ML19276E834
| ML19276E834 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 03/01/1979 |
| From: | Reid R Office of Nuclear Reactor Regulation |
| To: | Cavanaugh W ARKANSAS POWER & LIGHT CO. |
| References | |
| NUDOCS 7903210377 | |
| Download: ML19276E834 (3) | |
Text
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UNITED STATES
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NUCLEAR REGULATORY CCMMisSICN r
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.e 5 i W ASHINGTON D. C. 20555 i
. March 1, 1979
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50-2'.3 Mr. William Cavanaugh, III Executive Director, Generation and Construction Department Arkansas Power & Light Ccmcany P. O. Box 551 Little Rock, Arkansas 72203
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Dear Mr. Cavanaugh:
By letter dated October 27, 1972 supplemented by Te:ter dated January 3,1979, you proposed certain facility mcdifications at Arkansas Nuclear One - Unit 1 (ANO-1) to mitigate a small creak LOCA, assuming a loss of offsite cower and the failure of cne encineered safeguards bus, without requiring operator action.
The leg "A" high pressure injection (HPI) line would be connected to the "0" leg HPI lines; and the "B" leg HPI line would be. connected to the "C" HPI lines. These cross connect lines would assure delivery to the reactor coolant system the minimum emergency core cooling system (ECCS) flow assuming the limiting single failure occurs simultaneously with a LOCA. Globe valves would be installed downstream of the cross connect lines and these valves would be locked after flow esting in the correct position to provide the proper flow split.
Flow crifices will be used to equalize head loss and to prevent pump run cut.
The flow charac-teristics of the proposed modified HPI system with cross connect lines installed, would be verified during pre operational testing. You have also ccmnitted to implement these proposed modifications and testing during the ANO-1 next refueling outage which is currently scheduled to begin about March.1, 1979.
Uoon completion of the flow testing, the gicae valves will be permanently locked in their correct positions as described in your letter of Fecruary 1, 1979.
Since this will ensure tnat the proper ECCS ficw split is main-tained, no tecnnical specification changes are necessary to rescive tne generic issue of HPSI/L?SI throttle valve surveillance recuirements for ANC-1.
4 7903210377
Mr. William Cavanaugh We have previously concluded that the small break LOCA ar.alyses are acceptably conservative and wholly in confor ance with 10 CFR 50.46 and Apcendix K to Part 50. On the basis of our review of your sucmittals dated October 27, 1978 and January 3,1979, and ycur ccmmit nent to complete the proposed modifications and testing during the next schedt led refueling outage we find the modi;' cations acceptable. We conclude that upon completion of the installation of the modifications and testing to verify attainment of the flow split assumed in the analysis referred to above, the emergency core cooling system for ANO-1 will be consistent with the analysis referred to above and is acceptable as a pernanent solution to the small break LOCA problems.
Sincerely, m
,- Q./
j,l/4 $l' A 22'A' Robert W. Reid, Chief Operating Reactors Branch da Division of Operating Reactors cc:
See next page
Arkansas Power & Lignt Company cc:
Phillip <
aqui re Hour, Molas & Jewell IF,s Tower Building Li ttle Rock, Arkansas 72201 I
Mr. Daniel H. Williams i
Manager, Licensing Arkansas Power & Light Cenpany l
Post Of fice Sox 551 I
Little Rock, Arkansas 72203 fir. John '.. Anderson, Jr.
Plant Superintencent Arkansas Nuclear One Post Of fice Sox 608 Russellville, Arkansas 72801 Mr. Thomas F. 'desterman U. S. Muclear Regulatory Commission P. O. Box 2090 Russelville, Arkansas 72801 Mr. Robert B. Borsum Babcock & Wilcox Nuclear Power Generation Division Suite 420, 7735 Old Gecrgetown Road Bethesda, Maryland 20014 Arkansas Polytechnic College Russellville, Arkansas 72301
.