ML13330A271

Provides Status of Investigation of Anchorage of safety- Related Electrical Equipment,In Response to NRC 800101 & 0728 Requests.Mods Associated W/Items Identified in Encl 1 Scheduled for Completion by 810501

ML13330A271
Person / Time
Site:	San Onofre
Issue date:	03/25/1981
From:	Baskin K Southern California Edison Co
To:	Crutchfield D Office of Nuclear Reactor Regulation
References
NUDOCS 8103310495
Download: ML13330A271 (8)

Text

Southern California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD, CALIFORNIA 91770 K. P. BASKIN March 25, 1981 TELEPHONE MANAGER OF NUCLEAR ENGINEERING, (213) 572.1401 SAFETY, AND LICENSING Director of Nuclear Reactor Regulation Attention: D. M. Crutchfield, Chief Operating Reactors Branch No. 5 19 81 1','

Division of Licensing U.S.

CLAR EGULToRy U. S. Nuclear Regulatory Commission Washington, D.C.

20555 Gentlemen:

Subject:

Anchorage and Support of Safety Related Electrical Equipment San Onofre Nuclear Generating Station Unit 1 By letters dated January 1 and July 28, 1980, you requested an investigation of the anchorage of safety-related electrical equipment. Our program and the results of our initial investigations were provided to you by letters dated March 18 and May 23, 1980.

The purpose of this letter is to provide you a status of the program.

Following the identification of anchorages provided in our May 23 letter, preliminary assessments were made for all of the electrical equipment. Based on the results of these preliminary assessments, interim modifications were implemented during July and August of 1980. These modifications are identified in Enclosure 1.

Following completion of the interim modifications, detailed analyses were initiated on the anchorages of all of the electrical equipment. These analyses were divided into two phases.

The first phase included all equipment at grade elevation for which response spectra were available (the 2/3 g Housner free-field ground response spectrum). The results of these analyses generally confirmed the adequacy of the preliminary assessments and the interim modifications with five exceptions. The five items are the battery racks, the UPS battery rack, the HV control board, the 5kVa inverter and the battery chargers. Modifications associated with these five items are identified in Enclosure 1 and are scheduled for completion prior to May 1, 1981.

The second phase of the program includes all equipment located in the control room. The analysis of the anchorage of safety related electrical equipment in the control room is currently in progress. Since in-structure response spectra are not yet available for the control room, we have decided to proceed with the analyses using estimated spectra.

The analyses are scheduled for completion by March 31, 1981.

Results of these analyses along O/

with a schedule for implementation of any required modifications will be submitted by April 13, 1981.

D.

March 25, 1981 Your letters of January 1 and July 28, 1980 also requested an evaluation of the potential for non-seismic Category I auxiliary items to become dislodged by an earthquake and damage safety-related electrical equipment. As described in our March 18, 1980 letter, in response to this request we have conducted several walk-throughs of the plant in order to identify non-Seismic Category I equipment which could potentially dislodge, impact and damage safety-related electrical equipment. As a result of these walk-throughs, a punch list of items which require further evaluation or disposition was generated. This list is provided as Enclosure 2. The results of the evaluation of these items as well as a schedule for any required modifications will be provided by April 13, 1981.

If you have any questions on this matter, please contact me.

Sincerely, Enclosures Page 1 of 5 Results of Evaluation of Anchorage of Safety Related Electrical Equipment San Onofre Nuclear Generating Station, Unit 1 Was Anchorage Item Equipment Type of Modified Since Jan. 1, No.

Description Location Anchorage 1980; If So, How Reference

1.

4160 V Switchgear 4 kV Switchgear Plug welded to Yes; Added plug Calc. No. S-A-01 pp. 1-10, Bus 1C & 2C Room embedded channels welds to embedded channels

2.

480 V Switchgear 4 kV Switchgear Welded to embedded Yes; Added plates Calc. No. S-A-01 pp. 11-15

1. 1 Room channels and welded to embedded channels

3.

480 V Switchgear 4 kV Switchgear Welded to embedded No Calc. No. S-A-01 p. 16

1. 1B Room channel

4.

Motor Control 4 kV Switchgear Welded to embedded Yes; Added plates, Calc. No. S-A-01 p. 17 Center #1 & #1A Room channel welded to sub-base and embedded channels

5.

Auxiliary Relay 4 kV Switchgear Bolted to wall No Calc. No. S-A-01 pp. 18-2b Panels Room by unistrut

6.

Reactor Trip 4 kV Switchgear Welded to embedded Yes; Added welds to Calc. No. S-A-01 pp. 26-32 Switchgear Room channels embedded channel

7.

120 VAC Power 4 kV Switchgear Welded to embedded Yes; Weld plates Calc. No. S-A-01 pp. 33-39 Distribution Room channel between sub-base and Panel embedded channel

8.

H/V Control 4 kV Switchgear Welded to embedded Yes; Weld plates Calc. No. S-A-01 pp. 40-52 Board Room angle between base and embedded channel.

Also, additional plates will be welded between base and embedded channel.

Page 2 of 5 Was Anchorage Item Equipment Type of Modified Since Jan. 1, No.

Description Location Anchorage 1980; If So, How Reference

9.

480 V Switchgear 480 V Switchgear Welded to embedded Yes; Added plates Calc. No. S-A-02 pp. 1-12

1. 2 & #3 Room channel and welded to embedded channels

10.

480 V Switchgear 480 V Switchgear Bolted down by No Calc. No. S-A-02 pp. 13-24

1. 2B Room means of anchor bolts

11.

DC Contactors 480 V Switchgear Bolted to wall by No Calc. No. S-A-02 pp. 24-32 (D12 & 013)

Room concrete fastener and unistrut

12.

Motor Control 480 V Switchgear Welded to embedded Yes; Added plates, Calc. No. S-A-02 pp. 33-36 Center #2 Room channel welded to sub-base and embedded channel

13.

Main Control Control Room Welded to existing Yes, Added plug Dwg. 5170701-A Board Console embeds welds Calc. No. S-B-01 (C03 & C06)

14.

Process Control Control Room Bolted to adjacent No Dwg. 5170701-A Racks R6 & R7 cabinets

15.

Process control Control Room Bolted to floor Yes; Welded angles Dwg. 5170701-A Racks R10, R11, to sub-base and R1 through R5 bolted them to floor

16.

Process Control Control Room Bolted to floor Yes; Welded angles Dwg. 5170701-A and Racks R12, R13 to sub-base and Dwg. 5170702-A

& R14 bolted them to floor Calc. No. S-B-01

17.

Vertical Control Control Room Bolted to floor Yes; Welded angles Calc No. -S-B-01 Boards (C05, C09 and ceiling to sub-base and C12 & C13) bolted them to floor

18.

Nuclear Instrum.

Control Room Bolted to floor Yes; Welded angles Dwg. 5170701-A System (C10) to sub-base and Calc. No. S-B-01 bolted them to floor

Page 3 of 5 Was Anchorage Item Equipment Type of Modified Since Jan. 1, No.

Description Location Anchorage 1980; If So, How Reference

19.

Radiation Moni-Control Room Bolted to floor Yes; Welded angles Dwg. 5170701-A toring System to sub-base and Calc No. S-B-01 bolted them to floor

20.

CSAS Inverter Control Room Bolted to floor No Calc. No. S-B-01 and wall

21.

Diesel Generator Control Room Bolted to floor No Dwg. 5170701-A Control Boards Calc No. S-B-01 SPG1 (C41) &

SPG2 (C42)

22.

SEP Relay Panels Control Room Bolted to floor No Dwg. 5170701-A A & B and wall Calc. No. S-B-01 (C60 & C61)

23.

Vital Bus Control Room Bolted to floor Yes; Added concrete Calc. No. S-B-01 Assembly (C16) fastener

24.

Safeguard Load Control Room Bolted to floor No Dwg. 5170701-A Sequencing System Calc. No. S-B-01

25.

Inverter #4 Control Room Bolted to floor No Dwg. 5170701-A Calc. No. S-B-01

26.

Station Battery Battery Room Concrete Fasteners No; However, racks Calc. No. S-A-03 pp. 1-48

& Battery Racks will be redesigned and constructed (D04 & DO4R)

27.

125 VDC Switch-D.C. Switch-Bolted to floor No Calc. No. S-A-04 pp. 1-9 board No. 1 (001) gear Room

28.

Battery Chargers D.C. Switch-Bolted to floor No; However, channel Calc. No. S-A-04 pp. 10-18 A & B (D02 & D03) gear Room bases will be welded to sub-base

Page 4 of 5 Was Anchorage Item Equipment Type of Modified Since Jan. 1, No.

Description Location Anchorage 1980; If So, How Reference

29.

Inverters Nos.

D.C. Switch-Partial anchorage-Yes; Added plates Calc. No. S-A-04 pp. 19-25 1, 2 & 3 gear Room bolts with nuts and welded to and vendor seismic report missing embedded angle; Also additional welds will be made

30.

1250 kVA Station Outdoor Bolted Yes; Added weld Calc. No. S-A-05 pp. 1-8 Service Trans-between skid beams formers #1, & #2 and friction plates

31.

Auxiliary Control Turbine Area Bolted to floor No Calc. No. S-A-06 pp. 1-11 Panel (C38)

32.

Uninterruptible Turbine Area Bolted to floor No Calc.

No. S-A-06 pp. 12-20 Power Supply (Battery Charger

& Inverter)

33.

Battery & Battery Turbine Area Bolted to floor No; However addi-Calc. No. S-A-06 pp. 21-60 Rack for UPS tional concrete fasteners and bracing will be added

34.

MCC #3 Turbine Area Welded to embedded Yes; Added plates Calc. No. S-A-06 p. 61 channel to act as backup bars to permit welding

35.

Diesel Engines Diesel Genera-Bolted to floor No Calc. No. S-A-07 p. 1 tor Building

36.

Diesel Generators Diesel Genera-Bolted to floor No Calc. No. S-A-07 p. 2 tor Building

37.

Motor Control Diesel Genera-Bolted to floor No.

Calc. No. S-A-07 pp. 3-7 Centers lB & 2B tor Building

Page 5 of 5 Was Anchorage Item Equipment Type of Modified Since Jan. 1, No.

Description Location Anchorage 1980; If So, How Reference

38.

Battery Chargers Diesel Genera-Bolted to floor No Calc. No. S-A-07 pp. 8-13 C & D tor Building

39.

High Voltage Diesel Genera-Bolted to floor No Calc. No. S-A-07 pp. 14-19 Exciter Cabinets tor Building (D06 & D07)

40.

Low Voltage Diesel Genera-Bolted to floor No Calc. No. S-A-07 pp. 20-25 Exciter Cabinets tor Building (E08 & E09)

41.

DC Distribution Diesel Genera-Welded to embedded No Calc. No. S-A-07 pp. 26-32 Switchboard tor Building channel

42.

Terminal Boxes Diesel Genera-Bolted to floor No Calc. No. S-A-07 pp. 33-36 for D.G. No. 1 tor Building

& No. 2 (GG16 & FG17)

43.

D.G. No. 1 &

Diesel Genera-Bolted to floor No Calc. No. S-A-07 pp. 37-41 No. 2 Engine tor Building Control Panels (GC40 & FC48)

44.

D.G. No. 1 &

Diesel Genera-Bolted to floor No Calc. No. S-A-07 pp. 42-46 No. 2 Local tor Building Control Panels (FC44 & GC45)

45.

Battery Rack Diesel Genera-Bolted to floor No Calc. No. S-A-07 pp. 47-69 No. 2 tor Building O

46.

CSAS Logic Control Room Bolted to floor Yes; Welded angles Dwg. 5170701-A and Train A and welded to sub-base and Dwg. 5170702-A (FC62 & GC62) bolted them to floor. Calc. No. S-B-01 Also added weld sub-base to cabinets

47.

MCC 2A Reactor Auxiliary Welded to floor Yes; Welded base to Calc. No. S-B-02 Building embedded steel Non-Seismic Category I Auxiliary Equipment 4 kV Room

1. Fire extinguisher, wheeled type

2. Non-safety related cabinets

3. Table 480 Volt Room

1. Fire extinguisher, wheeled type

2. Non-safety related cabinets

3. Spare circuit breakers Turbine Building

1.

Gas bottles

2. Monitoring equipment cabinet

3.

Excitation switchgear and power system stabilizer cabinets Control Room

1. Ducting

2. Hanging lights

3. Bookcases and tables

4.

Non-safety related cabinets North Diesel Generator Building

1.

Work bench

2.

Table

3.

Eye wash bottle

4. Miscellaneous unattached ladders South Diesel Generator Building

1. Miscellaneous unattached ladders

2. Work bench Reactor Auxiliary Building

1. Construction items D.C. Switchgear and Battery Rooms

1. Communications battery rack