ML20205F622
| ML20205F622 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 03/29/1999 |
| From: | Geoffrey Edwards PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20205F630 | List: |
| References | |
| NUDOCS 9904060335 | |
| Download: ML20205F622 (9) | |
Text
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l St: tion Support Department A
10 CFR 50.90 W~
l PECO ENERGY reco,,,,, c t
Nuclear Croup Headquarters 1
l 965 Chestertwook Boulevard Wayne, PA 19087-5691 i
March 29,1999 Docket Nos. 50-277 50-278 License Nos. DPR-44 DPR-56 I
U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
Subject:
Peach Bottom Atomic Power Station, Units 2 and 3 License Change Application ECR 99-00352
Dear Sir / Madam:
PECO Energy Company (PECO Energy) hereby submits License Change Application l
ECR 99-00352, in accordance with 10 CFR 50.90, requesting a change to the Peach Bottom Atomic Power Station (PBAPS), Units 2 and 3 Facility Operating Licenses. This proposed change will revise the Technical Specifications (TS) to delete the requirement for the " refuel platform fuel grapple fully retracted position" interlock currently required by Technical Specification Surveillance Requirement 3.9.1.1.
I Information supporting this request is contained in Attachment 1 to this letter, and the i
marked up pages showing the proposed changes to the PBAPS, Units 2 and 3 TS are contained in Attachment 2.
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A copy of this License Change Application, including the reasoned analysis about a no
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significant hazards consideration, is being provided to the appropriate Pennsylvania State l
official in accordance with the requirements of 10 CFR 50.91(b)(1).
i We request that this amendment to the PBAPS, U.t 2 and 3 TS be approved by
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September 15,1999 for PBAPS, Units 2 and 3 in order to support the beginning of the upcoming PBAPS, Unit 3 outage currently sch' olled to begin in early October,1999.
l If you have any questions, please do not hesitate to contact us.
i Ve truly yours.
1 pGarrett D. Edwards Director-Licensing
Enclosures:
Affidavit, Attachment 1 Attachment 2 cc:
H. J. Miller, Administrator, Region I, USNRC A. C. McMurtray, USNRC Senior Re:. ?,i inspector, PBAPS l
R. R. Janati, Commonwealth of Pennsylvania 9904060335 990329 i
PDR ADOCK 05000277 P
PDR L
COMMONWEALTH OF PENNSYLVANIA:
l ss.
COUNTY OF CHESTER J. J. Hagan, being first duly sworn, deposes and says:
1 That he is Vice President of PECO Energy Company; the Applicant herein; that he has read the attached License Change Application ECR 99-00352, for Peach Bottom Facility Operating Licenses DPR-44 and DPR-56, and knows the cor'ents thereof; and that tile statements and matters set forth therein are true and correct to the best of his knowledge, information and belief.
ge 1
ice P eside it i
Subscribed and swom to before me this Mf day of 1999.
(-
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Notary Public Carol A.
m ic22&dE%b
. nn._ _
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l ATTACHMENT 1 PEACH BOTTOM ATOMIC POWER STATION UNITS 2 AND 3 1
Docket Nos. 50-277 50-278 License Nos. DPR-44 DPR-56 LICENSE CHANGE APPLICATION i
ECR 99-00352
" Deletion of the " refuel platform fuel grapple fully retracted position" interlock" Supporting Information - 6 Pages L_
Docket Nos. 50-277 50-278 License Nos. DPR-44 DPR-56 Introduction PECO Energy Company, Licensee under Facility Operating Licenses DPR-44 and DPR-56 for the Peach Bottom Atomic Power Station (PBAPS), Units 2 and 3, requests that the Technical Specifications (TS) contained in Appendix A to the Operating License be amended to delete the requirement for the " refuel platform fuel grapple fully retracted position" interlock currently. required by Technical Specification Surveillance 1
Requirement 3.9.1.1. The TS and Bases pages showing the proposed changes are contained in Attachment 2. This License Change Application provides a discussion and description of the proposed changes, a sa0ty :::: ament of the proposed changes, information supporting a finding of No Signif cant Hazards Consideration, and information supporting an Environmental Assessmed
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Discussion and Description of the Proposed Chanaes Technical Specification Section 3.9.1 (" Refueling Equipment Interlocks") requires that the refueling equipment interlocks be operable during in-vessel fuel movement with equipment associated with the interlocks. The specific refueling equipment interlocks are identified in Surveillance Requirement 3.9.1.1. This Surveillance Requirement requires that a channel functirnal test on each refueling equipment interlock input be performed j
at a frequency of seven (7) days. The proposed change would remove the "mfuel platform fuel grapple fully retracted position" interlock from this Surveillance Requirement. A modification will be performed to remove the " refuel platform fuel grapple fully retracted position" from the plant design.
'The refueling interlocks are active with the mode switch in refuel and reinforce administrative procedures for moving fuel. _ The refueling interlocks monitor the three hoists (main, auxiliary, and rail) on the refuel bridge to determine if they are fuel loaded 4
or if the fuel grapple (located on the main hoist) is in the full up position.- These interlocks tie in to the Reactor Manual Control System (RMCS) and provide interlocks in two ways. First, if there is a control rod withdrawn, and either any of the hoists are i
loaded or the fuel grapple is not in the full up position, the bridge will not move towards the core. This prevents a fuel bundle from being inserted into a core location with a control rod withdrawn thereby preventing the possibility of an inadvertent criticality.
Second, a rod block signal is sent to RMCS if either any of the hoists are fuel loaded, or the fuel grapple is not full up and the bridge is over the core. This prevents a control rod from being withdrawn while fuel is being inserted into the vessel. Fuel handling procedures require that interlocks be verified by observing the rod withdraw permissive light in the control room, and by monitoring the rod block interlock light on the refuel bridge. The proposed modification will consist of removing the fuel grapple full up interlock. The other portions of the refueling bridge interlocks will not be affected by this change. The full up limit switch will continue to stop upward motion of the grapple i
Dockst Nos. 50-277 50-278 License Nos. DPR-44 DPR-56 and still provide full up indication.
Reference to the specific interlock (" refuel platform fuel grapple fully retracted position")
was added to the PBAPS, Units 2 and 3 Technical Specifications as a part of the conversion to the improved Technical Specifications as discussed in -the ' Safety Evaluation Report (letter from J. F. Stolz (U. S. Nuclear Regulatory Commission) to G.
A. Hunger, Jr. (PECO Energy Company), Amendment Nos. 210 and 214, dated August 30, 1995). This' interlock was added to the Improved Technical Specifications a5 i, bracketed plant specific deviation from : NUREG-1433, " Standard Technical Specifications General Electric Plants, BWR/4," dated September 28,1992.
As stated in the Peach Bottom Atomic Power Station (PBAPS), Units 2 and 3, Updated Final Safety Analysis Report, Section 7.6.3, the purpose of the " refuel platform fuel grapple fully retracted position" interlock was as a backup to the " refuel platform fuel grapple, fuel loaded" interlock in the event that the weight of the bottom section of the telescoping boom plus the fuel was less than the preset load which initiated the " refuel platform fuel grapple, fuel loaded" interlock. The main hoist uses a telescoping boom consisting of several sections which are supported by the cable monitored by the load sensor.
As each section of the telescoping boom is deployed fully, its weight is no longer supported by the cable but by the section above it. When the fuel assembly is full'j extended to insert fuel, only the last section is supported when the mast is fully down. The weight seen by the load sensor is therefore the total of the fuel bundle plus any boom sections not fully extended. The weight of a fuel bundle and the bottom section of the boom is more than 600 pounds (this corresponds to the least weight of a fuel loaded hoist). The current setpoint of 550 pounds ensures that the main hoist load switch will provide a rod block. Therefore, the fuel grapple full up interlock is not required. Additionally, the other two hoists on the bridge have the fuel loadr i interlock but do not have the backup full up position' interlock. The interlocks are v,( safety-related. The logic system consists of a single channel, and there is no design basis for using redundant and diverse interlocks to provide the rod block.
This interlock is not included in the Limerick Generating Station (LGS), Units 1 and 2 Technical Specifications er derign. LGS, Units 1 and 2 only monitor for fuel loaded hoists as part of its intr, docks Al. hough a complete industry survey was not performed, one other Boiling Was.%actar was also determined to monitor only for fuel loaded hoists, and does not have a foi up interlock.
This change will allow increased commonality in performing work activities during refueling at both PECO Energy Company facilities (PBAPS and LGS), by having the same refueling interlocks for the platforms at both plants. Additionally, the removal of the fuel grapple full up interlock will reduce personnel radiation exposure by improving the efficiency of Control Rod Drive (CRD) work which occurs underneath the vessel.
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Docket Nos. 50-277 50-278 License Nos. DPR-44 DPR-56 This work is often a critical path activity. Currently, when the CRDs are replaced during an outage, the main hoist (fuel grapple hoist) is used to perform blade guide movements in the vessel. Since the CRDs can not be removed as a result of the rod block associated with the " refuel platform fuel grapple fully retracted position," under vessel work must stop when the main hoist is being used to move blade guides thus impacting personnel radiation and outage critical path times. Prevention of the under vessel work was not the intent of the interlock. The system will still perform its safety function which is to prevent control rod v!ithdrawals during fuel movement and to prevent fuel movements in the core while a control rod is withdrawn.
PECO Energy is requesting approval of the proposed TS and Bases pages contained in for both units.
I Safety Assessment
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This License Change Application will revise the refueling bridge interlocks contained in Surveillance Requirement 3.9.1.1 by removing the'" refuel platform fuel grapple fully retracted position" interlock, which is a redundant and diverse interlock to the " refuel platform fuel grapple, fuel' loaded" interlock. The safety objective of the refueling interlocks, in combination with the refueling procedures, is to prevent an inadvertent criticality during refueling operations. As discussed in the PBAPS, Units 2 and 3 Updated Final Safety Analysis Report (UFSAR), the safety design basis of the refueling interlocks it to ensure that: 1) during fuel movements in or over the reactor core, all 5
control rods are in their fully inserted positions, and 2) not more than one control rod adjacent to fueled cells is withdrawn from its fully inserted position at any time when the reactor is in the refuel mode. During refueling operations, the reactor vessel head is removed, allowing direct access to the core. Refueling operations include the removal of reactor vessel upper internals and the movement of spent and fresh fuel assemblies between the core and the fuel storage pool. The refueling platform, and the equipment handling hoists on the platform are used to accomplish refueling tasks. The refueling interlocks reinforce operating procedures that prohibit inadvertent criticality under certain situations encountered during refueling operations by restricting the movement of control rods and the operation of refueling equipment. The refueling interlocks are active with the mode switch in Refuel and are designed to reinforce administrative procedures for moving fuel.
The refueling interiocks are not used to prevent or to mitigate the fuel handling accident as discussed in the PBAPS, Units 2 and 3, UFSAR, Section 14.6.4 (" Refueling Accident"). The " refuel platform fuel grapple fully retracted position" interlock and the
" refuel platform fuel grapple, fuel loaded" interlock provide rod blocks during fuel I
movement over the core. These interlocks are not assumed as an initial condition in the fuel bundle drop accident. Additionally, the refueling interlocks are not assumed as 3
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l Docket Nos. 50-277 4
50-278 1 icense Nos. DPR-44 j
- an initial condition in the control rod drop accident as discussed in the PBAPS, UFSAR, I
'Section 14.6.2 (" Control Rod Drop Accident"). The control rod drop accident is only analyzed when the reactor is critical and not during refueling operations.
The refueling interlocks associated with the refueling platform provide rod blocks to
- ensure that control rods can not be withdrawn when fuel is being moved over the core
_ (PBAPS, Units 2 and 3, UFSAR Section 14.5.3.3, " Control Rod Removal Error During Refueling"). The interlocks also prevent refueling bridge motion towards the core if a control rod is withdrawn during fuel movements (PBAPS, Units 2 and 3, UFSAR Section 14.5.3.4, " Fuel Assembly insertion Error During Refueling"). These events could lead to an inadvertent criticality during refueling. However, removal of the " refuel platform fuel grapple fully retracted position" interlock, which is a redundant and diverse interlock, will not prevent the remaining interlocks from performing their intended safety functions.
The refueling interlocks are active with the mode switch in refuel, and are designed to
- reinforce administrative procedures for moving fuel.
Information Supportina a Findina of No Sianificant Hazarca Consideration We have concluded that the proposed changes to the PBAPS, Units 2 and 3 TS do not involve a Significant Hazards Consideration.
In support of this determination, an
- evaluation of each of the three (3) standards set forth in 10 CFR 50.92 is provided below.
1.
The proposed TS chanaes do not involve a sianificant increase in the orobability or conseauences of an accident previousiv evaluated.
This change removes a redundant interlock and will not impact the functionality of associated interlocks. The removal of the " refuel platform fuel grapple fully retracted position" refueling interlock will not affect the ability of the remaining refueling interlocks to produce a rod block during fuel moves. The administrative controls in place do not allow control rod withdrawals while fuel is being moved
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or fuel movement while rods are withdrawn. The fuel grapple full up interlock is a redundant and diverse interlock and its removal has no impact on plant safety.
1 The interlock's inter,t, to provide a backup to the load sensor, is not required since the setpoint is currently low enough to provide adequate protection therefore not significantly increasing the probability of an at:ident previously evaluated.
The refueling interlocks are not used to pevent or to mitigm the fuel handling accident as discussed in the PBAPS, Units 2 and 3, Ui bAR, Section 14.6.4
(" Refueling Accident"). The " refuel platform fuel grapple fully retracted position" interlock and the " refuel platform fuel grapple, fuel loaded" interlock both provide rod blocks during fuel movement over the core. Additionally, the refueling 4
p Docket Nos. 50-277 50-278 License Nos. DPR-44 DPR-56 interlocks are not assumed as an initial condition in the control rod drop accident as discussed in the' PBAPS, UFSAR, Section 14.6.2 (" Control _ Rod Drop Accident"). The' control rod drop accident is only analyzed when the reactor is critical and not during refueling operations.
The refueling interlocks associated with the refueling platform provide rod blocks to ensure that control rods can not be withdrawn when fuel is being moved over the core (PBAPS, Units 2 and 3, UFSAR Section 14.5.3.3, " Control Rod Removal Error During Refueling"). 'They are also used to prevent refueling bridge' motion. towards the core if a control rod is withdrawn during fuel J
movements (PBAPS, Units 2 and 3, UFSAR Section 14.5.3.4, " Fuel Assembly insertion Error During Refueling"). These interlocks prevent the possibility of an inadvertent criticality during refueling. However, removal of the " refuel platform 1
fuel grapple fully retracted position" interlock, which is a redundant and diverse interlock, will not prevent the remaining interlocks from performing their intended safety functions. The refueling interlocks are active with the mode switch in refuel, and are only designed to reinforce administrative procedures for moving fuel. Therefore, the proposed TS changes will not involve a significant increase in the probability of an accident previously evaluated.
The fuel or core loading characteristics are not altered by the removal of this interlock. The dose resulting from a potential control rod withdrawal or fuel bundle error event is not increased as a result of eliminating this redundant and diverse interlock. Therefore, the removal of the " refuel platform fuel grapple fully retracted position" interlock will not involve a significant increase in the probability or consequences of an accident previously evaluated.
2.
The orooosed TS chanaes do not c.eate the possibility of a new or different kind of i
accident from any accident previousiv evaluated.
i The refueling interlocks are not accident initiators. Nor will any new failure mode be introduced by the removal of the " refuel platform fuel grapple fully retracted position" interlock. The interlocks are used to reinforce administrative controls which prevent fuel movement over the core with control rods withdrawn and preclude withdrawal of control rods when the fuel is being moved over the core.
The interlock for ensuring the fuel grapple is fully up, is a redundant and diverse interlock since a load sensor determines if the main hoist is loaded with a fuel bundle. This redundant and diverse interlock prevents the withdrawal of a 4
control rod while moving fuel during refueling. The setpoint is low enough to ensure a rod block will be received if the main hoist is being used to move fuel over the core and to prevent movement of the refueling bridge. The remaining refueling interlocks, in combination with the refueling procedures, will still prevent 5
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' Docket Nos. 50-277 50-278 License Nos. DPR-44 DPR-56
- an inadvertent criticality during refueling operations. Fuel handling procedures require that interlocks be verified by observing the rod withdraw permissive light in the control room, and by monitoring the rod block interlock light on the refuel bridge. Therefore,.the proposed TS changes do not create the possibility of a
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new or different. kind of accident from any accident previously evaluated.
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' 3.
.The orooosed TS chanaes do not involve a sianificant reduction in a marain of safety.
This change will not involve a significant reduction in a margin of safety. The
" refuel platform fuel grapple fully retracted position" interlock is redundant and diverse to the " refuel platform fuel grapple, fuel loaded" interlock on the main hoist. The other two hoists on the bridge have the fuelloaded interlock but do not have the backup full up position interlock. The margin of safety of the refueling
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interlocks will not be significantly reduced by this change since redundant interlocks are 'not required (this a nonsafety-related function) and the original justification for using it, a high load weight setpoint, is no longer applicable. The system consists of a single channel, and no current sign basis for using redundant and diverse interlocks to provide the rod block. Additionally, the Reactor Manual Control System.will not be affected by this change.
The system's ability to provide a rod block is not affected by this change.
Information Supportina an Environmental Assessment An environmental assessment is not required for the proposed changes since the proposed changes conform to the criteria for " actions eligible for categorical exclusion" as
-specified in 10 CFR 51.22(c)(9). The proposed changes will have no impact on the
- environment. The proposed changes do not involve a significant hazards consideration as discussed in the preceding section. The proposed changes do not involve a significant change in.the types or significant increase in the amounts of any effluents that may be released offsite.- In addition, the_ proposed changes do not involve a significant increase in individual or cumulative occupational radiation exposure.
1 Conclusion We have concluded that the proposed changes to the PBAPS, Units 2 and 3 TS do not involve a Significant Hazards Consideration.
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