ML20155D713

Forwards Final Response to NRC 861217 Request for Addl Info Re Fire Protection Program

ML20155D713
Person / Time
Site:	Davis Besse
Issue date:	06/06/1988
From:	Shelton D TOLEDO EDISON CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
1535, TAC-60994, TAC-60995, TAC-61745, NUDOCS 8806150385
Download: ML20155D713 (11)

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TCLEDO

%mm EDISON A Cameror (nergy Canpany DONALD C. SHELTON Docket No. 50-346 [EeN2Y" License No. NPF-3 Serial No. 1535 June 6, 1988 United States Nuclear Regulatory Commission Document Control Desk Washington, D. C. 20555

Subject:

Fire Protection - Request for Additional Information (TAC Nos. 60994, 60995 and 61745)

Gentlemen:

The NRC transmitted a Request for Additional Information (RAI) regarding the Davis-Besse Fire Protection Program in letter dated December 17, 1986 (Log No. 2166). In letter dated May 23, 1988 (Serial No. 1497), Toledo Edison stated that the final response to address the remaining part of the RAI, Question 1, was undergoing final review and would'be issued by June 6, 1988. Enclosure 1 provides the final response to this question and completes Toledo Edison's response to the RAI. Please contact Mr. R. W.

Schrauder Nuclear Licensing Manager, at (419) 249-2366 if there are any questions.

Very tru yours, l

MAL:t1t Enclosure l

l cc: DB-1 Resident Inspector A. B. Davis, Regional Administrator A. W. DeAgazio, h7C/NRR D-B Project Manager D. J. Kubicki, NRC/NRR Staff Reviewer l \\

THE TOLEDO ED! SON COMPANY EDISON PLAZA 300 MAD! SON AVENUE TOLEDO, OHIO 43652 1 8806150385 880606 PDR

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Dockst No. 50-346 License No. NPF-3 Serial No. 1535 Enclosure 1 ENCLOSURE 1 Response to NRC Question 1 from RAI dated December 17, 1986

Docket No. 50-346 License No.- NPF-3 Serial No. 1535 Enclosure 1 Page 1 Response to NRC Question 1 Question 1 - Time for Operator Actions Where credit is taken for manual actions to achieve safe shutdown, provide the time limit and basis to accomplish the action before an unrecoverable plant condition occurs.

Response

In letter dated May 27, 1987 (Serial No. 1361), Toledo Edison stated that there are two post-fire shutdown procedures, i.e., AB 1203.02, "Serious Station Fire," and AB 1203.26, "Serious Control Room Fire."

These procedures identify the manual operator actions necessary to achieve safe shutdown in the event of a fire in any gi'ien fire area.

AB 1203.26 was reviewed by the NRR and Region III staffs and determined to be acceptable as documented by Inspection Report No. 83-16, dated August 30, 1984 (Log No. 1-1024) and the Safety Evaluation Report f or the Davis-Besse Fire Protection Program Corrective Action Plan dated September 23, 1983 (Log No. 1375). The NRC's approval of this procedure was based on a walkdown that verified that the minimum manpower required by rhe procedure war apable of performing the identified tesks in the necessary time frame. During the meeting on February 17-18, 1987, Mr. Dennis Kubicki, the NRC Staff Reviewer, stated that AB 1203.26 was acceptable based on the previous review conducted by the NRR and the Region III staffs.

Consequently, this response addresses the evaluation performed for AB 1203.02.

To substantiate the acceptability of AB 1203.02, Toledo Edison committed to identify the manual operator actions for a fire in areas other than the Control Room, the time to implement these actions, and the time before an unrecoverable plant condition vould occur if the associated nanual operator action (s) was not performed. The acceptance criteria and evaluation results are discussed belor.

Acceptance Criteria Based on NRC guidance provided in the February 17-18, 1987 meeting, the time for implementation of the manual operator actions is considered to be acceptable if the associated unrecoverable plant condition would not occur: 1) for at least I hour for manual operat ar actions to be completed inside the area containing the fire, or 2) for at least 30 minutes for manual operator actions to be completed outside the area containing the fire. The 1-hour criteria would also apply to manual operator actions where access and egress routes are through the area containing the fire.

Toledo Edison committed to justify the acceptability of those manual operator actions that did not satisfy this NRC guidance.

Dockat No. 50-346 License No. NPF-3 Serial No. 1535 Enclosure 1 Page 2 Time To Reach An Unrecoverable Plant Condition For the purpose of this response, an unrecoverable plant condition is defined as the loss of any shutdown function (s) for such a duration as to ultimately cause the reactor coolant collapsed liquid level to fall below the top of the active fuel height of the core and subsequent breach of the fuel cladding. Maintaining the reactor coolant level above the top of the core ensures adequate core cooling and fiosion product boundary integrity. The analysis to determine the time to reach the unrecoverable plant condition is based on the ascumption that a fire in a given fire area causes safe shutdown equipment in that fire area to assume its most detrimental position due to a credible fire-induced failure, as discussed in Toledo Edison letter dated May 27, 1987, Question 23 (Serial No. 1361). Additionally, the analysis of the time to reach an unrecoverable plant condition does not take credit for any manual operator actions, which are defined as actions taken outside the Control Room.

As discussed in the NRC neeting on October 29-30, 1987, post-fire shutdown procedure, AB 1203.02, is an interim procedure and is periodically revised to reflect the upgraded and additional fire protection features reqcired to satisfy 10CFR50, Appendix R. The response to this NRC question, therefore, reflects the planned upgrade and additional fire protection features, which will exist by restart from the sixth refueling outage.

The analysis has not taken credit for decay heat removal via the primary-side feed and bleed cooling. Only secondary-side heat removal through the steam generators is relied upon in this analysis.

The results of this evaluation show that an unrecoverable plant condition could occur due to the fire-induced loss of any one of the following shutdown functions referred to in 10CFR50, Appendix R, Section III.L.2, without the timely completion of the associated manual operator actions:

1. Decay heat removal f rom the core (e.g. , loss of the ability to supply auxiliary feedvater to the steam generators.)

2. Supporting functions necessary for the operation of the safe shutdown equipment required in the crent of a fire (e.g.,

Service Water System, Component Cooling Wster System)

3. Reactor coolant make-up capabili6y (e.g., loss of the ability to add borated water to the reactor coolant system via the makeup and high pressure injection pumps)

The results of the analysis demonstrate tt~.at the core remains suberitical for at least 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> due to control rod insertion. No credible fire-induced failure would create an overcooling event so severe r - to cause a return to criticality. Plant conditions beyond 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> were not evaluated since 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is sufficient time to perform any manual operator actions specified by AB 1203.02. Tassible loss of suberiticality by credible fire-induced failures other than an overcooling event will be determined and appropriate corrective actions taken prior to restart from the sixth refueling outage.

Dockat No. 50-346 License No. NPF-3 Serial No. 1535 Enclosure 1 Page 3 It should be noted that certain manual operator actions specified by AB 1203.02 are necessary to establish the aforementioned shutdown functions. Pending the completion of the associated manual operator actions, one or more of the performance goals specified by 10CFR50, Appendix R, Section III.L.2 may not be maintained at all times and the 1._ cor coolant process variables may temporarily exceed that predicted for a loss of normal A. C. power specified by 10CFR50, Appendix R, SectionIII.L.1. The degraded shutdown functions would be restored so as to return the reactor coolant process variables to those predicted for a loss of normal A. C. power and to return the plant to within the Appendix R performance goals. However, the reactor coolant inventory may not be restored to within the pressurizer level indications for an extended time.

Nonetheless, the fission product boundary would not be affected and an unrecoverable plant condition as defined above would not occur. As discussed with NRC Staff members on April 27 and May 3, 1968, thi- is considered to satisfy the intent of 10CFR50, Appendix R.

Time to Perform Manual Operator Actions There are a total of 374 manual operator actions for 26 fire areas identi-fied in AB 1203.02. In the event of a fire, only those actions specified for the respective fire area containing the fire are to be performed.

The estimated time to perform each manual operator action is based on a walkdown of certain actions specified by AB 1203.02. The time to perform those manual operator actions that were not part of the walkdown were conse rva ' ely estimated based on similar or more complex actions whose times have been measured. The time to perform a manual operator action is based on the time to reach and locate the specified equipment and the time to place that equipment in operation. The walkdown did not actually operate equipment such as opening valven or tripping breakers. Consequently, the timea to perform the manual _ operatcr actions are based on the times to l

reach and locate the equipment and the following assumed durations:

l 3 minutes to manually operate valves, and 10 minutes to establish temporary l ventilation; no additional time was included for tripping a breaker.

1 Evaluation Results Nineteen (19) manual operator actions that currently do not satisfy i the aforementioned NRC guidance and whose resolution is not currently identified by the Davis-Besse Appendix R Compliance Assessment Report have been identified. Attachment 1 identifies these 19 actions by fire area, the applicable acceptance criteria, the proposed resolution and whether the propo=ed resolution following implementation has been confirmed to satisfy the ac aptance criterie.

Of these 19 actions, 6 will be resolved by modifications such that manual cperator actions outside the Control Room would not be required.

One modificacion involves adding solenoid-operated flow co, trol valves to the auxiliary feedwater system that can le aperated from the Control 1

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Lockat No. 50-346 License:No. NPF-3' Seria) No-1535' Enclosure-1 Page 4' P.oom in .the event of a fire. - These components will be installed prior to restart from the"current fifth refueling'autage, f The other modifications involve rerouting or fire wrapping certain circuits which are scheduled to be completed prior'to restart from'the sixth refueling outage.

An additional 8 manual operator actions will be resolved by the

, installation of cavitating venturis in the auxiliary feedwater system.

These cavitating venturis will extend the time to' reach an unrecoverable plant condition associated with these 8 actions such that the time satisfies the acceptance criteria provided by the NRC. These cavitating venturis will be installed prior to restart from ine current fifth refueling outage.

The remaining 5 actionn will be resolved by studies and possible testing. These studies or possible testing will address a fire-induced loss of tto Service Water System and the ventilation systems required for the Component Cooling Water System and Service Water Pump Rooms. This effort will establish better data on the limiting times for these spstems to be placed into operation in the event of a fire and will determine that the time to reach an unrecoverable plant condition for these 5 actions satisfies the aforementioned NRC guidance, or will identify appropriate corrective actions. These studies and any idencified corrective actions will be completed: prior to restart from the sixth refueling outage.

Additionally, AB 1203.02 will be revised prior to restart from the fif th refueling outage to specify the operation of the motor-driven feedwater pump in certain fire areas. This will eliminate certain manual operator actions specified by AB 1203.02, thereby simp 1fying AB.1203.02 and enhancing the overall. capability to respond to a fire.

From this review, Toledo Edison also determined that the single generator provided to power the temporary ventilation specified by AB1203.02.is not sufficient and is too difficult to maneuver. Two new gasoline-engine powered electric generators, mounted on two-wheel dollies to facilitate their movement, have been purchased. Prior to restart from the current fif th refueling outage, the generators will be placed in the plant, and the implementation of necessary procedures and operator training to use the generators will be completed.

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4 Dockst No.- 50-346 License No. NPF-3 Serial No. 1535 Attachment 1 ATTACFMENT 1 MANUAL OPERATOR ACTIONS REQUIRING RESOLUTION I

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AB 1203.02 MANUAL OPERATOR ACTIONS REQ 1' IRING RESOLUTION -

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SATISFIES REQUIRED- APPLICABLE PROPOSED ACCEPTANCE MANUAL SHUTDOWN ACCEPTANCE METHOD OF -CRITERIA FIRE AREA ACTION FUNCTION CRITERIA" RESOLUTION Pcst-6th RF0 q Fire Area A Depower and Reactor 30 Mins AFW Cavitating Yes manually posi- Heat .

Venturi tion MS-106 Removal a

4 Fire Area BF Depower and Supporting 30 Mins- SW Study. Pending manually close Function study.

SW-1399 Fire Area BF Start the Supporting 30 Mins SW Study Pending Backup SW Pump Function study

Fire Area D Depower and Reactor 30 Mins AFW Cavicating Yes open manually Heat Venturi position MS-106 Removal Fire Area DB Depower and Reactor 30 Mins AFW Cavitating Yes open AF-3870 Heat Venturi Removal i

Fire Area DF Depower and Reactor 30 Mins AFV Ccvitating Yes ma aally posi- Heat Venturi tion valve -Removal MS-106 i

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AB 1203.02 MANUAL OP5RATOR ACTIONS REQUIRING RESOLUTION SATISFIES.

REQUIRED APPLICABLE  : PROPOSED ACCEPTANCE' HANUAL. SHUTDOWN ACCEPTANCE- METHOD OF . CRITERIA. __

M FIRE AREA ACTION FUNCTION CRITERIA RESOLUTION Post-6th RF0 i

- ' Fire Area DJ Depower and Reactor 30 Mins AFW Cavitating Yes manually posi- Heat Venturi tion valve Removal MS-106

, Fire Area EE Depower and Reactor- 30 Mins AFW Cavitating Yes-manually open Heat - Venturi AF-608 Removal Depower and 30 Mins AFW Cavitating Fire Area'F Reactor Yes l manually open Heat Venturi

' AF-3870 Removal l Fire. Area G Depower and Reactor 30 Mins Flow control Yes 2

manually posi- Heat- valve -

tion MS-107 -Removal-i 4

Fire Area II Depower and Supporting 1 Hour SW. study Pending manually close Function . study SW-1399. In the event fire is

! located in Room 53 such that-access to valve is j_ not possible, manually.

! close valves SW-630, j 631 and 632 in

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Room 334

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AB 1203.02 MANUAL OPERATOR ACTIONS REQUIRING RESOLUTION SATISFIES REQUIRED APPLICABLE PROPOSED ACCEPTANCE MANUAL SHUTDOWN ACCEPTANCE METHOD OF CRIIERIA FIRE AREA ACTION FUNCTION CRITERIA RESOLUTION- Post-6th RF0 Fire Area Q Depower and Reactor 30 Mins AFW Cavitating Yes open AF-3870 Heat Venturi Removal Fire Area Q Eepower and open Support 30 Mins Circuit heroute- Yes damper HV-5597 Function Fire Area R Disconnect wire Reactor 30 Mins Flow control Ye for governor Heat valve control valve Removal and regulate flow using local speed knob Fire Area R Start. Backup Supporting 30 Mins SW study Pending SW Pump Function study Fire Area R Depower and Supporting 30 Mins Circuit fire Yes open damper Function wrap HV-5305A.

Fire Area T Start the unaf- Supporting 30 Mins Circuit fire Yes fected CCW Pump Function wrap at the breaker and place that train equipment in service.

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ATTACHMENT 1 -

AB 1203.02 MANUAL OPERATOR ACTIONS REQUIRING RESOLUTION SATISFIES REQUIRED APPLICABLE PROPOSED ' ACCEPTANCE MANUAL SHUTDOWN. ACCEPTANCE METHOD OF CRITERIA-FIRE AREA ACTION MJNCTION . CRITERIA RESOLUTION Post-6th RFO-Fire Area T Establish tem- Supporting 30 Mins CCW study Pending porary ventila- Function study tion in the CCW Pump Room Fire Area U Establish tem- Supporting 30 Mins Circuit fire Yes porary ventila- Function wrap tion in the CCW Pump Room i

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