ML20210R350

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Application for Amends to Licenses NPF-11 & NPF-18,allowing Performance of CRDM & Ni Replacement to Not Be Considered Core Alterations During Operational Condition 5,Refueling, While Fuel Is in Reactor Vessel
ML20210R350
Person / Time
Site: LaSalle  Constellation icon.png
Issue date: 08/13/1999
From: Jamie Benjamin
COMMONWEALTH EDISON CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20210R354 List:
References
NUDOCS 9908170091
Download: ML20210R350 (10)
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Text

, - (innnv>nwrakh 14)non Compan) lasalle Generating station M01 North .!lst Road Marwilles. 11. 61,4 619~V' TclMi4.W e'6l August 13,1999 United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 LaSalle County Station, Units 1 and 2 Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374

Subject:

Request for a change to Technical Specifications, " Core Alterations."

In accordance with 10 CFR 50.90, Commonwealth Edison Company (Comed) requests a change to Appendix A, Technical Specifications (TS),

Facility Operating Licenses NPF-11 and NPF-18. The proposed change is to TS Section 1.0, Definitions, Item 1.7, " Core Alteration." Changes to TS sections 3/4.1,3/4.3, and 3/4.9 are correspondingly proposed to reflect the proposed change to Definition 1.7. The proposed change is identical to the Improved Standard Technical Specifications (ISTS) as documented in NUREG-1433, Revision 1, " Standard Technical Specifications, General Electric Plants, BWR/4."

The purpose of this amendment is to allow the performance of control rod drive maintenance and nuclear instrumentation replacement to not be considered core alterations during Operational Condition 5, Refueling, while fuelis in the reactor vessel.

The proposed change is subdivided as follows.

1. Attachment A gives a description and safety analysis of the proposed changes. l
2. Attachment B includes the marked-up Technical Specification pages j l with the proposed changes indicated.

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August 13,1999 U.S. Nuclear Regulatory Commission Page 2  ;

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3. Attachment C describes Comed's evaluation performed in accordance with 10 CFR 50.92(c), which supports a finding of no

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significant hazards consideration.

4. Attachment D provides information supporting an Environmental Assessment.

We are requesting that the proposed changes, if found acceptable, be approved prior to October 11,1999 to support the planned Unit 1 refueling outage scheduled to begin October 23,1999.

The proposed changes have been reviewed by the station Plant Operations Review Committee and the Nuclear Safety Review Board in accordance with station procedures.

Comed is notifying the State of Illinois of this request for amendment by j transmitting a copy of this letter and its attachments to the designated State l Official. j i

Should you have any questions concerning this letter, please contact l Frank A. Spangenberg, Ill, Regulatory Assurance Manager, at l (815) 357-6781, extension 2383.

Respectfully, '

4 h h. c Je njamin Site Vice President LaSalle County Station cc: Regional Administrator - NRC Region lil NRC Senior Resident inspector - LaSalle County Station

E

. August 13,1999 U.S. Nuclear Regul tory Commission P:g3 3 STATE OF ILLINOIS }

COUNTY OF LA SALLE )

IN THE MATTER OF )

C COMMONWEALTH EDISON (COMED) COMPANY )

LASALLE COUNTY STATION UNITS 1 and 2 ) Docket Numbers 50-373 and 50-374

Subject:

Request for a change to Technical Specifications, " Core Alterations."

AFFIDAVIT l

l affirm that the content of this transmittal is true and correct to the best of my knowledge, information and belief.

O// x, L '

res de LaSalle County Station Subscribed and sworn to before me, a Noty' Public in and for the State above named, this /3 - day of On A>2 4 , I99 . My Commission expires on

  • /O-/ , 2000.

OmctAL SEAL DEBRAJ.FEENEY biluAd M,una <

NOTARY PUBUC, STATE OFILuNOIS MY COMMISSION EXPIRES 101-2000 Notary Pubifc

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ATTACHMENT A Proposed Changes to Technical Specifications For LaSalle County Station, Units 1 and 2 Iof7 A.

SUMMARY

OF PROPOSED CHANGES In accordance with 10 CFR 50.90, Commonwealth Edison Company (Comed) requests a change to Appendix Technical Specifications (TS), Facility Operating Licenses NPF-11 and NPF-18. The proposed change is to TS Section 1.0, Definitions, item 1.7," Core q Alteration." The proposed change removes elements that do not significantly effect core reactivity, included in the current definition of Core Alterations. Changes to TS sections 3/4.1, " Reactivity Control Systems," 3/4.3, " Instrumentation," and 3/4.9, " Refueling ,

Operations," are correspondingly proposed to reflect the proposed change to Definition 1.7. The proposed change is identical to the Improved Standard Technical Specifications (ISTS) as documented in NUREG-1433, Revision 1," Standard Technical Specifications, General Electric Plants, BWR/4."

The proposed changes are described in Section E of this Attachment. The marked up TS pages are provided in Attachment B.

H. DESCRIPTION OF THE CURRENT REQUIREMENTS The current definition of Core Alteration in TS Section 1.0, Definitions, item 1.7, follows.

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" CORE ALTERATION shall be the addition, removal, relocation or movement of  !'

fuel, sources, incore instruments or reactivity controls within the reactor pressure vessel with the vessel head removed and fuel in the vessel. Suspension of CORE ALTERATIONS shall not preclude completion of the movement of a component to a safe conservative position."

A core alteration is a specific activity conducted while in Operational Condition 5,

" Refueling," requiring additional controls to be in place. The following requirements are  ;

enforced while performing core alterations.

Shutdown margin as required by TS Section 3/4.1.1," Shutdown Margin," must be maintained while in Operational Condition 5, and core alterations must be suspended if I shutdown margin requirements cannot be met.

Neutron monitoring and manual scram functions provided by the reactor protection system, required by TS Section 3/4.3.1, " Reactor Protection System Instrumentation,"

must be maintained while in Operational Condition 5, core alterations are required to be

ATTACHMENT A Proposed Changes to Technical Specifications For LaSalle County Station, Units I and 2 2 of 7 suspended except for movement of source range monitors (SRMs), intermediate range monitors (IRMs), or special movable detectors, or replacement oflocal power range monitor (LPRM) strings provided SRM instrumentation is operable as required by TS Section 3.9.2," Instrumentation."

TS Section 3.9.1, " Reactor Mode Switch," requires that the reactor mode switch shall be operable and locked in the shutdown or refuel position while in Operational Condition 5.

If the mode switch is locked in " Refuel," core alterations shall not be performed unless the refuel position interlocks are operable. Core alterations are to be suspended if the mode switch conditions cannot be met, or if applicable, the refueling interlocks are inoperable.

Two SRMs are required to be oyrable, with one SRM located in the quadrant where core alterations a:e being performed, and the other SRM located in an adjacent quadrant, per TS Section 3.9.2," Instrumentation." If this condition is not met, all core alterations are

to be suspended, except for movement ofIRM, SRM, or special movable detectors.

TS Section 3.9.3, " Control Rod Position," requires all control rods to be inserted during core alterations, except control rods removed per TS 3.9.10.1," Single Control Rod Removal," and TS 3.9.10.2, " Control Rod Removal."

l TS Section 3.9.5, " Communications," requires that direct communications be maintained between the control room and the refueling platform personnel during core alterations, except for movement ofincore instrumentation and control rods with their normal drive system.

l TS Section 3.9.10.1 and TS Section 3.9.10.2 require that SRMs and the reactor mode I

switch are operable, with adequate shutdown margin demonstrated, and that appropriate I restrictions are placed on control rods prior to the removal of a control rod. l l

C. BASES FOR TIIE CURRENT REQUIREMENTS The requirement for defining a specific activity (i.e., core alterations), in Operational ,

Condition 5 is to ensure additional controls are in place to protect against or mitigate a l reactivity excursion or fuel assembly drop when moving reactivity control elements.

The requirement to demonstrate shutdown margin ensures that the reactor will be j maintained sufficiently suberitical to preclude an inadvertent criticality in the shutdown j condition.

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l ATTACHMENT A Proposed Changes to Technical Specifications For LaSalle County Station, Units 1 and 2 3 of 7 l

The neutron monitoring instrumentation and the associated reactor protection system trips provide protection against a " reactivity excursion."

The requirements related to the reactor mode switch ensure that the restrictions on control rod withdrawal and refueling platfonn movement during refueling are properly activated.

These conditions reinforce the refueling procedures and reduce the probability of inadvertent criticality, damage to the reactor internals and fuel assemblies, and exposure of personnel to excessive radiation.

The requirement that all control rods be inserted during core alterations ensures that fuel will not be loaded into a cell without a control rod.

The requirement for communications capability ensures that refueling platform personnel can be promptly informed of significant changes in facility status or core reactivity conditions during movement of fuel within the reactor pressure vessel.

TS requirements related to removal of control rods ensure that maintenance or repair of control rods is performed under conditions that li: nit the probability ofinadvertent criticality.

D. NEED FOR REVISION OF TIIE REQUIREMENT Comed requests approval of the proposed changes prior to October 11,1999, to support activities associated with the planned Unit 1 eighth refueling outage (i.e., L1 R08) scheduled to begin October 23,1999. We request that the amendment be made effective upon issuance. The purpose of the proposed changes is to allow the performance of control rod drive maintenance and nuclear instrumentation replacement to not be considered core alterations during Operational Condition 5, Refueling, while fuel is in the reactor vessel. ,

The performance of the above described control rod drive and nuclear instrumentation j activities with fuel in the reactor pressure vessel constitute core alterations under the l current TS definition. The proposed change Nrmits these activities to be performed '

while not being considered core alterations. This is expected to produce appreciable savings in outage eritical path.

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ATTACHMENT A Proposed Changes to Technical Specifications For LaSalle County Station, Units 1 and 2 4 of 7 E. DESCRIPTION OF TIIE PROPOSED CliANGES The requested change revises the TS Definition 1.7, CORE ALTERATION as follows.

" CORE ALTERATION shall be the movement of any fuel, sources, or reactivity control components, within the reactor vessel with the vessel head removed and fuel in the vessel. The following exceptions are not considered to be CORE ALTERATIONS: 1

a. Movement of source range monitors, local power range monitors, intennediate range monitors, traversing incore probes, or special movable detectors (including undervessel replacement);
b. Control rod movement, provided there are no fuel assemblies in the associated core cell. 1 Suspension of CORE ALTERATIONS shall not preclude completion of movement of a component to a safe position."

The revised definition correspondingly requires changes to the following Unit I and 2 TS items:

TS Limiting Condition for Operation (LCO) 3.1.1," Shutdown Margin," ACTION c. is l revised by deleting footnote symbol " * " following " CORE ALTERATIONS". Footnote  !

  • !s also deleted in its entirety.

Surveillance Requirement (SR) 4.1.3.2 a.," Control Rod Maximum Scram Insertion Times,"is revised by changing Footnote

Table 3.3.1-1," Reactor Protection System Instrumentation," ACTION 3 is revised by deleting footnote symbol " * " following " CORE ALTERATIONS."

Table 3.3.1-1," Reactor Protection System Instrumentation," ACTION 9 is revised by deleting footnote symbol " * " following " CORE ALTERATIONS."

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F l J

ATTACIIMENT A l Proposed Changes to Technical Specifications For LaSalle County Station, Units 1 and 2 5 of 7 l

l {

Foomote

! deleted in its entirety.

l The ACTION statement ofTS LCO 3.9.2," Instrumentation,"is revised by deleting footnote symbol " ** " from " Core Alterations *." Footnote *

  • is also deleted in its entirety.

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Footnote symbol" * "is deleted from the APPLICABILITY and ACTION statements of TS LCO 3.9.5, Communications," and from SR 4.9.5," Communications." Footnote

  • is also deleted in its entirety.

F. SAFETY ANALYSIS OF THE PROPOSED CHANGES The proposed change to the definition of CORE ALTERATIONS limits the definition of movement to only those components which can affect core reactivity, primarily fuel assemblies and control rods adjacent to loaded fuel assemblies.

The neutron monitoring requirement is applicable at all times while in Operational Condition 5. The proposed change recognizes that the movement of neutron monitoring fission chambers used in boiling water reactors does not significantly effect core reactivity, and places no restrictions on their movement / removal. This is consistent with current TS in that in most cases where core alterations are secured, TS still permits movement ofIRMs, SRMs, and special movable detectors.

In addition, movement or removal of a control rod in a defueled cell will no longer be considered a core alteration since the movement or removal does not significantly impact core reactivity. In accordance with their function as reactivity control components, the requirements of TS Sections 3.9.10.1 and 3.9.10.2, applicable to control rod removal will remain in effect to protect against a reactivity excursion. These TS Sections ensure that maintenance or repair of control rods or control rod drives are performed under conditions that limit the probability ofinadvertent criticality.

LaSalle County Station is planning to perform a core shuffle as opposed to the past practice of a full core offload during the Unit 1 October,1999 refueling outage. The

planned shuffle sequence has the potential to minimize the dose to refuel platform L personnel. Fuel moves and component transfers are conducted in accordance with an I

approved nuclear component transfer list (NCTL). The NCTL is written to ensure that l

ATTACHMENT A Proposed Changes to Technical Specifications For LaSalle County Station, Units 1 and 2 6 of 7 shutdown margin is maintained at all times during core alterations. The NCTL provides adequate controls to ensure that movements are performed safely.

The command and control associated with refueling is not impacted by the proposed change. Direct communications will be maintained between the control room and the refueling platform personnel during core alterations as required by TS Section 3.9.5. The fuel handling supervisor will continue to observe and supervise the removal and replacement of SRM, IRM, and control blades within the reactor pressure vessel.

Provisions to limit potential offsite exposures in the event of significant release of radioactivity from loads transported over irradiated fuel will be maintained. Secondary containment will be implemented and controlled by a station administrative procedure during core alterations and during the movement of control blades over irradiated fuel. ,

Secondary containment consists of a ventilation exhaust system, associated radiation I monitors that isolate secondary containment on high radiation, and the Standby Gas Treatment System that provides a charcoal filter on the ventilation exhaust prior to discharging to the environment.

The proposed changes do not impact the requirements for refueling evolutions associated with shutdown margin, core monitoring, and reactor protection system operability.

Secondary containment is required for core alterations and the transfer ofloads over both the core and the spent fu'l pool in order to mitigate the consequences of potential releases. There are no changes made to assumptions used in accident analysis. The planned core shuffle and associated maintenance activities may be performed safely and without any undue risk to the public, when conducted in accordance with the propcaed i changes. l G. IMPACT ON PREVIOUS SUBMITTALS ,

Comed has reviewed the proposed Operating License Amendment request regarding impact on any previous submittals, and has determined that there is no impact on any outstanding previous submittals.

II. SCIIEDULE REQUIREMENTS Comed requests approval of this amendment prior to October 11,1999, to support activities in the upcoming Unit I refueling outage scheduled to begin October 23,1999.

ATTACHMENT A Proposed Changes to Technical Specifications For LaSalle County Station, Units 1 and 2

, 70f7

I. REFERENCES
1. NUREG-1433, Revision 1," Standard Technical Specifications, General Electric Plants, BWR/4."
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