ML20245F566
| ML20245F566 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, 05000000 |
| Issue date: | 08/01/1989 |
| From: | Kovach T COMMONWEALTH EDISON CO. |
| To: | Davis A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| NUDOCS 8908140413 | |
| Download: ML20245F566 (3) | |
Text
{{#Wiki_filter:6, Crmm:nwnith Edison d A }1 M.<: 72 West Adams Street. Chicago, Illinois x ge$. sL JAddress Reply to: Post Off6Bdi767~ q V j ? # Chicago, Illinois 60690 0767 j 1 ~ August.1,-1989 ~Mr. A. Bert Davis-Regional Administrator-U.S. N.uclear Regulatory Commission j Region III' l '799 Roosevelt Road Glen Ellyn, IL-60137 Subjects. Byron Station Units 1 and 2 l Response to NRC ESF Surveillance Testing at j Remote Shutdown Panel i NRC Inspection Report Nos. 50-454/89014 and 450-455/89016-01 i NRC Docket Nos. 50-454 and 50-455 c4
Reference:
July 11,. 1989 letter from W.D. Shafer j to Cordell Reed
- l
DearMr. Davis:
j In the referenced Inspection Report, an open item was ident1'fied ) 'concerning ESF circuits associated with the Remote Shutdown Panel (RSP) at j Byron Station that are not subject to ongoing surveillance testing. -The circuits involved provide automatic start signals to the Auxiliary reedwater (AF), Centrifugal Charging (CV), Component Cooling (CC), and Essential Service ] Water (SK) pumps in the event of a Safety Injection (SI) or Loss of Offsite j Power.(LOOP)'while the equipment is being controlled from the-RSP. The .l attached evaluation from the Commonwealth Edison Nuclear Engineering j Department supports the Station's past testing practice. Commonwealth Edison reviewed the feasibility of removing the SI/ LOOP l circuits from the RSP and determined that removal of the circuits was not economically justified at this. time. Although the-circuits are not regaired . j per the UFSAR, the circuits will remain installed, and both Byron and j Braidwood Station will perform periodic testing to verify their operability. Byron and Braidwood will incorporate testing of these circuits into the l Station surveillance program. 1(2) BOS 3.2.1.1.a-1 (2), " Unit One (Two) Train j A (B] Manual Safety Injection and Manual Phase A Initiation Surveillance", and 1(2) BOS 3.2.1-941, "ESFAS Instrumentation Slave Relay Surveillance (Train A -{ Autillary Feedwater Actuation, Relay K633)", will be revised to test the l autometic start signals. The surveillance will be performed on an 18 month. j and quarterly basis respectively. . l i Commonwealth Edison is continuing to evaluate the future removal of l the auto-start contsets. Please direct any questions regarding this matter to this office. L l Very truly yours, l 8908140413 890801 i M PDR ADOCK 05000454 $ T.J. ,ovach G PNU 1% Nuclear Licensing Maneger yg i {L /sc1:0235T:1 cc: Resident Inspector-Byron Resident Inspector-Braidwood Office of Nuclear Facility Safety-IDNS l AUG 's 1989 1
N-r ~ ATTACHMENT' .v.. . RESPONSE TO NRC CONCERN-ESF SURVEILLANCE TESTING AT THE REMOTE SHUTDOWN PANEL (BYRON /BRAIDH000) NRC CONCERN -NRC has raised a concern that certain ESF circuits associated with the Remote Shutdown. Panel (RSP) at Byron and Braidwood are not subject to ongoing surveillance testing. The circuits involved provide-automatic start signals. to the Auxiliary Feedwater (AF), Centrifugal Charging (CV). Component Cooling (CC), and Essential Service Water (SX) pumps'in the event of an SI or LOOP while the equipment is being controlled from the RSP. Each train of the above equipment has a local / remote transfer switch which includes a set of contacts' that, when made up, allow SI/ LOOP auto start of the equipment. SI/ LOOP auto start of these pumps via this circuit is not currently tested on an ongoing-basis.- These have been successfully tested once per Safety Evaluation Report [Ref. 9,10,11] requirements.
RESPONSE
The purpose of the RSP is to provide a remote location for safe shutdown and hot standby / hot shutdown maintenance of the plant if the control room has to be: evacuated. The design basis-for control room evacuation'does not consider a concurrent ANS condition II III, or IV event, nor.a single failure [Ref.1).. The safe shutdown analysis presented in the Byron /Braidwood Fire Protection Report [Ref. 23 describes the Station's ability to safely shutdown the plant in the event of a fire. Procedures 1/2 BOA /Bw0A-PRI-5 [Ref. 3,4,5,6] are in place to dictate the actions necessary to achieve and maintain safe shutdown of the unit if the control room becomes inaccessible. 1 In accordance with regulatory guidance [Ref.'7.8], the fire hazards safe' I . shutdown analysis assumes that the postulated fire does not occur j simultaneously with other accidents, events, or phenomena (such as design-basis accidents), with the exception of a LOOP. The analysis. describes the Station's ability to cope with a control room evacuation with and without offsite power available. Credit is taken for manual control of equipment required for safe shutdown from the RSP and other remote locations and no l . automatic actuation is assumed. i Further, based on current regulatory guidance, there is no-requirement to i postulate accident conditions which require auto start capability of ECCS pumps for mitigation concurrent with control room evacuation. Therefore, the SI-auto start circuits associated with the RSP are not required. _ Since the auto start circuits are considered to be beyond the design intent of the RSP,. they could be deleted via a modification. However, there is no~ adverse effect to leaving the circuits in place. If left in place, the contacts associated with these auto starts could fail'without affecting operability of the RSP manual. controls. Engineering has determined that if the Station chooses to leave the contacts in place, ongoing surveillance testing of the contacts is not required. L J
e REFERENCES i
- 1) Byron /Braidwood UFSAR, Section 7.4.1.3
- 2) Byron /Braidwood Fire Protection Report, Section 2.4
- 3) Byron Procedure 1 BOA-PRI-5, " Control Room Inaccessibility - Unit 1"
- 4) Byron Procedure 2 BOA-PRI-5, " Control Room Inaccessibility - Unit 2"
- 5) Braidwood Procedure 1 BOA-PRI-5, " Control Room Inaccessibility --
Unit 1" 6)~ Braidwood Procedure 2 BOA-PRI-5, " Control Room Inaccessibiitty - Unit 2"
- 7).USNRC Standard Review Plan, NUREG-0800. Sections 7.4 & 9.5.1
- 8) USNRC Branch Technical' Position CMEB 9.5-1
- 9) Byron Safety Evaluation Report, NUREG - 0876 February, 1982
- 10) Byron Safety Evaluation Report, NUREG-0876 Supplement No. 7 November, 1986
- 11) Braidwood Safety Evaluation Report, NUREG-1002, November, 1983.
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