ML20235K196
| ML20235K196 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 07/09/1987 |
| From: | Ridgely J Office of Nuclear Reactor Regulation |
| To: | Wermiel J Office of Nuclear Reactor Regulation |
| References | |
| TAC-61351, NUDOCS 8707160198 | |
| Download: ML20235K196 (1) | |
Text
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July 9 la 1987 0
Docket No. 50-271 NOTE TO: Jared Wermiel, Section Leader Plant Systems Branch Division of Engineering and System Technology J
FROM:
John N. Ridgely, Mechanical Engineer Plant Systems Branch Division of Engineering and Systems Technology
SUBJECT:
TELECON (JUNE 9, 1987) WITH PNL RELATING TO THEIR INDEPENDENT REVIEW 0F THE VERMONT YANKEE REQUEST TO EXPAND THE STORAGE CAPACITY OF THE SPENT FUEL P00L - TAC NUMBER 61351 A conference call was held Between the PNL principle investigator (Carl Wheeler) and the staff (John Ridgely) concerning the status of his independent review of the Vermont Yankee request to expand the storage capacity of the spent fuel pool at 2:20 EDT. The information provided to the staff by the Vermont Yankee licensee in the telcon of this date was provided to the contractor. After some discussion, we concluded that the bundle peaking factor of 1.45 was not an appropriate factor to be used, as it related only to the bundle peaking while in the core and not in the spent fuel pool. The power ratio of the hot bundle to the pool average heat generation rate, as calculated using the equations identified in the notes of the June 9, 1987 conference call, would be 13.9.
The contractor will revise his analysis to use this value.
i The only anticipated " problem" at this time, is the adequacy of the cooling of the spent fuel bundles in a half-doughnut shaped area around each of the spent fuel pool cooling system return lines.
This could affect approximately 12 i
bundles per pool cooling system return line (24 total). The problem is that the water initially goes downward through the bundle until the heat generated
]
by the bundle causes the flow to reverse and overcomes the downward force of the jet. The cycling may only occur for a short period of time and then dampen out. This will be verified by the contractor. One solution is to not store bundles in these locations, but predicting the exact locations is not a simale task. Another solution is to install a baffle on the return line nozzle
--t11s option will be evaluated as part of the present scope of work by the contractor.
The contractor's evaluation of the natural circulation phenomenon, fuel loading patterns, and the effects of the return line is currently anticipated to be complete in August 1987, f,, ) l Afohn N. Ridgely, Mechanical Engineer Plant Systems Branch Division of System Technology Distribution:. Docket]ile' AThadani JCraig VRooney PDR i
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JRi el 1/ /8 8707160198 070709 PDR ADDCK 05000271 p
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