ML19241B923
| ML19241B923 | |
| Person / Time | |
|---|---|
| Site: | Atlantic Nuclear Power Plant  |
| Issue date: | 07/11/1979 |
| From: | Haga P OFFSHORE POWER SYSTEMS (SUBS. OF WESTINGHOUSE ELECTRI |
| To: | Baer R Office of Nuclear Reactor Regulation |
| References | |
| FNP-PAL-039, FNP-PAL-39, NUDOCS 7907250380 | |
| Download: ML19241B923 (1) | |
Text
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FNP-PAL-039 w
Cff shore Power Systems July 11, 1979 Mr. Robert L. Baer, Chief Light Water Reactors Branch No. 2 Division of Project Management U.S. Nuclear Regulatory Commission 7920 Norfolk Avenue Bethesda, Maryland 20852 m a. H m Re:
Docket No. STN 50-437; Effect of Core Ladle on Reactor Cavity Pressure Analysis
Dear Mr. Baer:
In the reactor cavity analyses presented in Section 15.5.3.1 of the Plant Design Report, the net volume in the reactor sump region is 20,900 cubic feet. This is the free volume in elements 79 and 82 of the TMD analyses.
The corresponding reactor sump region volume with the core ladle s calculated to be 20,031 cubic feet.
The differ-ential volume of approximately four percent would have an inconsequential effect upon the previously calculated peak pressure in elements 79 and 82 since the vent areas of 50 ft2 from these elements remain unchanged. The peak pressures of 9 psig in elements 79 and 82 are shown in Table 15.5.3-2A of the Plant Design Report.
The design of the reactor sump region is based upon the containment design pressure of 15 psig plus the water head up to elevation 117 feet developed as a result of a break at the pipe nozzle. This design basis, which results in a pressure of 32 psig at elevation 77 feet in elements 79 and 82, is considerably more conservative than the short term pressure increase from the reactor cavity analyses.
Ver truly yours,
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