ML19340B017
| ML19340B017 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 05/08/1974 |
| From: | Abel J COMMONWEALTH EDISON CO. |
| To: | Ziemann D US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 8010170723 | |
| Download: ML19340B017 (2) | |
Text
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Subject:
Dresden Station Unit 1 - Rod Drop Analyses -
AEC Dkt 50-10 i
Dear Mr. Ziemann:
1 The following information is provided in response to your letter to Mr. Byron Lee dated March 5, 1974.
As a result of your letter we reviewed the rod drop analyses for Dresden Unit 1 and on the basis of this review concur that the drop of an out-of-sequence rod would result in energy releases which are considered to be unacceptably large.
The current operating procedures for Dresden Unit 1 are, in our judgement, adequate t'o preclude sele.ction and withdrawal of an out-of-sequence control rod.
In order to be fully responsive to your letter, we have developed possible additional procedural controls which r ce discussed below.
On the basis of Technical Specifications for other f acilities, the following specification appears to be the currently accepted approach to controlling rod selection.
" control rod w1thdrawal sequences shall be established so that the maximum calculated reactivity that could be added by dropout of any one in-sequence control blade will not make the core more than 1.5% Ak supercritical.
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Whenever the reactor is in the startup/ hot standby or run mode below 10% rated thermal power, no control blade shall be moved unless a second independent operator or technical person verifies that the operator at the reactor console is following the established control rod pattern."
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Commonwealth Edison Comp (h. y Mr. D. L. Ziemann 2-May 8, 1974 Since the above specification is standard for most boiling water reactor plants, we would consider acceptable addition of this specification to the Dresden Unit 1 Technical Specifications in final preparation by your staff.
One signed original and 39 copies of this letter are provided for your use.
Very truly yours, J.
S.
Abel Nuclear Licensing Administrator Boiling Water Reactors e
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