BECO-85-162, Application for Amend to License DPR-35 Consisting of Proposed Change 85-11,revising Section 3.3.8.3.a Allowing Substitution of Qualified Person for Rod Worth Minimizer at Power Levels Equal to or Less than 20%.Fee Paid

Application for Amend to License DPR-35 Consisting of Proposed Change 85-11,revising Section 3.3.8.3.a Allowing Substitution of Qualified Person for Rod Worth Minimizer at Power Levels Equal to or Less than 20%.Fee Paid

ML20137M566
Person / Time
Site:	Pilgrim
Issue date:	09/09/1985
From:	Oxsen A BOSTON EDISON CO.
To:	Vassallo D Office of Nuclear Reactor Regulation
Shared Package
ML20137M571	List: BECO-85-162, Application for Amend to License DPR-35 Consisting of Proposed Change 85-11,revising Section 3.3.8.3.a Allowing Substitution of Qualified Person for Rod Worth Minimizer at Power Levels Equal to or Less than 20%.Fee Paid ML20137M603
References
BECO-85-162, NUDOCS 8509130274
Download: ML20137M566 (4)

Text

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.o ._ e BOSTON EDISON COMPANY 800 BOvtsTON STREET BOstGN, M AssACHusETTs O2199 September 9, 1985 2c'2'$.'~Ir.o-. 8ECo 85-162 Proposed change 85-11 Mr. Domenic B. Vassallo, Chief Operating Reactors Branch #2 Division of Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D. C. 20555 License DPR-35 Docket 50-293 Proposed Technical Specification Change or, the Rod Horth Minimizer

Dear Sir:

Pursuant to 10CFR50.90, Boston Edison Company hereby proposes the attached modification to Appendix A of Operating License No. DPR-35. This modification revises section 3.3.8.3.a and its Bases which concern the Rod Worth Minimizer (RWM). This change allows the substitution of a quallfled person for the RWM at power levels equal to or less-than 201. of rated thermal power.

Should you require further information on this submittal, please contact us.

Very truly yours, '

PMK/kmc Attachment One original and 39 copies Commonwealth of Massat.husetts)

County of Suffolk )

Then personally appeared before me A. L. Oxsen, who, being duly sworn, did state that he is Vice President - Nuclear Operations of the Boston Edison Company, the applicant herein, and that he is duly authorized to execute and file the submittal contained herein in the name and on behalf of the Boston Edison Company and that the statements in said submittal are true to the best of his knowledge and belief.

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o BOSTON EDISON COMPANY Mr. Domenic B. Vassallo, Chief l

! September 9, 1985 Page 2-cc: Mr. Robert M.'Hallisey, Olrector r

Radiation Control Program t Massachusetts Dept. of Public Health 600 Washington Street, Room 770 Boston, MA '02111 l

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TECHNICAL SPECIFICATION CHANGE CONCERNING

". THE ROD WORTH MINIMIZER w

Prooosed Change Reference is made to Pilgrim Station Operating License No. DPR-35, page 82.

This page contains Limiting Condition-for Operation (LCO) 3.3.8.3.a. which

. concerns the Rod Worth Minimizer.r.The basis for this section is to limit peak .

enthalpy'in the event of a rod drop.

Currently, Section 3.3.B.3.a states:

No control rods shall be moved when the reactor is below 20% rated power, t'

except to shutdown the reactor, unless the Rod Worth Minimizer (RWM) is operable. A. maximum of two rods may be moved below 20% design power when the RWM is inoperable if all other rods except those which cannot be moved with control rod drive cressure are fully inserted.

The revision shall state:

The rod worth minimizer (RWM) shall b'e operable during power operation and-startup, when thermal power is less than or equal to 20% of rated thermal t

power. Entry into startup mode and withdrawal of selected control rods is

. permitted for the purpose of determining the operability of the RWM prior to withdrawal of control rods for the purpose of bringing the reactor to criticality.

Action: With the RWM inoperable, verify control rod movement and

ccmpilance with the prescribed control rod pattern by a second licensed operator or other technically qualified member of the operational staff who is present at the reactor control console. Otherwise, control rod movement may be made only by actuating the manual scram or placing the reactor mode switch in the shutdown position.

The appilcable part of the Technical Specifications Bases now states:

i

Two exceptions to the requirement for RWM operability are permitted.

Control rods may be moved to shut down the reactor, and up to two control 7 rods can be moved provided all other rods, except those which cannot be moved with control rod drive pressure, are inserted. The first exception permits the operator to shutdown the reactor in the event the RWM should become inoperable while the. reactor is critical. In this case, the operator is moving the rods to reduce the reactivity in the core. Outward

-movement of any control rod is limited to a short adjustment and the general sequence of control rod movement is always toward a safer pattern during shutdown operations. The second exception permits the control rod i drives to be moved when the~RWM is inoperative provided that all but two rods are fully inserted except for those control rods which cannot be moved with control rods drive pressure. .

The Bases will be modified by replasing this with the following:

Two exceptions to the requirement for RWM operability are permitted: (1)

The first exception permits the withdrawal.of selected control rods to allow the determination of RWM operability prior to bringing the reactor-I to' criticality. (2) The second exception permits control rod movement I

with the RHM inoperable if the movement is verified to be in compliance with the prescribed control rod patterns by a second licensed cperator, or other qualified member of the plant operational staff, who is present at the reactor control console.

Reason for Change The Pilgrim Station computer is scheduled for replacement during refueling Outage #7. The RWM could conceivably be inoperable following computer replacement, preventing plant startup because of the existing Technical Specification. We wish to remove this potential obstacle to startup by substituting the Standard Technical Specification LCO for the existing Section 3.3.3.3.a.

Safety Considerations The RWM assists and supplements the plant operator with an effective backup centrol rod monitoring routine that enforces adherence to established startup, shutdown, and low power level control rod patterns. Double checking of rod positions against established patterns by a second qualified person will adequately ensure that unacceptable patterns are not established. Therefore, the substitution of a aualified person for the RWM does not decrease safety or create an unreviewed safety question.

This proposed change has been reviewed and approved by the Operations Review Committee and reviewed by the Nuclear Safety Review and Audit Committee.

Significant Hazards Considerations The Commission has provided guidance for the application of the standards for determining whether a significant hazards consideration exists by providing examples of amendments not likely to involve significant hazards considerations (48FR14870). One such amendment, as exampled by Section (vi) of 48FR14870, involves a change which either may result in some increase to the probability or consequences of a previously analyzed accident or may reduce in some way a safety margin, but the results of the change are clearly within all acceptable criteria. The change to 3.3.8.3.a proposes to substitute the double verification of rod patterns by qualified personnel for verification of the patterns by the RHM on occasions when the RHM is inoperable. This allows an alternative method of ensuring that rod patterns prescribed by plant design and analysis are implemented. Therefore proper rod patterns will continue to be assured if this amendment is incorporated into PNPS Technical Specifications. For this reason the results of the change are clearly within all acceptable criteria, and the proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated; it does not create the possibility of a new or different kind of accident from any accident previously evaluated; and it does not involve a significant reduction in a margin of safety.

Schedule of Change This change will become effective 30 days following BECo's receipt of the Commission's approval.

Fee Determination Pursuant to 10CFR170.12(c), an application fee of $150.00 is included with this proposed amendment.