ML20138C747

Forwards Addl Info Re Generic Ltr 83-28,Item 1.2, Post-Trip Review Data & Info Capability, Per 851107 Request. Parameters for Containment Isolation,Control Rod Position & Steam Generator Pressure Part of Reactor Trip Rept

ML20138C747
Person / Time
Site:	Callaway
Issue date:	12/11/1985
From:	Schnell D UNION ELECTRIC CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
References
GL-83-28, ULNRC-1225, NUDOCS 8512130081
Download: ML20138C747 (6)

Text

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asu UNION ELECTINC COM%NY December 11, 1985 1901 Grotiot Street St. Louis Donoid F. SchneN Vice President Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation ULNRC-1225 U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Dear Mr. Denton:

DOCKET NUMBER 50-483 UNION ELECTRIC COMPANY CALLAWAY PLANT RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING GENERIC LETTER 83-28, ITEM 1.2 " POST-TRIP REVIEW DATA AND INFORMATION CAPABILITY"

References:

1. Youngblood to Schnell letter dated November 7, 1985

2. ULNRC-763 dated March 12, 1984 Reference one transmitted the subject request for additional information. The attachment provides Union Electric's response to this request. This response supplements the information submitted via reference two.

Very truly yours, f1t Donald F. Schnell i GGY/lw Attachment

$Y 8512130001 DR 851211 '

p ADOCK 05000403 Il l PDR l l I

Moding Address: RO Box 149, St Louis MO 63166

STATE OF MISSOURI )

) SS CITY OF ST. LOUIS )

Donald F. Schnell, of lawful age, being first duly sworn upon oath says that he is Vice President-Nuclear and an officer of Union Electric Company; that he has read the foregoing document and knows the content thereof; that he has executed the same for and on behalf of said company with full power and authority to do so; and that the facts therein stated are true and correct to the best of his knowledge, information and belief.

By 5 __

Donald F. Schnell Vice President Nuclear SUBSCRIBED and sworn to before me this //I day of Jgm/w', 1986I 2 tdd/9 4 BARGARA J.!PTAFF[

NOTARY PUGUC, STATE CF btfS500R1 MY COW:SSION EXPIRES APRIL 22,190 sT. Louis county

cc: Gerald Charnoff, Esq.

Shaw, Pittman, Potts & Trowbridge 1800 M. Street, N.W.

Washington, D.C. 20036 Nicholas A. Petrick Executive Director SNUPPS 5 Choke Cherry Road Rockville, Maryland 20850 C. W. Hehl Division of Projects and Resident Programs, Chief, Section lA U.S. Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, Illinois 60137 i Bruce Little Callaway Resident Office U.S. Nuclear Regulatory Commission RRil Steedman, Missouri 65077 Tom Alexion Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Mail Stop P-316 7920 Norfolk Avenue Bethesda, MD 20014

r RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING GENERIC LETTER 83-28, ITEM 1.2

" POST-TRIP REVIEW DATA AND INFORMATION CAPABILITY"

1. . Staff Position: Based upon the information contained in the submittal [ Reference 2], all of the parameters specified in Part 2 of this report [ Reference.1] that should be recorded for use in a post-trip review are not recorded.

Response

A. The following parameters were noted as not being available on the Sequence of Events Recorders:

(i) Containment Isolation

1. The containment. isolation signal phase A (CISA) initiates the Radiation Monitoring System (RMS). The time of CISA initiation can be retrieved from the time recorded on RMS.

2. As a part of Callaway Operations Department Procedure ODP-ZZ-00015, Reactor Trip Review, and Emergency Operating Procedure E-0, Reactor Trip or Safety Injection, containment isolation is verified by the operator and corrective actions are performed, as needed. Systems / components with inadequate performance are noted in the Reactor Trip Report.

-(ii) Control Rod Position

1. The NSSS computer Sequence of Events (SOE)

Recorder monitors reactor trip breaker position, but it does not have the capability to monitor analog control rod positions.

2. . There is a sign off block in the Reactor Trip Review procedure to verify that all

. equipment performed as required.

Verification of " rod bottom lights lit" on

.the Digital Rod Position Indication Panel RLO22 is the first step of Emergency Operating Procedure E-0, Reactor Trip or Safety Injection.

3. The NSSS computer SOE and Time History Recorders and the BOP computer Time History Recorder monitor the source range, intermediate range, and power' range detectors. These parameters can be used as an indication that the rods have dropped.

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4. The control rod position strip chart recorder on Panel RLO22 provides verification that the rods have dropped.

(iii) Steam Generator Pressure

1. The NSSS computer Time History Recorder receives the analog signals from three channels of steam generator (SG) steam pressure downstream of the steam generator, for all four loops. Further, as identified in Table 1.2.1-1 of Attachment I to Reference 2, one channel of SG steam line pressure is recorded by the NSSS computer SOE recorder for each loop.

2. The BOP computer Time History Recorder receives the analog signals from three channels of SG steam pressure downstream of I

the SG, for all four loops.

3. A strip chart recorder monitors the SG pressure signals from one channel for each loop.

4. This combination of recorders and redundancy provides ade.quate monitoring of SG pressure during a transient.

(iv) PORV Position

1. Even though the SOE Recorders do not record this parameter, the BOP computer Time 4 History Recorder does contain these valve

positions (open/close). In addition, PORV change of status can be obtained from the pressurizer pressure strip chart recorder.

Even though the SOE Recorders do not contain the parameters listed above, with the exception of SG pressure, they are all recorded and would be a part of the Reactor Trip Report to be analyzed prior to restart. This information can be utilized to adequately reconstruct the accident scenarios presented in Chapter 15 of the SNUPPS Final Safety Analysis Report (FSAR) and is sufficient to establish that the plant remained within the design envelope for the appropriate 4

accident conditions.

d 0

3/3 B. The following parameter was noted as not being available on either the SOE cr Time History Recorders:

(i) Primary System Flow The primary system flow parameter is recorded by the following:

1. The NSSS computer Sequence of Events (SOE)

Recorder receives the following signals:

reactor coolant low flow in two or more loops plus permissive P7 (causes reactor trip) and reactor coolant low flow in any loop plus permissive P8 (causes reactor trip.)

2. The NSSS computer Time History Recorder receives the analog signals from three channels of each reactor coolant loop flow parameter (all four loops) .

3. The BOP computer Time History Recorder receives the analog signals from three channels of each reactor coolant loop flow parameter (all four loops) .

4. This information was submitted in Tables 1.2.1-1, 1.2.2-1, and 1.2.2-2 of Attachment 1 to Reference 2. This combination of parameter recordings is sufficient to determine which loop caused a reactor trip and the time of reactor trip.

2. Staff Position: Time History Recorders, as described in the submittal [ Reference 2], do not meet the minimum performance characteristics [specified in Part 2 of Reference 1].

Response:' The NSSS computer Time !!istory Recorder will scan the data points two minutes before the event to three minutes after. The BOP computer Time !!istory Recorder will scan the data points five minutes before the event to ten minutes after. The duration of the NSSS Time Ilistory (two minutes before trip and three minutes af ter trip) provides sufficient information to adequately assess the cause of unscheduled reactor shutdowns. Further, each of the parameters listed on Table 1.2-1 of Reference 1 as desirable PWR parameters for post-trip review for the Time IIistory Recorder are monitored by the BOP computer Time History Recorder and therefore includes the five minutes before the event to ten minutes after the event duration.