ML20215K130

Provides Addl Info Re Verification & Validation of Plant Safety Monitoring Sys Software Components Associated W/ safety-related Reg Guide 1.97 Variables

ML20215K130
Person / Time
Site:	Beaver Valley
Issue date:	04/30/1987
From:	Sieber J DUQUESNE LIGHT CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
RTR-REGGD-01.097, RTR-REGGD-1.097 2NRC-7-101, TAC-64577, NUDOCS 8705110086
Download: ML20215K130 (7)

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M 2NRC-7-101 Beaver Valley No. 2 Unit Project Organization Telecopy ( 1 ) 3 Ext.160 S.E.G. Building P.O. Box 328 April 30, 1987 Shippingport, PA 15077 United States Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555

SUBJECT:

Beaver Valley Power Station Unit No. 2 Docket No. 50-412 Plant Safety Monitoring System - Verification & Validation Gentlemen:

In a letter dated February 11, 1987, Duquesne Light Company (DLC) was requested to provide information regarding verification and validation of Plant Safety Monitoring System (PSMS) software components which are associated with safety-related Regulatory Guide 1.97 variables. The Staff's request (paragraph

1) begins by pointing out that BVPS-2 displays inadequate core cooling (ICC) and other RG 1.97 Category 1 variables via the PSMS. Presumably this is the basis for the subsequent information requests. Please note that BVPS-2 views ICC as a Category 2 v ari able. The following information is provided in response to the staff's request.

1. DLC was requested to implement a verification and validation plan in accordance with ANSI /IEEE-ANS-7-4.3.2 and to incorporate Staff comments from audit reports of the South Texas Project. (Paragraph 2 of the Staff request)

Response

T h e Staff's request is contrary to Regulatory Guide 1.152 Section D which indicates that this guide will not be applied to license applications under Staff review in 1985. Since the new Staff position identified in the Staff's letter is not uniquely applicable to BVPS-2, CRGR review of this issue is required prior to further imposition.

ANSI /IEEE-ANS-7-4.3.2 has not been applied and is not applicable to t h e BVPS-2 PSMS for the following additional reasons:

0 8705110086 870430 I \

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United States Nuclear Regulatory Commission Plant Safety Monitoring System - Verification & Validation Page 2 l

a. PSMS Design and Application Basis Since the MCB is the primary source of control information, the primary function of the PSMS is to provide displays which are diverse or redundant to the Main Control Board for safety-related The PSMS is a Class lE design and is given

! R.G. 1.97 parameters.

the required degree of design review, factory testing and site testing to ensure that it meets its design function. The Class 1E design provides redundant circuits that can be used to cross-check for proper indication and provides the capability of flagging out of tolerance data, thus achieving the system accuracy requirements of a Class lE design. Those variables whose primary display i station is the PSMS are given in Table 1. Table 1 also presents a i listing of those variables for which the PSMS serves diverse or redundant indication.

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b. BVPS-2 Station Control Philosophy The BVPS-2 station control philosophy is that the operators will utilize the Main Control Board (MCB) indication as the primary source of control information. Referring to Table 1 attached, it can be seen that seven of the variables (15 total listed) are diverse or redundant displays on the PSMS with the primary display location being the MCB. It is to be noted that those variables required for normal plant operations are displayed on the MCB.

Several of the variables (e.g., RCS pressure) displayed on the PSMS serve only to resolve ambiguity between the installed MCB indicators. For those variables that exist only on the PSMS (e.g.

RVLIS), DLC considers the Class 1E design and environmental quali-fication of those systems satisfy the requirements for use during R.G. 1.97 postulated conditions.

c. DLC considers that the imposition of a V&V program in accordance with ANS 7-4.3.2 would not result in a more dependable system and only serve the same purpose as design reviews, factory testing and site testing. The design review and factory testing are canplete and the site testing is nearly complete.

2. In the event that DLC does not plan to complete its evaluation of PSMS software adequacy by the projected licensing date, DLC was requested to make connitments similar to the Vogtle project, describe the state of completion for the evaluation, and provide an expected completion date for the evaluation. (Paragraph 3 of the Staff request) t

. United States Nuclear Regulatory Commission Plant Safety Monitoring System - Validation & Verification Page 3

Response

Having contacted Vogtle project staff, DLC is unable to determine the regulatory basis for the Vogtle commitments and cannot determine whether circumstances which compelled Georgia Power Company to make those conmitments are applicable to BVPS-2 as well. In the event that the BVPS-2 PSMS software evaluation is not complete prior to exceeding 5 percent power, DLC will describe to the Staff the current state of completion of its evaluation, justification for specific aspects of the program which are incomplete, and expected completion dates.

DLC's evaluation is planned to be complete prior to exceeding 5 per-cent power.

3. DLC was requested to specifically identify Category 1 RG 1.97 vari-ables displayed on the PSMS and whether indications independent of PSMS are available. (Paragraph 4 of the Staff request)

Response

This information is provided in the attached Table 1.

4. In the event that DLC has not completed its software evaluation prior to exceeding 5 percent power, DLC is asked to commit to weekly checks of PSMS indications against other available diverse indications. DLC is also requested to appropriately control use of PSMS information by the operators in the interim to prevent reliance on faulty informa-tion. (Paragraph 4 of the Staff request)

Response

DLC will consider these items in requesting a schedule extension beyond 5 percent power. Refer to request item 2 discussed earlier.

5. For those variables which do not have indications diverse from the PSMS DLC is requested to commit to make instructions available to the operators on how to determine the information by an alternate method independent of the PSMS if the PSMS displayed information is unavail-able or suspect as indicated by the above weekly checks. The alter-nate methods to be used should be clearly described. This request applies only if DLC's evaluation of PSMS software for these particular variables is not complete prior to exceeding 5 percent power. (Para-graph 5 of the Staff request)

United States Nuclear Regulatory Commission Plant Safety Monitoring System - Verification & Validation Page 4

Response

DLC will consider these items in requesting a scheule extension beyond 5 percent power. Refer to request item 2 discussed earlier.

DLC believes that the BVPS-2 PSMS sof tware will have been demonstrated to be adequate upon completion of testing now in progress. Westinghouse, the system vendor, is in full support of the project's technical position on this matter. In accordance with NUREG BR-0073, please include a clear description of the regulatory basis for any future requests regarding this subject so that DLC may adequately address your concerns.

! DUQUESNE LIGliT COMPANY By J A J. D. Sieber

/Vice President Nuclear JGP/ijr NR/JGP/PSMS/VV Attachment AR/NAR cc: Mr. P. Tam, Project Manager (w/a)

Mr. J. Beall, NRC Sr. Resident Inspector (w/a)

Mr. L. Prividy, NRC Resident Inspector (w/a)

INPO Records Center (w/a)

NRC Document Control Desk (w/a) l l

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United States Nuclear Regulatory Commission Plant Safety Monitoring System - Verification & Validation Page 5 COMMONWEALTH OF PENNSYLVANIA )

) Ss:

COUNTY OF BEAVER )

On this 3 dA day of _w / l' . _,

/fM/_,beforeme,a Notary Public in and for said Coinmonwealth and County, personally appeared J.

D. Sieber, who being duly sworn, deposed and said that (1) he is Vice President of Duquesne Light, (2) he is duly authorized to execute and file the foregoing Submittal on behalf of said Company, and (3) the statements set forth in the Submittal are true and correct to the best of his knowledge.

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U a h!w!bdL Not4ry Public ELVA G. LESONDAK, NOTARY FUBLIC -

SHIPPINGPO:iT, BEAVER COUNTY MY COMMISSION EXPIRES OCTOBER 20,1990 i

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TABLE 1 l

l CROSS REFERENCE OF CLASS lE SIGNRLS DISPLAYED ON PSMS ,

l Variable R.G. Primary Displayed 1.97 Display MCB Category Location Indication Remarks on PSMS See Note 1 RCS Pressure 1 MCB (Main 2RCS*PI440, 441 (PT442) Control Board)

RCS TH (WR) 1 MCB 2RCS*TI413, 423, i

433 l

1 MCB 2RCS*TI410, 420, RCS Tc (WR) 430 Steam-Line 1 MCB 2 MSS *PI475, 476, l

Pressure 485, 486, 495, 496 PRI Plant 1 MCB 2FWE*LIl04Al, DWST LVL 104A2 (LT104A3)

N/A Values can be determined from measured voltages.

Core Exit 1 PSMS Thermocouple 2 PSMS N/A Values can be calculated using existing signals.

RCS Sub-Cooling Neutron Flux 1 PSMS N/A NIS Ind. on MCB and PSMS indications are from independent systems. Values can be cross-checked .

RVLIS 2 PSMS N/A during normal operation.

Containment 1 MCB HCS*HIl00A,B Hydrogen Concentra-tion 4 I I

~ TABLE 1

CROSS REFERENCE OF CLASS 1E SIGNALS DISPLAYED ON PSMS .

! Variable R.G. Primary I Displayed 1.97 Display MCB on PSMS Category Location Indication Remarks Containment 1 MCB 2LMS*PI950, 951, Pressure 952, 953

! (LMS*PT106A, 106B) i Pri. Safety 2 P!MS N/A Valve Status (2RCS*RV551A 5518,551C)

S/G Ssafety 2 PSMS N/A

. Valve Status (2 MSS *SV101-105A,B,C)

(15 total)

I 2CCP-PT145A,B,C CCW Header 2 PSMS MCB Indications are non-IE but can be used for i Pressure comparison.

(2CCP*PT105A B,C)

CCW Header 2 PSMS 2CCP-TIl00A,B,C MCB Indications are non-IE but can be used for Temperature comparison.

(2CCP*TE130A l 1308,130C)

I NOTE 1 - Where a mark no is given for the PSMS, the circuit is unique to PSMS. Where not so noted, the circuits are common with other control room circuits.

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