ML21348A126
| ML21348A126 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 12/14/2021 |
| From: | Entergy Operations |
| To: | Thomas Wengert NRC/NRR/DORL/LPL4 |
| Wengert T | |
| References | |
| Download: ML21348A126 (15) | |
Text
Pre-Submittal Meeting for ANO Unit 1 TS 3.4.4, RCS Loops, Modes 1 and 2 License Amendment
1 Agenda Topic Speaker
Introductions
NRC/Entergy Licensee Presentation Entergy Reason for License Amendment Request Proposed Technical Specification Changes Precedent Summary Entergy Questions / Comments NRC Meeting Adjournment
Introductions
NRC / Entergy 2
=
Background===
- Entergy identified that the current methodology for calculating limits with four or three operating RCPs could not be clearly traced to the method originally used to calculate limits with one RCP per loop operating.
- Operational limits for future fuel cycles could not be assured to remain bounded for all conditions.
- The result is a potentially non-conservative TS.
3 Reason for the License Amendment 6)--- 1 --------------..#IV'-/ ----ow E p Ow E R LI F E SM
4 Reason for the License Amendment Background (cont.)
- ANO-1 current Technical Specification (TS) 3.4.4 Reactor Coolant System (RCS) Loops - Modes 1 and 2 Condition A allows power operation with one RCP in operation per loop for 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> without requiring a plant shutdown. This allowance was carried over from the original TS when ANO-1 transitioned to the Improved TS (ITS), which are based on NUREG-1430, Standard Technical Specifications - Babcock and Wilcox Plants Rev. 1.
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1 Reason for the License Amendment 5
Background (cont.)
- NUREG 1430 Rev. 5, TS 3.4.4 does not have a provision that allows for normal power operation with one RCP in operation per loop. It requires the plant to be shutdown and placed in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> if only one RCP is in operation per loop.
1 Reason for the License Amendment 6
Background (cont.)
- Aside from ANO-1, no other operating Babcock and Wilcox plants TS contain a provision that allows for operation with only one RCP in operation per loop.
7 Proposed Amendment
- The proposed amendment will eliminate the current TS 3.4.4 Condition A which allows for one RCP in operation per loop for 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> before requiring the plant to be in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. It will have just one condition which requires the plant to enter Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> if the LCO is not met.
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8 Proposed Amendment Current TS 3.4.4 Condition Required Action Completion Time A. One RCP not in operation in each loop.
A.1 Restore one non-operating RCP to operation 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> B. Required Action and associated Completion Time of Condition A not met.
OR LCO not met for reasons other than Condition A.
B.1 Be in MODE 3.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Proposed TS 3.4.4 Condition Required Action Completion Time A. Requirements of LCO not met.
A.1 Be in MODE 3.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />
9 Proposed Amendment
- The proposed amendment will also lower TS 3.3.1 Reactor Protection System (RPS) Table 3.3.1-1 RPS Instrumentation Function 7 Reactor Coolant Pump to Power Allowable Value from 55% Rated Thermal Power (RTP) with one pump operating in each loop to 5% Rated Thermal Power (RTP) with one pump operating in each loop
- This prevents power operation with only one RCP in operation in each loop and is consistent with NUREG-1430.
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10 Precedent
- No similar amendment requests could be found where a Babcock and Wilcox plant revised TS 3.4.4 (or equivalent) to eliminate the provision to operate with one RCP in operation per loop without requiring a plant shutdown.
- Oconee and Davis Besse current TS require a plant shutdown to Mode 3 (Davis Besse within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, Oconee within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />), which is consistent with NUREG-1430 (within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />).
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11 Precedent
- Davis Besse TS Table 3.3.1-1 for RPS Instrumentation has an Allowable Value of 55.1% RTP with one RCP operating in each RCS loop.
- Oconee's TS Table 3.3.1-1 sets the power-to-pumps trip to ">
2% RTP with 2 pumps operating". The bases for Oconee's lower limit (2% RTP) is " to prevent normal power operation unless at least three RCPs are operating".
- NUREG-1430 TS Table 3.3.1-1 has an Allowable Value of [5]%
RTP with 2 pumps operating.
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12 Summary
- ANO-1 TS 3.4.4 is being treated as a non-conservative TS.
- ANO-1 proposes to revise TS Table 3.3.1-1 and TS 3.4.4 to be consistent with NUREG-1430 Rev. 5.
- None of the operating Babcock and Wilcox plants in the US have a TS condition that allows for extended operation with only one RCP in operation per loop.
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13 Summary
- Submittal to the NRC is currently scheduled for the end of December, 2021.
- Requested approval date is December 30, 2022.
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QUESTIONS?
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