ASME Code) Section o
XI: Paragraph IWP-3100.
Resoonse As stated in the response above, no pump to-pump interaction exists.
- 3. Bullerin ActigD Evaluate the adequacy of the ninimum flow bypass lines for safety related centrifugal pumps with respect to darage resulting from operation and testing in the minim.m flow mode.
This evaluation should include consideration of the cumulative operating hours in the minimum flow mode over the lifetime of the plant and during the postulated accident scenario in-volving the largest time spent in this mode. The evaluation should be based on best current estimates of potential pump damage from opetation of the specific pump models involved, derived from pertinent test data and field experience on pump damage. The evaluation should also include verification from the pump suppliers that current miniflow rata. (or any
)'
proposed modifi>ations to miniflow systems) are sufficient to ensure that there will be no pump damage from low flow operation.
If the test data do not justify the existing canacity of the bypass lines (e.g., if the data do not come from flows comparable to tle current capacity) or if the pump supplier does not verify ti. adequacy of the current miniflow capacity, the licensee she 'd provide a plan to obtain additional test data and/ot modify the miniflow capacity as needed.
Responig i
Evaluation of the adequacy of the minimum flow bypass lines i
for safety-related centrifugal pumps is in progress.
Verification of miniflo-adequacy from pump suppliers has been requested and is extected shortly. We expect to be able to folly respond to this item by September 1, 1988.
7
2 Director of NRR Nodhem States Power Company July 8, 1988 Page 3 4(ai LJ1etin Action Within 60 days of receipt of this bulletin, provide a written response that sume.arizes the problems and the sy:*ams affected.
Response
See above, 4(b). Bulletin Action Identify the short term and long-term modifications to plant operating procedures or hardware that have been or are being implemented to ensure safe plant operations.
Response
Operating procedures will be revised as necessary to place limits on pump flow conditions in accordance with any new recommendations received from the pump vendors.
The need for hardware modificatiens will be evaluated after information f.om the pump vendors is received.
4(c). Bulletir A,lo_D Identify o. appropriate schedule for long-term resolution of any sign'.ficant problems that are identified as a result of this bulletin.
Eryoonse An e%aluation and supplemental response will be made follow-ing receipt of information from pump suppliers.
4(d). Bulletin Action Provide justification for continued operation particularly with regard to General Design Criterion 35 of Appendix A to Title 10 of the Code of Federal Regulations (10 CFR 50),
"Emergency Core Cooling" and 10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling System for Light Water Nuclear Power Reactors."
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'o Direetor of NRR Northem States Power Company July 8, 1988 Page 4
Response
Evaluation of this issue is continuing as described above.
No significant problems have been identified as a result of this Bulletin at this time.
Please contact us if you have any questions related to the ac-tions we have taken in response to NRC Bulletin No. 88-04.
C E La s Vice ? resident Nuclear Cencration c: Reginnal Administrator, Region III, NRC Sr Resident Inspector, NRC NRR P: oj ect Manager, NRC C Char. Toff i
f.' 3 ; q ' i
-UNITED STATES NUCLEAR REGULATORY COMMISSION NORTilERN STATES POLTER COMPANY PRAIRIE ISIAND NUCLEAR GENERATING PLANT DOCKET NOS. 50-282 50 306 RESPONSE TO NRC BULLETIN 88-04 Northern States Power Company, a Minnesota corporation, with this letter is submitting information requested by NRC Bulletin 80-04.
This letter contain,s no restricted or other defense information.
NORTHERN STATES POL' COMPANY By C E Larsod Vice PreshtentMiuclear Generation On this M _ day of
/p ff before me a notary public in and for said Couq6f, pe/sonally appeared C E Larson, Vice President Nuclear Generation, and beiag first duly sworn acknowl-edged that he is authorized to execute this document on behalf of Northern States Power Company, that he knows the contents there-of, and that to the best of his knowledge, information, and be-lief the statements made in it are true and that is is not inter-posed for delay.
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A10Y L KLAPPDttCR NOTARY PUBLIC--WIMESOTA ACKA COUNTY
% Commessi bpres Sept 3,1NI
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