NUREG-0612, Safety Evaluation Supporting Util Request to Delete Three Commitments in Response to NUREG-0612 Re Heavy Load Control on 5-ton Electric Monorail Hoist W/Integral Trolley & 4-ton Monorail Chain Hoist W/Geared Trolley

Safety Evaluation Supporting Util Request to Delete Three Commitments in Response to NUREG-0612 Re Heavy Load Control on 5-ton Electric Monorail Hoist W/Integral Trolley & 4-ton Monorail Chain Hoist W/Geared Trolley

ML20247N229
Person / Time
Site:	Sequoyah
Issue date:	05/26/1989
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20247N226	List: NUREG-0612, Safety Evaluation Supporting Util Request to Delete Three Commitments in Response to NUREG-0612 Re Heavy Load Control on 5-ton Electric Monorail Hoist W/Integral Trolley & 4-ton Monorail Chain Hoist W/Geared Trolley
References
RTR-NUREG-0612, RTR-NUREG-612 NUDOCS 8906050273
Download: ML20247N229 (3)

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/ 'o g UNITED STATES NUCLEAR REGULATORY COMMISSION 5 p WASHINGTON, D. C. 20655 e \"..../ .

ENCLOSURE-SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION  !

I REVISION TO THE HEAVY LOAD CONTROL COMMITMENTS SEQUOYAH UNITS 1 AND 2 TENNESSEE VALLEY AUTHORITY DOCKET N05. 50-327/328

1.0 INTRODUCTION

In NUREG-0612. " Control of Heavy Loads at Nuclear Power Plants," dated July 1980, the staff provided guidelines for the control of heavy loads. Based on the staff's review of the licensee's commitments provided in its submittals, the staff issued its safety evaluation for Sequoyah (SQN), Units 1 and 2, in a letter from T. Novak (NRC) to H. G. Parris (TVA) dated March 26, 1985. Therein, the staff concluded that the guidelines of NUREG-0612 had been satisfied at SQN.

Upon performing' additional euluations in'to the comitments that were originally made in SQN's NUREG-0612 submittals (Reference 4.1), TVA determined that three of the comitments should be deleted. They are heavy load control on 5-ton electric monorail hoist with integral trolley, 4-ton monorail chain hoist with geared trolley, und 3-ton jib crane with 3-ton wire rope electric hoist and chain-driven trolley. The staff's evaluations of these three changes to the heavy load commitments are discussed below.

2.0 EVALUATION  ;

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'2.1 Item 4 (Reference 4.1) "5-Ton Electric Monorail Hof st With Integral Trolley" Commitment , ,k TVA originally comitted to initiate a design change request (DCR) to locate trolley stops on the 5-ton monorail above the evaporator feed filter to provide e a safe load path. '

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Revised Response The load handled by this hoist is the concrete plug for the waste evaporator feed filter. This plug is 29 inches square, and the concern was that it could poten-

• ially be lifted near the residual heat removal (RHR) room cooler supply control valve and the RHR pump A-A minimum flow valve switch. -

Licensee's examination of the calculations for the plug shows that the weight of the plug is 1,789 pounds. The heavy load is defined as any load, carried in a given area after a plant becomes operational, that weighs more than the combined weight of a single spent fuel assembly and its associated handling tool for the

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. 2- l specific plant in question. According to Technical Specification Change 87-41, 2,100 pounds is the minimum weight for a heavy load. This lift is, therefore, not a heavy load.

In addition to the above, a field inspection was performed and field measurements were taken of the monorail, the valve, and the minimum flow valve switch. It was determined through field inspection and measurements that there is enough clearance between the valve and plug and between the minimum flow valve switch and the plug.

Because of this clearance and because SQN only uses slings that meet the requirements of American National Standards Institute B30.9, lifting this concrete plug in the vicinity of the valve and minimum flow valve switch is acceptable; and there is no need for a trolley stop on this monorail.

Therefore, the staff agrees that the work associated with this commitment is not required.

2.2 Item 5 (Reference 4.1) "4-Ton Monorail Chain Hoist With Geared Trolley" Comitment TVA originally comitted to initiate a DCR to add trolley stops to the monorail, located in the auxiliary building on elevat'on 690 ft., to provide a safe load path.

Revised Response TVA provided the following information on this commitment for a safe load path, The work associated with this comitment pertains to the monorail over component cooling pumps IB-B and 28-B. The original comitment was based on the possibility that pump 1B-8 could be lifted over pump 28-B (or vice versa);

and, if the lifted pump was dropped, loss of component cooling system (CCS) inventory could occur. This scenario in turn could adversely affect the unit's ability to achieve and maintain a safe shutdown condition. A trolley stop was to be provided to ensure that one pump was not lifted over another.

Adding a trolley stop would prohibit lifting CCS pumps 18-B or 28-B over each other but would not keep the CCS pump motor from being lifted over the pump, causing the same concern. Installing a trolley stop would also interfere with setting down the pump or motor in the setdown area.

The addition of a trolley stop is not required because damaging CCS pumps 1B-B or28-B(and/orassociatedpiping)wouldonlycausealossofA-traininventory (these pumps are run in the A-train piping). Loss of A-train inventory because of either a dropped CCS pump or motor would not affect the B train of the CCS because the B-train inventory is separated from the A-train inventory, and shutdown could be achieved using the B train. This loss is bounded by the worst-case single failure.

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p; s Worst-case flooding as a result of dropping a pump or pump motor is a total' loss of the A-train inventory that is bounded by the flood postulated in the moderate energy line break study.

.Therefore, TVA has concluded and the staff agrees that the work associated with this comitment is not required.

2.3 Item 6 (Reference 4.1? "3-Ton Capacity Jib Crane With 3-Ton Capacity-Wire Rope Electric Hod St and Chain Driven Trolley" Connitment TVA originally committed to revise Sequoyah Standard Practice SQM56 (curreritly Maintenance Instruction [MI] 6.22) to include the 3-ton jib crane in the reactor building on the list of heavy load handling equipment for miscellaneous lifts greater than 2,000 pounds.

Revised Response.

Based upon a review of TVA drawings (i.e., equipment drawings, mechanical

. instrumentation and control drawings, and mechanical piping drawings), TVA determined that the 3-ton-capacity jib crane does not need to be added to MI-6.22.

As a result of TVA's review, sample lines and control air lines were determined to be the only potential targets for a heavy load droy by this crane. However, TVA determined that there is sufficient physical separation from the load path to preclude this occurrence.

Therefore, TVA has concluded.and the staff agrees that the work associated with this comitment is not required.

3.0 CONCLUSION

For the. reasons stated above, the licensee's request for the withdrawal of their commitments is found to be' reasonable and acceptable.

4.0 REFERENCE

1. L.M. Mills's (TVA) letter to E. Adensam (NRC) dated March 1, 1982.

Principal Contibutor: S. B. Kim Dated:

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