ML17286A912

LER 90-023-01:on 901004,pressure Loss Occurred in Containment Instrument Air Sys When Relief Valve CIA-RV-2 Opened Prematurely.Caused by Inadequate Mgt Programs & Work Practices.Sys Requirements reviewed.W/910701 Ltr

ML17286A912
Person / Time
Site:	Columbia
Issue date:	11/05/1990
From:	John Baker, Fies C WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GO2-91-126, LER-90-023, LER-90-23, NUDOCS 9107110207
Download: ML17286A912 (10)

Text

ACCELERATED DISTRIBUTION DEMONSTPWTION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9107110207 DOC.DATE: 90/11/05 NOTARIZED: NO DOCKET FACIL:50-397 WPPSS Nuclear Project, Unit 2, Washington Public Powe 05000397 AUTH. NAME AUTHOR AFFILIATION FIES,C.L. Washington Public Power Supply System BAKER,Z.W. Washington Public Power Supply System RECIP.NAME RECIPIENT AFFILIATION R SUBZECT: LER 90-023-01:on 901004,pressure loss occurred in containment instrument axr sys when relief valve CIA-RV-2 opened prematurely. Caused by inadequate mgt programs & work practices.Sys requirements reviewed.W/910701 ltr.

DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR ENCL SIZE:

TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.

NOTES RECIPIENT COPIES RECIPIENT COPIES D ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 D ENG,P.L. 1 1 INTERNAL: ACNW 2 2 ACRS 2 2 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1

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NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOiil P 1-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROiiI DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!

FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED: LTTR 33 ENCL 33

WASHINGTON PUBLIC POWER SUPPLY SYSTEM P.O. Box 968 ~ 3000 George Washington Way ~ Richland, Washington 99352 Docket No. 50-397 July 1, 1991 G02-91-126 Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Subject:

NUCLEAR PLANT NO. 2 LICENSEE EVENT REPORT NO. 90-023-1

Dear Sir:

Transmitted herewith is Licensee Event Report No. 90-023-1 for the WNP-2 Plant. This report is submitted in response to the report requirements of 10CFR50.73 and discusses the items of reportability, corrective action taken, and action taken to preclude recurrence.

Very truly yours, J. W. Baker (H/D 927M)

WNP-2 Plant Manager JWB:lr

Enclosure:

Licensee Event Report No. 90-023-l cc: Hr. John B, Martin, NRC Region V Hr. C. Sorensen, NRC Resideni. Inspector (H/D 90lA)

INPO Records Center Atlanta, GA Hr. D. L. Williams, BPA (H/D 399)

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NRC FOAM 366 (6S9)

LICENSEE EVENT REPORT {LER)

U.S. NUCLEAR REGULATORY COMMISSION t APPROVED OMB NO. 31504(04 EXPIRES: 4/30/92 ESTIMATED BURDEN PER RESPONSE TO COMPLY WTH THIS INFORMATION O)LLECTION RFQUESTI 608) HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS AND REPOATS MANAGEMENT BRANCH IPS30), US. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20566, AND TO THE PAPERWORK REDUCTION PROJECT (31600(04), OFFICE OF MANAGEMENTAND BUDGET, WASHINGTON, DC 20603.

FACILITY NAME (1) DOCKET NUMBER (2) PAGE 3 0 5 0 0 0 1 OF

'"""'Engineered Safety Feature Actuation of Containment Instrument Air (CIA) er ress r EVENT DATE (6) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED 0))

%g NUMSSA ceo) rt<<tsrrx'DNTH MONTH DAY YFAR YEAR co~ SEQUENTIAL DAY YEAR FACILITYNAMES DOCKET NUMBER(SI NUMBEA 0 5 0 0 0 v

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LICENSEE CONTACT FOR THIS LER (12I NAME TELEPHONE NUMBER AREA CODE COMPLETE ONE LINE FOR EACH COMPONENT FAILURE OESCRIBEO IN THIS REPORT (13) r, c vcr et CAUSE SYSTEM COMPONENT MANUFAC. EPORTABLE R4 6 . r4 SYSTEM COMPONENT MANUFAC- EPORTABLE TO NPRDS ~~

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At 1700 hours0.0197 days <br />0.472 hours <br />0.00281 weeks <br />6.4685e-4 months <br /> on October 4, 1990, during the performance of activities associated with a Technical Specification Surveillance Channel Functional Test, a pressure loss occurred in the Containment Instrument Air (CIA) System. 'he pressure loss occurred when relief valve (CIA-RV-2) opened prematurely when pressure was increased in the system. The pressure decrease caused the safety-related part of the CIA system to be isolated and automatically placed the backup bottled nitrogen source into service. This action is considered an Engineered Safety Feature Actuation.

The root cause for this event was Management Programs, Work Practices, and Preventative Maintenance less than adequate. A contributing cause was an Equipment .

Design Deficiency and less than adequate procedures.

Corrective actions to prevent recurrence include a review of the installed equipment against design I.equirements, and a review of operations and maintenance procedures associated with this event. An evaluation of the Material Management System processes will also be performed.

The event posea no threat to the health and safety of either the public or plant personnel.

NRC Form 366 (569)

NRC FORM 366A (669)

LICENSEE EV

'PPROVED U.S. NUCLEAR AEGULATORYCOMMISSION T REPORT (LER)

OMB NO. 31500104 EXPIRES.'4/30/92 o IMATED BURDEN PER RESPONSE TO COMPLY WTH THIS INFORMATION COLLECTION REQUEST: 500 HAS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE AECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH (P430), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555, AND TO THE PAPERWORK REDUCTION PROJECT (3(504)104), OFFICE OF MANAGEMENTAND BUDGET, WASHINGTON, OC 20503.

FACILITY NAME (ll DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)

PZ+ SSOVENTIAL yA< 46VISION

? .4 NVM664 +49 NVM 64 I

Washin ton Nuclear Plant - Unit 2 0 5 0 0 0 39 90 0 3 0 1 oF 0 TEXT i// rr>>rP g>>ce /I rPI)rr/rrd, IIAI 4ddr)irrr>>l //RC %%drrrr 36643/ ()7)

Plant Con'ditions Power Level - 96%

Plant Mode - 1 On October 4, 1990, the safety-related portion of the Containment Instrument Air (CIA) System was actuated. Just prior to the actuation Plant Instrumentation and Control Technicians were performing Technical Specification Surveillance 7.4.5.1.21, ADS-Accumulator Backup Low Pressur e Alarm Division II-Channel Functional Test. This test is a monthly test to verify the proper operation of three Containment Instrument Air (CIA) pressure switches. The I8C Technicians found Pressure Switch 21B (CIA-PS-21B) in the tripped condition and immediately notified the Shift Manager as required by the procedure.

Plant Operators then initiated action to reset CIA-PS-21B. They knew a CIA pressure of approximately 160 psig would be required to reset CIA-PS-21B and since the pressure control valve for CIA (CN-PCV-10) was set to control at 150 psig specific action would be needed to accomplish this task. One operator was sent to the Nitrogen Storage Tank (CN-TK-1) located outside the power block where he established radio communication with the control room. One of the I8C Technicians was located at CIA-PS-21B at the 548 foot Level of the Reactor Building who was also in communication with the control room. The Control Room Supervisor then instructed the Plant Operator at CN-TK-1 to open the bypass valve (CN-V-34) around CN-PCV-10 two turns to pressurize the CIA system in an effort to reset CIA-PS-21B.

When the pressure was inc'reased in the CIA system it peaked at approximately 165 psig according to the computer trace measured by Pressure Transmitter CIA-PT-20.

This was enough pressure to open relief valve (CIA-RV-2) located on the Air Receiver (CIA-AR-1). The setpoint listed on the data sheet for CIA-RV-2 is 180 psig so it appears to have opened at a somewhat lower pressure. With the relief valve open the pressure in the CIA header dropped to the point where the safety-related part of CIA isolated and the Division II backup nitrogen supply was initiated. This action is considered an Engineered Safety Feature Actuation.

The safety-related part of the CIA provides the nitrogen supply to operate the Main Steam Safety Relief Valves (MSRVs) in the Automatic Depressurization System (ADS) mode of operation. The ADS is a portion of the backup Emergency Core Cooling System (ECCS) designed to quickly reduce reactor pressure in the unlikely event of failure of the High Pressure Core Spray (HPCS) system. The ADS is composed of seven specially designated MSRVs that provide rapid depressurization of the primary system. The safety-related part of the CIA system normally receives nitrogen from the non-safety-related part of the system via CIA-V-39A(B). The HAU devices are used to designate safety-related Division I and the UBH devices make up Division II. When a loss of pressure e is detected by Pressure Switches CIA-PS-39A(B) valves CIA-V-39A(B) are automatically closed. This isolation occurred at 1700 hours0.0197 days <br />0.472 hours <br />0.00281 weeks <br />6.4685e-4 months <br /> when the pressure dropped to 140 psig.

NRC F orrrr 366A (669)

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (64)9) APPROVED OMB NO.3)500104 E XPIR ES: 4/30/92 E IMATEO BURDEN PER RESPONSE TO COMPLY WTH THIS LICENSEE EVE T REPORT ILER) INFORMATION COLLECTION REQUEST) 50.0 HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH (P4)30), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555, AND TO 1ME PAPERWORK REDUCTION PROJECT (31500104). OFFICE OF MANAGEMENTAND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (I) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)

SEQUENTIAL REVISION NUMBER NUM EA Washington Nuclear Plant - Unit 2 397 90 0 2 3 0 1 3 pF 0 7 TEXT //I rrroro 4/>>oo /4 ror/vtrod, vro odd/dor>>//VRC Forrrr 36dr4 9/ ()2)

Following isolation the CIA system is designed to maintain the Division I and II safety-related headers at a nominal pressure of 150 psig using backup nitrogen bottles. A total of three signals are used to initiate backup nitrogen for the ADS. The signals are (1) CIA-PS-22A(B) 137 PSIG, (2) CIA-PS-21A(8) 140 PSIG, and (3) CIA-V-39A(B) closed as described above. These signals feed a two-out-of-three logic circuit which initiates the stepping programmers for the nitrogen bottles.

Programmer "A", CIA-PROG-1A, is initiated by the "AH logic and provides backup nitrogen to three ADS valves. Programmer HB", CIA-PROG-18, is initiated by the HB" logic and provides backup nitrogen to four additional ADS valves. At 1700 hours0.0197 days <br />0.472 hours <br />0.00281 weeks <br />6.4685e-4 months <br /> CIA-PROG-18 (Division II) was automatically initiated by the logic described above.

The pressure in the Division II header recovered to 150 psig by 1705 hours0.0197 days <br />0.474 hours <br />0.00282 weeks <br />6.487525e-4 months <br />. It should be noted that the accumulators for the ADS valves each have a check valve between the accumulator and the header where the relief valve is located. Thus, nitrogen pressure would have been available to operate the Division II ADS valves.

The pressure in the Division I part of the CIA system was maintained above 150 psig throughout this time period.

Once CIA-RV-2 reset the CIA header pressure returned to the normal value of 150 psig and both CIA-V-39A and 8 were reopened. At this time CIA-PS-218 was still in a tripped condition. CN-V-34 was then opened again (one half turn) to reset CIA-PS-218 allowing I8C to complete their surveillance.

Immediate Corrective Action The relief valve was closed allowing the CIA header pressure to reestablish at 150 psig at 1705 hours0.0197 days <br />0.474 hours <br />0.00282 weeks <br />6.487525e-4 months <br />. CIA valves CIA-V-39A and CIA-V-398 were then reopened to establish the normal configuration.

Further Evaluation and Corrective Action A. Further Evaluation

1. The actuation of the Division II portion of CIA is being reported per the requirements of 10CFR50.73(a)(2)( iv) as an "event or condition that resulted in manual or automatic actuation of any Engineered Safety Feature (ESF).....".

NRC Form 366A (64)9)

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION APPROVED OMB NO. 3(50010E (BJ)9)

EXPIRES: E/30/92 IMATED BURDEN PER RESPONSE TO COMPI.Y WTH THIS LICENSEE EV T REPORT {LER) INFORMATION COLLECTION REOUEST: 50/I HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH (F430), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555, AND TO 1HE PAPERWORK REDUCTION PROJECT (31504)OS), OFFICE OF MANAGEMENTAND BUDGET, WASHINGTON, 0020503.

FACILITY NAME (1) DOCKET NUMBER (2) 'LER NUMBER (6) PAGE (3)

'.";: SEOUENTIAL REVISION

'..Ir NUMBER NUMBER Washington Nucl ear Pl ant - Unit 2 p 5 p p p 3 9 7 9 0 0 3 OF 0 7 TEXT /// moro g>>oo /r roqlr/rod, IrJo oddlrror>>///RC Fonrr 36649/ ((7)

2. Further evaluation of the history of CIA-PS-218 revealed the following information. In 1986 the pressure switch was changed from a Barton instrument to a Static-0-Ring device (Design Change Package 85-0147-OA-29) to provide a narrower deadband. Since the operating pressure in the CIA header is normally 150 psig and the trip setpoint (decreasing) is 140 psig the deadband was specified (fngineering Specification No.

16961-0009-1) at 8 psig. The final test certificate provided with the shipment of switches indicated that the 8 psig deadband was achievable. A review of the test data associated with the work order that installed the switch (Maintenance Work Request AU6651) indicates CIA-PS-218 never met the design requirements. A Material Request and subsequent purchase order to the manufacturer was submitted for an alternate switch to meet the deadband requirements in late 1986. In early 1987 the vendor issued a Part 21 that included the model switch installed as CIA-PS-218. An engineering evaluation of the Part 21 notification indicated that the installed switches were adequate for the CIA application. To remedy the Part 21 concern the vendor offered a replacement model switch with a greater deadband. In March 1990, in response to the open purchase requisition, the vendor formally guaranteed a maximum 12 psig deadband, 4 psig above the desired level. After an engineering review of the deadband information, the evaluation revision record for the replacement model was updated to allow the use of the replacement model for CIA-PS-21A(B) due to the system operating margin. The Material Management System (MMS) was updated to allow that application. Three days later, on March 23, 1990, the evaluation revision record was updated to remove CIA-PS-21A(B) from the list of available plant applications but the MMS database was not revised at that time..

3. In May 1990 I8C Technicians withdrew a replacement switch from plant stores to change out.CIA-PS-218 due to a discrepancy discovered during a monthly surveillance'. As part of the withdrawal process for this application, a Material Verification Record (MVR) check in the MMS is required to validate the use of the equipment for the specific application. That check was executed on this withdrawal but since the MMS database had not been updated to reflect the record revision there was no flag to preclude withdrawal for the CIA-PS-218 application. The MMS database was updated in June 1990 to remove CIA-PS-21A(B) as a suitable application for this model.

4. CIA-PS-218 surveillance data from June 1989 to June 1990 indicates an average deadband of 12.76 psig. Surveillance data from July 1990 to October 1990 for the replacement model switch indicates an average deadband of 15.29 psig.

NRC Form 366A (6J)9)

NAC FORM 366A U.S. NUCLEAR REGULATOAY COMMISSION APPAOVED OMB NO. 3(504)04 (64)9)

EXPIRES: 4/30/92 MATEO BURDEN PER RESPONSE TO COMPLY WTH THIS LICENSEE EV T REPORT (LER) INFORMATION COLLECTION REQUESTI 503) HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS TEXT CONTINUATION AND REPORTS MANAGEMENT BRANCH (P4)30). U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, OC 20555, AND TO THE PAPERWORK REDUCTION PROJECT (31504104), OFFICE OF MANAGEMENTAND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (1) DOCKET NUMBER 12) LER NUMBER (6) PAGE (3)

SEOVENTIAL PPP REVISION YEAR NVMSER .A NVM ER Washington Nuclear Plant - Unit 2 0 s 0 o o 3 9 7 90 0 2 3 01 5 OF 0 7 TEXT /// mare epeoe /4 rer)rr/red, ace edd/rr'one/ HRC Form 36643/117)

5. A review of the Plant Technical/Engineering correspondence including Field Change Request (FCR) 02- 85-0147-0-01 dated October 24, 1986 shows a request was made to have Pressure Switches CIA-PS-21A(B) connected to the Bypass and Inoperable Status Indicators (BISI) similar to Pressure Switches CIA-PS-22A(B). This would provide an alarm in the control room if either of these switches is in the tripped condition. However, the request was outside the scope of the associated modification and a revision to the Plant Modification Request (PMR) was never submitted.

6. Plant Operators were using the general guidance of Plant Procedures PPM 1.3.1, Conduct of Operations to perform the operation associated with the reset of CIA-PS-21B.'hey were also familiar with the problem because the same thing had happened before and the same process had been successfully used to reset the switch.

7. Discussions were held with the Plant I8C Technicians on alternate methods of resetting CIA-PS-21B. A portable nitrogen source is available to locally pump up the switch since the current procedure calls for a pressure source including a nitrogen bottle and regulator. They pointed out this was not included in the present version of the procedure and they would be reluctant to do this without a procedure deviation or approved work request.

8. The root cause for this event was Management Programs and Work Practices less than adequate in that the MMS database was not updated allowing the installation of a switch with an excessive reset. A second root cause was a Preventative Maintenance deficiency in the relief valve testing program that led to the premature lift and blowdown of CIA-RV-2. A contributing cause was and Equipment Design Deficiency in that there is no annunciator to indicate a trip on CIA-PS-21A or CIA-PS-21B. A second contributing cause was less than adequate procedural guidance to verify reset of CIA-PS-21B after CIA isolations and no direction to allow local reset of CIA-PS-21B.

B. Further Corrective Action The system requirements along with the installed configuration of CIA-PS-21A(B) will be reviewed to determine system operation.'his review will include a review of the need for if improvements can be made in annunciation in the control room if CIA-PS- 21A(B) are in the tripped condition.

NAC Form 366A (SJ/9)

0 NRC FORM 366A (ISJ)9)

~ ~

t LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION V.S. NUCLEAR REGULATORY COMMISSION t APPROVED 0MB NO. 31500)04 EXPIRES: 4/30/92 ESTIMATED BURDEN PER RESPONSE TO COMP(.Y WTH THIS INFORMATION COLLECTION REQUESTI 500 HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS AND REPORTS MANAGEMENT BRANCH (P4)30). U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555, AND TO 1HE PAPERWORK REDUCTION PROJECT (31504)104), OFFICE OF MANAGEMENTAND BUDGET.WASHINGTON, DC 20503.

FACILITY NAME (1I DOCKET NUMBER (2) LER NUMBER (6I, PAGE (3)

SEQUENTIAL SEP~F REVISION NVMIIER ">rN NUMSER Washington Nuclear Plant - .Unit 2 o s o o o 39 9 0 0 3 0 1 6 OF 0 7 TEXT /I/ moro SPooo /4 rorlo/rrrd, o44 odditiono/l/RC Form 366r49/ (17)

2. Plant operating procedures will be reviewed to determine if changes need to be made to reset CIA-PS- 21A(B) if a pressure decrease takes place in the CIA system.

3. Surveillance Procedure 7.4.5. 1.21 will be reviewed to provide additional guidance on steps to be taken in the event a switch is found in a tripped condition.

4. CIA-RV-2 was tested to verify the proper relief pressure. The as found lift pressure was 169.6 psig. This was below the nameplate setpoint of pressure 180 psig.

5. An evaluation will be performed of the transmittal and MMS update process where procurement requirements or use controls are revised.

6. The relief valve testing program was upgraded to include specialized methods for testing air/gas relief valves.

Safety Si nificance This is no safety significance associated with this event. The accumulators for the ADS valves each have a check valve between the accumulator and the header where the relief valve is located. Thus, nitrogen pressure would have been available for initial automatic operation of the ADS valves. In addition, all conditions associated with CIA-PS-21B have put the plant in a safer condition. There was no threat to the health and safety of Plant personnel or to the public.

Similar Events The most recent LER associated with CIA was LER 90-022. This LER described an ESF actuation of CIA caused by depleting the Nitrogen Cryogenic Tank (CN-TK-1) during containment inerting. There is a high probability that CIA-PS-21B was placed in a tripped condition three days earlier during that event which ended on October 1, 1990.

There were two other recent LERs associated with loss of normal CIA pressure and ESF actuation of the safety-related portion of CIA. LER 90-005 describes the event that occurred when the normal CIA supply was lost due to a faulty non-safety-related circuit breaker. LER 90-018 describes the event that occurred on September 4, 1990 when a light fixture was inadvertently moved against the manual handle on relief valve CIA-RV-5B causing depressurization of the Division II portion of the system.

These events all occurred on the CIA system but do not appear to be related in any significant way expect as noted above.

NRC Form 366A (64)9V

NRC FORM 366A (64)9)

~ ~ I LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION U.S. NUCLEAR REGULATORY COMMISSION t APPROVED 0MB NO. 31504)104 EXPIRES: 4/30/92 ESTIMATED BURDEN PER RESPONSE TO COMPLY WTH THIS INFORMATION COLLECTION REQUEST'. 500 HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS AND REPORTS MANAGEMENT BRANCH IP4)30), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON. DC 20555, AND TO 1HE PAPERWORK REDUCTION PROJECT (3(S04)104), OFFICE OF MANAGEMENTAND BUDGET, WASHINGTON. DC 20503.

FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE 13)

YEAR SEQUENTIAL REVISION NUMBEII NUMBER Washington Nuclear Plant - Unit 2 o s o 0 o 3 9 7 90 0 2 30 1 7 oF0 7 TEXT fffmoro Spoco (I roqrrlrod, IrJo oddirforrol HRC Form 3664'4) (1 2)

EI IS Information Text Reference EI IS Reference Containment Instrument Air (CIA) LD CIA Relief Valve 2 (CIA-RV-2) LD RV CIA Pressure Switch 218 LD PS (CIA-PS-218)

Containment Nitrogen Pressure Control LK PCV Valve 10 (CN-PCV-10)

Nitrogen Cryogenic Tank (CN-TK-1) LK TK Containment Nitrogen Bypass Valve LK V (CN-V-34)

CIA Pressure Transmitter 20 (CIA-PT-20) LD PT CIA Receiver Tank (CIA-AR-1) LD TK Safety Relief Valves (SRVs) SB V Automatic Depressurization System (ADS) BG High Pressure Core Spr@ System (HPCS) BG CIA Valves 39A and 8 (CIA-V-39A(B)) LD V CIA Pressure Switches 39A and 398 LD PS (CIA-PS-39A(B))

C IA Pressure Switches 22A and 228 LD PS (CIA-PS-22A(8))

CIA Pressure Switch 21A (CIA-PS-22A) LD PS CIA Programers lA and 18 LD PMC (CIA-PROG-1 A(18 ) )

CIA Relief Valve 58 (CIA-RV-58) LD RV NRC Form 366A (64)9)