ML030970121

Supplement to Request for Amendment to Technical Specifications Associated with the Refueling Interlocks, Specifications 3/4.10.A & D

ML030970121
Person / Time
Site:	Pilgrim
Issue date:	03/26/2003
From:	Ronald Bellamy Entergy Nuclear Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2.03.038
Download: ML030970121 (14)

Text

Entergy Entergy Nuclear Operations, Inc.

Pilgrim Nuclear Power Station 600 Rocky Hill Road Plymouth, MA 02360 Mike Bellamy Site Vice President March 26, 2003 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001

SUBJECT:

Entergy Nuclear Operations, Inc.

Pilgrim Nuclear Power Station Docket No. 50-293 License No. DPR-35 Supplement to Request for Amendment to Technical Specifications Associated With the Refueling Interlocks, Specifications 3/4.10.A and D

REFERENCE:

LETTER NUMBER:

Entergy letter, Request for Amendment to Technical Specifications Associated With the Refueling Interlccks, Specifications 3/4.10.A and D, dated August 18, 2002 2.03.038

Dear Sir or Madam:

By the Reference Entergy Nuclear Operations, Inc. (Entergy) proposed to amend the Pilgrim Station Operating License, DPR-35. Discussions with the NRC staff have identified changes to the proposed amendment to facilitate review and approval of the requested changes. Attached are the supplementary changes to facilitate the review.

The attached supplementary information does not impact Entergy's conclusion in the Reference that the proposed amendment does not involve a significant hazards consideration.

Please contact Mr. Bryan Ford, Licensing Manager, at (508) 830-8403, if you have any questions or require additional information.

I declare under penalty of perjury that the foregoing is true and correct. Executed on this _26 day of March 2003.

Sincerely, Robert M. Bellamy 203038 AUD \\

Entergy Nuclear Operations, Inc.

Letter Number: 2.03.038 Pilgrim Nuclear Power Station Page 2 Attachments: 1. Discussion of Changes - 1 page

2. Mark-up of Proposed Technical Specification and Bases Changes - 9 pages cc:

Mr. Travis Tate, Project Manager Office of Nuclear Reactor Regulation Mail Stop: 0-8B-1 U.S. Nuclear Regulatory Commission 1 White Flint North 11555 Rockville Pike Rockville, MD 20852 U.S. Nuclear Regulatory Commission Region 1 475 Allendale Road King of Prussia, PA 19406 Senior Resident Inspector Pilgrim Nuclear Power Station Mr. Steve McGrail, Director Mass. Emergency Management Agency 400 Worcester Road Framingham, MA 01702 Mr. Robert Walker Radiation Control Program Executive Offices of Health and Human Services 174 Portland Street, 5th Floor Boston, MA 02114 203038

ATTACHMENT 1 Discussion of Changes 203038

Discussion of Changes The following changes from those proposed in Reference 1 are made in the proposed Technical Specifications:

1. The requirement for the reactor mode switch to be locked in the "Refuel" position is restored to the LCO statements for operability and the proposed surveillance on mode switch position is withdrawn.

The revised requirements are consistent with the current Technical Specification requirements. The proposed wording of the remaining surveillance requirement in Specification 4.1 O.A.2 is also editorially revised for clarity and to reflect the changes.

2. The proposed replacement of the reference to the Refuel position "one-rod-out" interlock in Specification 3.1O.D.1.a with a reference to the "Refueling Interlocks" is revised to instead insert a reference to "position indication." This change does not affect the proposed requirements but is made for clarity in the intent of the allowance.

3. The word "insertable" is removed from the proposed required Action 3.1O.A.2.b. This change makes the proposed requirements more restrictive than those previously proposed in that all control rods in core cells containing one or more fuel assemblies will be required to be inserted.

4. The proposed Bases are revised consistent with the proposed changes and the wording of the second sentence of the proposed Specification 3.1O.A.1 is editorially corrected. - -.

Reference 1 - Entergy letter, Request for Amendment to Technical Specifications Associated With the Refueling Interlocks, Specifications 3/4.1 O.A and D, dated August 18, 2002

ATTACHMENT 2 Mark-up of Proposed Technical Specification and Bases Changes

LIMITING CONDITION FOR OPERATION SURVEILLANCE REOUI=EENTS 3I.10 CORE ALTERATIONS ADnlicabilitv:

Applies to the fuel handling and core reactivity limitations during refueling and core alterations.

Obiective:

To ensure that core reactivity is within the capaoility of the control rods and to prevent criticality during refuelin~g 4.10 CORE ALTERATIONS Annlicabili tv:

Applies to the periodic testing of those interlocks and instrumentation used during refueling and core alterations.

Objective:

To verify the operability of instrumentation and interlocks used in refueling and core alterations.

Specification:

ocks A.

Refueling Interlocks Du core alterations when fuel is in th l the reactor mode Prior to any fuel handling with switch shall be lo zd in the the head off the reactor vessel, "R efuel position and the the refueling interlocks shall be refueling interlocks shall be functionally tested. They shall operable.

ested at weekly intervals

\\ A there r until no longer

______ _reued.

e ll also be tested following aM.

_repair workl associated with the in S.

B.

Core Monitoring B.

Core Monitorinz During core alterations when fuel is in the vessel two SRM's shall be operable, one in the core quadrant where fuel or control rods are being moved and one in an adjacent quadrant.

For an SRK to be considered operable, the followinz conditions shall be satAsrie'z:

Prior to making any alterations to the core the ShRe's shall be functionally tested and checked for neutron response. Thereafter, while recuired to be operable, the SR-M.'s will be checked daily for response.

The SPM shall be --msarzd to the normal operating level.

(Use of sneciall moveable, dunking type detectors during initial fuel loading and major core alterations in place of normal detectors is permissible as long as the detector is connected to the normal SAM circuit.)

Amendment No.

8 3/4.10-1

Insert page 3/4.10-1 A.

Refueling Interlocks

1. During in-vessel fuel movement with equipment associated with the interlocks the refueling equipment interlocks shall be operable with the reactor mode switch locked in the "Refuel" position. If one or more required refueling equipment interlocks are inoperable:

A.

Refuelinq Interlocks

1. Prior to in-vessel fuel movement with equipment associated with the refueling equipment interlocks, the interlocks shall be functionally tested. They shall be tested at weekly intervals thereafter until no longer required.

a. Suspend in-vessel fuel movement with equipment associated with the inoperable interlock(s) immediately.

OR

b. Insert a control rod withdrawal block AND verify all control rods are fully inserted.

2. When the reactor vessel head is removed and any control rod is withdrawn the one-rod-out interlock shall be operable with the reactor mode switch locked in the 'Refuel" position. If the one-rod-out interlock is inoperable:

a. Suspend control rod withdrawal immediately.

2. When the reactor vessel head is removed and any control rod is withdrawn the one-rod-out interlock shall be functionally tested at weekly intervals. The functional test is not required to be performed until 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> following withdrawing a control rod.

AND

b. Initiate action to fully insert all control rods in core cells containing one or more fuel assemblies immediately.

LUMITING CONDITIONS FOR,. OPERATION SURVEILLANCE REOUIPMENTS 3.10 B.

CORE ALTERATIONS (Cant)

Core Monitorine (Cont)

I I

2. The SRM shall have a minimum of 3 cps except as specified in 3 and 4 below.

3. Prior to spiral unloading, the SRMI's shall have an initial count rate oŽ> 3 cps.

During spiral unloading, the count rate on the SRM.'s may drop below 3 cps.

4. During spiral reload, each-control cell shall have at least one assembly with a minimum exposure of 1000 MWD/ST.

C.

Len= Fuel Pool Water Level W.10 CORE ALTERATIONS (Cont)

Core Monitoring (Cont)

Sziral Reload During spiral reload, SRM operability will be verified by using a portable external source every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> until the required amount of fuel is loaded to maintain 3 cps.

As an alternative to the above, up to two fuel assemblies will be loaded in different cells containing control blades around each SRM to obtain the required 3 cps.

Until these assemblies have loaded, the cps requirement is not necessary.

C.

Soent Fuel Pool Water Level Whenever irradiated fuel is storec in the spent fuel pool, the water level shall be recorded daily.

D.

Multirle Control Rod Removal Whenever irradiated fuel is stored in the spent fuel pool, the pool water level shall be maintained at or above 33 feet.

D.

Multiule Control Rod Removal

)

1. Any number of control rods and/or control rod drive mechanisms may be removed from the reactor pressure vessel provided that at least the following requirements are satisfied until all control rods and control rod drive mechanisms are reinstalled and all control rods are fully inserted in the core.

a. The reactor mode switch is operable and locked in the Refuel position

+/- - a i

L~

except that th e

1. Within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to the start of removal of control rods and/or control rod drive mechanisms from the core and/ox reactor pressure vessel and at least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> thereafter until all control rods and control rod drive mechanisms are reinstalled and all control rods are fully inserted in the core, verify that:

a. The reactor mode switch is operable and locked inr the Refuel position be bypassed, as required, for those control rods and/or control rod drive mechanisms to be removed, after the fuel assemblies have been removed as specified below.

I Amendment No. 3 9 7-4 IT-19e 3/4.10-2

// S7I I1/ 4, BASES:

3.10 CORE ALTERATIONS A.

RefuelinZ Interlocks The refueling interlocks are designed to back up procedural core reactivity controls during refueling operations.

The interlocks prevent an inadvertent criticality during refueling operations when the reactivity potential of the o e is being altered.

To minimize the possibility of loading fuel into a cell containing no contro:

rod, it is required that all control rods are fully inserted when fuel is being oaded into the reactor core.

This requirement assures that during refuelrng the refueling interlocks, as designed, will prevent inadvertent criticality.

The refuel\\nmg interlocks reinforce operational procedures that prohibit taki2 the reactor eritical under certain situations encountered during refueling operations by\\vestricting the movement of control rods and the operation of refueling equipment.

The refueling interlocks include circuitry which senses the condition of the refueling equipment and the control rods.

Depending on the sensed condition interlocks are actuated which prevent the movement of the refueling equipmen or withdrawal of control rods (rod block).

Circuitry is provided wnich senses the following ccndt-ions:

1.

All rods inserted.

2.

Refueling platform p sitioned near or over the core.

3.

Refueling platform hoists are fuel-loaded (fuel grapple, frame mounted hoist, monorail mounted hoist).

Fuel grapple not full ut.

5.

Service platform hoist fuel-loaded.

6.

One rod withdrawn.

When the mode switch is in the "Re-fuel" position, interlocks prevent the refueling platform from being moved over the care if a control rod is withdrawn and fuel is on a hoist.

Likewise, itfhe refueling platform is ove the core with fuel on a hoist, control rod motion L blocked by the interlocks.

When the mode switch is in the refuel p\\sition only one control rod can be withdrawn.

The refueling interlocks, in caiomnation with core nuclear design and refueling procedures, limit the probability of an inadvertent criticality. The nuclear characteristics of the core assure that the reactor is subcritical even when the highest worth contrcl rod is fullv withdrawn.

The combination of refueling interlocks for control rods and the refueling platform provide redundant methods of preventing inad=ertent criticality even after procedural violations.

The interlocks an n ciszs provide yet another method of avoiding inadvertent criticality.

Amendment No.

/

B 3/4~.10-l

Insert B 3/4.10-1

1. Refueling Equipment Interlocks BACKGROUND Refueling equipment interlocks restrict the operation of the refueling equipment or the withdrawal of control rods to reinforce unit procedures that prevent the reactor from achieving criticality during refueling. The refueling interlock circuitry senses the conditions of the refueling equipment and the control rods. Depending on the sensed conditions, interlocks are actuated to prevent the operation of the refueling equipment or the withdrawal of control rods.

One channel of instrumentation is provided to sense the position of the refueling platform, the loading of the refueling platform fuel grapple, and the full insertion of all control rods, except control rods withdrawn in accordance with LCO 3.1 O.D or fully inserted and disarmed. Additionally, inputs are provided for the loading of the refueling platform frame mounted hoist, the loading of the refueling platform monorail mounted hoist, the full retraction of the fuel grapple, and the loading of the service platform hoist. With the reactor mode switch in the shutdown or refueling position, the indicated conditions are combined in logic circuits to determine if all restrictions on refueling equipment operations and control rod insertion are satisfied.

A control rod not at its full-in position interrupts power to the refueling equipment and prevents operating the equipment over the reactor core when loaded with a fuel assembly. Conversely, the refueling equipment located over the core and loaded with fuel inserts a control rod withdrawal block in the Control Rod Drive System to prevent withdrawing a control rod.

The refueling platform has two mechanical switches that open before the platform or any of its hoists are physically located over the reactor vessel. All refueling hoists have switches that open when the hoists are loaded with fuel.

The refueling interlocks use these indications to prevent operation of the refueling equipment with fuel loaded over the core whenever any control rod is withdrawn, or to prevent control rod withdrawal whenever fuel loaded refueling equipment is over the core.

To minimize the possibility of loading fuel into a cell containing no control rod, it is required that all control rods are fully inserted when fuel is being loaded into the reactor core. This requirement assures that during refueling the refueling interlocks, as designed, will prevent inadvertent criticality.

APPLICABLE SAFETY ANALYSES A prompt reactivity excursion during refueling could potentially result in fuel failure with subsequent release of radioactive material to the environment. Criticality and, therefore, subsequent prompt reactivity excursions are prevented during the insertion of fuel, provided all control rods are fully inserted during the fuel insertion. The refueling interlocks accomplish this by preventing loading of fuel into the core with any control rod withdrawn or by preventing withdrawal of a rod from the core during fuel loading.

Refueling equipment interlocks satisfy Criterion 3 of 10 CFR 50.36(c)(2)(ii).

Insert B 3/4.10-1 (continued)

SPECIFICATION 3.ib.A.1 REQUIREMENTS To prevent criticality during refueling, the refueling interlocks ensure that fuel assemblies are not loaded with any control rod withdrawn. To prevent these conditions from developing, the all-rods-in, the refueling platform position, the refueling platform fuel grapple fuel loaded, the refueling platform frame mounted hoist fuel loaded, the refueling platform monorail mounted hoist fuel loaded, the refueling platform fuel grapple fully retracted position, and the service platform hoist fuel loaded inputs are required to be operable. These inputs are combined in logic circuits, which provide refueling equipment or control rod blocks to prevent operations that could result in criticality during refueling operations.

The interlocks are required to be operable with the reactor mode switch locked in the "Refuel" position during in-vessel fuel movement with refueling equipment associated with the interlocks.

With one or more of the required refueling equipment interlocks inoperable (does not include the one-rod-out interlock addressed in Specification 3.1O.A.2), the unit must be placed in a condition in which the Specification does not apply or the interlocks are not needed. This can be performed by ensuring fuel assemblies are not moved in the reactor vessel or by ensuring that the control rods are inserted and cannot be withdrawn.

Therefore, 3.1 0.A.1.a requires that in-vessel fuel movement with the affected refueling equipment must be immediately (i.e., in a time frame consistent with safety) suspended. This action ensures that operations are not performed with equipment that would potentially not be blocked from unacceptable operations (e.g., loading fuel into a cell with a control rod withdrawn). Suspension of in-vessel fuel movement shall not preclude completion of movement of a component to a safe position.

Alternately, 3.10.A.1.b requires that a control rod withdrawal block be inserted and that all control rods subsequently verified to be fully inserted. This action ensures that control rods cannot be inappropriately withdrawn because an electrical or hydraulic block to control rod withdrawal is in place. Like 3.10.A.1.a these actions ensure that unacceptable operations are blocked (e.g., loading fuel into a cell with the control rod withdrawn).

Insert B 3/4.10-1 (continued)

2. Refuel Position One-Rod-Out Interlock BACKGROUND The refuel position one-rod-out interlock restricts the movement of control rods to reinforce unit procedures that prevent the reactor from becoming critical during refueling operations. During refueling operations, no more than one control rod is permitted to be withdrawn except as allowed by Specification 3.1 O.D.

The refuel position one-rod-out interlock prevents the selection of a second control rod for movement when any other control rod is not fully inserted. It is a logic circuit that has redundant channels. It uses the all-rods-in signal (from the control rod full-in position indicators) and a rod selection signal (from the Reactor Manual Control System).

APPLICABLE SAFETY ANALYSES A prompt reactivity excursion during refueling could potentially result in fuel failure with subsequent release of radioactive material to the environment.

The refuel position one-rod-out interlock and adequate shutdown margin prevent criticality by preventing withdrawal of more than one control rod. With one control rod withdrawn, the core will remain subcritical, thereby preventing any prompt critical excursion.

The refuel position one-rod-out interlock satisfies Criterion 3 of 10 CFR 50.36(c)(2)(ii).

SPECIFICATION 3.1 0.A.2 REQUIREMENTS To prevent criticality, the refuel position one-rod-out interlock ensures no more than one control rod may be withdrawn. Therefore, the one-rod-out interlock must be operable when any control rod is withdrawn (except as allowed by Specification 3.10.D). The reactor mode switch must be locked in the refuel position to support the operability of the interlock.

With the refueling position one-rod-out interlock inoperable, the refueling interlocks may not be capable of preventing more than one control rod from being withdrawn.

This condition may lead to criticality. Therefore, control rod withdrawal must be immediately suspended, and action must be immediately initiated to fully insert all control rods in core cells containing one or more fuel assemblies. Action must continue until all such control rods are fully inserted. Control rods in core cells containing no fuel assemblies do not affect the reactivity of the core and, therefore, do not have to be inserted.

BASES:

3.10 CORE ALTERATIONS (Cont)

C.

Snent Fuel Pool Water Level To ensure there is adequate water to shield and cool the irradiated fuel assemblies stored in the pool, a minimum pool water level is established The minimum water level of 33 feet is established because it would be a significant change from the normal level (-1 foot) and is well above the level to assure adequate cooling.

D.

Multinle Control Rod Removal These specifications ensure maintenance or repair of control rods or rod drives will be performed under conditions that limit the probability of i

ainadvertent criticality.

The requirement that the fuel assemblies in the cell acontrolled by the control rod be removed from the reactor core before the

.5

• D.Ai can be bypassed ensures withdrawal of another control rod does not Xresult in inadvertent criticality.

Each contro2 rod essentially provides ez reactivity control for the fuel assemblies in the cell associated with the Q' et control rod.

Thus, removal of an entire cell (fuel assemblies plus control z

crod) results in a lower reactivity potential of the core.

BASES:

4.10 CORE AILTERATIONS A.

Refueling Interlocks C

e functional testing of all refueling interlocks before any refueling outage wAlr vide positive indication that the interlocks operate in the siutosor w

k they were designed.

By loading each hoist with a weight equal to the fuel asse-ibz positioning the refueling platform, and I

withdrawing control rods, t e-locks can be subjected to valid operational tests.

Where redundancy is provide in the logic circuitry, tests can be performed to assure that each redundartl-e element can independently perform its functions.

B.

Core Monitorinm Requiring the SRM's to be functionally tested prior to any core alteration ensures the SRM's will be operable at the start of that alteration.

The dailv response check of the SRM'5s ensures their continued operability.

Amendment No.

1 9 T

,-*d, it

/ 'f-.

L U -

SPECIFICATION 4.10.A.1 REQUIREMENTS Performance of a functional test demonstrates that each required refueling equipment interlock will function properly when a simulated or actual signal indicative of a required condition is injected into the logic. A successful test of the required contact(s) of a channel relay may be performed by the verification of the change of state of a single contact of the relay. This clarifies what is an acceptable functional test of a relay. This is acceptable because all of the other required contacts of the relay are verified by other Technical Specifications and non-Technical Specifications tests at least once per refueling interval with applicable extensions.

The function test may be performed by any series of sequential, overlapping, or total channel steps so that the entire channel is tested.

The weekly frequency is based on engineering judgment and is considered adequate in view of other indications of refueling interlocks and their associated input status that are available to unit operations personnel.

SPECIFICATION 4.10.A.2 REQUIREMENTS Performance of a functional test demonstrates the associated refuel position one-rod-out interlock will function properly when a simulated or actual signal indicative of a required condition is injected into the logic. A successful test of the required contact(s) of a channel relay may be performed by the verification of the change of state of a single contact of the relay. This clarifies what is an acceptable functional test of a relay. This is acceptable because all of the other required contacts of the relay are verified by other Technical Specifications and non-Technical Specifications tests at least once per refueling interval with applicable extensions. The functional test may be performed by any series of sequential, overlapping, or total channel steps so that the entire channel is tested. The weekly frequency of testing is considered adequate because of demonstrated circuit reliability, procedural controls on control rod withdrawals, and visual and audible indications available in the control room to alert the operator to control rods not fully inserted. To perform the required testing, if the surveillance is not current, the applicable condition may be required to be entered (i.e., a control rod must be withdrawn from its full-in position). Therefore, 4.1O.A.2 is not required to be performed until 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> after any control rod is withdrawn.