ML20115B342
| ML20115B342 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 10/01/1992 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20115B334 | List: |
| References | |
| NUDOCS 9210150407 | |
| Download: ML20115B342 (6) | |
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UNITED STATES E
NUCLEAR REGULATORY COMMISSION o
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WASHINGTON, D.C. 20666 o
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SAF ETY EVALVATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION MLATED TO AMEND!iGT NO.183 TO FACILITY OPERATING LICENSE DPR-57 A_ND AMENDMENT NO.123 TO FACILE _Y_QPERATING LICENSE NPE-5 G ORGIA POWER COMPANY. ET AL.
J EDWIN 1. HATCH NUCLEAR PLANT. UNITS 1 AND 2 DOCKET NOS. 50-321 AND 50-361 6
1.0 INTRODUCTION
By letter dated July 17, 1992, Georgia Power Company, et al. (the licensees),
proposed license amendments to change the Technical Specifications (TS) for the Edwin 1. Hatch Nuclear Plant, Units 1 and 2.
The proposed changes would change several portions of the TS which involve shutdown and refueling operations.
The proposed changes are listed below:
Proposed Chanae 1:
This proposed change will revise the definition of Core Alteration in TS 1.t.
for Unit I and 1.0 for Unit 2.
ProDosed Chance 2:
This proposed change will revise the definitions of Cold Shutdown Condition and Refuel Mode in Unit 1 TS Section 1.0, and the Operational Conditions in Unit 2 TS Table 1.2.
Proposed Chanae 3:
This proposed change will revise the Action statement for the residual heat removal service water (RHRSW) system shutdown cooling mode in Unit 2 TS 3.7.1.1.
fro osed Chance 4:
J This praposed cnange will alter the wording of Unit 2 TS 3.9.3.
This TS currently requires all control rods to be fully inserted during Core Alterations.
The proposed change will require all control rods to be fully inserted when moving fuel assemblies or startup sources in the core, rather than during all Core Alterations.
9210150407 921001 PDR ADOCK 05000321 P
L..",. This proposed change will also revise the wording of the Bases for TS 3.9.3.
The phrase "during CORE ALTERATIONS" is being replaced with the phrase "during fuel or startup source movement."
1roposed Chana ti:
This proposed change will add new Unit 1 TS 3.10.E.3, " Requirements for Withdrawal of a Control Rod in the Cold Shutdown Condition," and new Unit 2 TS 3.10.5, " Single Control Rod Withdrawal - Cold Shutdown," which will permit the withdrawal of a single control rod for testing while in Cold Shutdown (Unit 2 Mode 4) by imposing certain restrictions.
In addition, this proposed changs will add Bases for these new TSs for both units and will include a reference to the new Unit 2 TS 3.10.5 and its Bases in the Unit 2 index. The current Unit 2 TS 3.10.5, "High Pressure Coolant Injection System," is being deleted along with its listing in the index.
Also, the title of Unic 2 TS 3/4 10.2 was changed by Amendment 121 trom " Rod Sequerre Control System" to lod Worth Minimizer," but the corresponding index listing was not changed.
This listing is now being corrected.
2.0 EVMUATION
,P oposed Chanae 1 a.
l This proposed change will revise the definition of Core Alteration in Technical Specification (TS) 1.C for Unit I and 1.0 for Unit 2.
in purpose of the definition of Core Alterations is to identify operations which have the potential for adding positive reactivity to the core while the vessel head is removed and fuel is in the vessel, incore instruments (such as source range monitors, local power range monitors, intermediate range monitors, traversing incore probes, or special movable detectors) are being excluded from this definition because the amount of fissile material contained in the detectors is so small their movement dou not result in any significant change in core reactivity. Therefore, the systems which were previously required to be operable during incore instrument movement can now be made inoperable so that the licensee can perform the required surveillance testing or preventative maintenance.
The NRC staff has reviewed the above change and finds it acceptable.
b.
Proposed Chance 2 This proposed change will revise the definitions of Cold Shutdown Condition and Refuel Mode in Unit 1 IS section 1.0, and the Operational Corditions in Unit 2 TS Table 1.2.
The revision will specify the condition of the head closure bolts corresponding to the Refuel Mode to remove any uncertainty as to exactly when the reactor mode change occurs.
This will help ensure the operability-requirements of the existing mode are met.
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, The addition of " Shutdown" as an allowable mode switch position for the Refuel Mode will preclude confusion by ensuring no undefined condition is entered during the normal evolution of entering the Refuel Mode.
Having the mode switch in Shutdown under these conditions will represent no reduction in safety for the following Pasons:
1)
The reactor manual control system interlocks associated with the
" Shutdown" position are more restrictive than those for the Refuel Mode.
Specifically, with the mode switch in the Refuel position, the one-rod-out interlock allows no more than one control rod to be withdrawn at a time.
However, with the made switch in the Shutdown position, a rod block is enforced at all times so that no control rods may be withdrawn, 2)
TS 3.10. A.1 (TS 3.9.1 for Unit 2) requires the mode switch to be locked in the Refuel position with the refueling interlocks operable during Core Alterations.
The NRC staff has reviewed the above change and finds it acceptable.
Pro. posed Chance 3 c.
r This proposed change will revise the action statement for the residual heat removal service water (RHRSW) system shutdown cooling mode in Unit 2 TS 3.7.1.1.
The licensee stated that the design of the Hatch RHRSW system includes two separate RHRSW subsystems A and B, supporting RHR subsystems A and B, respectively.
Each RHRSW subsystem is comprised of two RHRSW pumps, a flowpath and a heat exchanger for transferring heat from the associated RHR subsystem. RHRSW subsystem A contains RHRSW pumps A and C, and RHRSW subsystem B contains RHRSW pumps B and D.
An additional feature is the ability to crosstie the RHRSW sub:ystems such that the pumps in one RHRSW subsystem can provide flow through the heat exchanger in the other RHRSW subsystem and thereby support the opposite RHR subsystem.
Therefore, the-licensee concluded that the RHRSW system would be capable of supporting the shutdown cooling function of the RHR system ff it contai.ed one operable RHRSW pump and flowpath in the subsystem corresponding to the operable RHR pump.
Based on its review, the staff finds that this change is nonconservative in that it will reduce the redundancy required for the operability of the RHR service water system which presently exists in the limiting condition of operation for Technical' Specification 3.7.1.1.
Therefore, this change is unacceptable and is denied.
d.
Proposed Chanae 4 This proposed change will alter the wording of Unit 2 TS 3.9.3.
This TS originally required all control rods to be fully inserted during Core Alterations.
The proposed change will require all control rods to be fully e
a
. inserted when moving fuel assemblies or startup sources in the core, rather than during all Core Alterations.
This proposed change will also revise the wording of the bases for Specification 3.9.3.
The phrase "during CORE ALTERATIONS" is being replaced with the phrase "during fuel or startup source movement."
When the vessel head is removed, the reactar mode switch will be in either Refuel or Shatdown.
In Refuel, the one-rot-out interlock prevents more than one control rod from being withdrawn at a tv;.e.
In Shutdown, a control rod block is in effect at all times preventing the withdrawal of even a single control rod.
Because TS 3.1.1, Shutdown Margin, requires the core to be subcritical by at least.38% delta k/k at all times with the highest worth control,od withdrawn, the refuel mode switch interlocks will ensure the reactor does not become critical.
Therefore, it is acceptable to allow control rod withdrawal as long as no other Core Alterations are taking place.
The discussion of TS 3.9.3 contained in the bases section is not being changed.
Only the wording is being changed to match the c ding of this TS.
The NRC staff has revie<.ed the above change and finds it acceptable.
e.
Pronosed Chance 5 This proposed change will add new Unit 1 TS 3.10.E.3, " Requirements for Withdrawal of a Control Rod in the Cold Shutdown Condition" and new Unit 2 TS 3.10.5, " Single Control Rod Withdrawal - Cold Shutdown", which will permit the withdrawal of a single control rod for testing while in Cold Shutdown (Unit 2 Mode 4) by imposing certain restrictions, in iddition, this proposed change will add bases for these new " for both u ts and will include a reference to new Unit 2 TS 3.10.5 r cs bases in the Unit 2 index.
The current Unit 2 TS 3.10.5, "High Pres
. Coolant Injection System," is being deleted along with its listing in the index.
Also, the title of Unit 2 TS 3/4 10.2 was changed by Amendment 121 from " Rod Sequence Control System" to " Rod Worth Minimizer," but the corresponding index listing was not changeri.
This listing is now being corrected.
Originally, in Cold Shutdown, the reactor mode switch is in the Shutdown position, and all control rods are inserted and blocked from withdrawal.
Many systems and functions are not required in these conditions due to the installed interlocks associated with the reactor mode switch in the Shutdown position.
Circumstances will arise while in Cold Shutdown, however, which present the need to withdraw a single control rod for various tests (e.g.,
friction tests, control rod timing, and coupling integrity (checks).
Certain situations may also require the removal of a control rod drive (CRD).
This proposed change would allow single control rod withdrawals and possible subsequent removals by-selecting the Refuel position for the reactor mode switch.
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. With the reactor mode switch in the Refuel position, the ar.41yses for control rod withdrawal during refueling are applicaole and, provided the assumptions of these analyses are satisfied in Cold Shutdown, these analyses will bound the consequences of a postulated accident.
Explicit safety analyses in the Final Safety Analysis Report (Section 15.1.13) demonstrate the functioning of the refueling interlocks and adequate Shutdown Margin (SDM) will preclude-unacceptable reactivity excursions.
Refueling interlocks prevent the withdrawal of more than one control rod.
Under these conditions, since only one control rod can be withdrawn, the core l
will always be subtritical even with the highest worth control rod withdrawn since adequate SDM exists.
The original TS 3.1:.5, "High Pressure Coolant Injection System," is being deleted along with its IP ting in the index.
i This TS includes a footnote which states it is only applicable from June 2-9, 1980.
Since this time period has elapsed, this TS is no longer applicable and may be deleted.
The change to the index listing of TS 3/410.2 is strictly an editorial correction.
1 The NRC staff has reviewed the above change and finds it acceptable.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Georgia State official was notified of the proposed issuance of the amendments.
The State official had no comments.
4.0 ENVIRONMENTAL COPilDERATION The amendments change requirements with respect-to installation or use of a l
facility component located within the restricted area as defined in 10 CFR i
Part 20 and change surveillance requirements.
The NRC staff has determined that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure.
The Commission has previously issued a proposed finding that the amendraents involve no significant hazards consideration, and there has been no public comment on such finding (57.FR-34584 dated August 5, 1992).
Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9),
Pursuant to 10 CFR Sl.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
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. 5.0 CONClJSION The Commission has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
K. Jabbour, PDIl-3/NRR z
Date: October 1, 1992 i
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