ML19291A085
| ML19291A085 | |
| Person / Time | |
|---|---|
| Site: | Midland |
| Issue date: | 03/12/1979 |
| From: | Newberry S Office of Nuclear Reactor Regulation |
| To: | Ferrell C Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML111090060 | List:
|
| References | |
| FOIA-80-515, FOIA-80-555 NUDOCS 7904070088 | |
| Download: ML19291A085 (1) | |
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MAR 12 579 P'EMORNiDLH FOR:
C. II. Ferrell. Accident Analysis Branch, DSE THRU:
G. R. Mazetis, Section Leader, Reactor Systecs Branch, DSS FRCM:
S. F,tipwberry, Reactor Systems Branch, DSS SUEJECT:
ECCS PASSIVE FAILURE LEAK RATE The Midland FSAR states that a leakage ralue of 30 gpc is conservatively assumed for evaluating ECCS performance; however, the applicant also maintains that a leak rate of 500 ml/ min is suita51y conservative for the purposes of dose analysis. Their bases for this statement are tests performed by the pump seal manufacturer.
Although the test repart referenced by the applicant indicates that seal integrity was maintained for the conditions under which they are tested, we do not concur with their proposal for a seal leakage of 500 ml/ min to serve as the bounding Icak rate for a passive failure following a LOCA (valve ste.r packing or purp seal failure). Our position regarding passive failures is enclosed. Values between 30-50 gpm have previously been accepted by the staff. Accordingly, we believe the 40 gpm proposed by Midland b suitably conservative to demonstrate long-term core cooling.
Ortst**1 *1",a bn Scott F. Pfewberry Reactor Systems Branch Division of Systems Safety
Enclosure:
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