ML20212J383

Safety Evaluation Supporting Amend 50 to License DPR-34

ML20212J383
Person / Time
Site:	Fort Saint Vrain
Issue date:	02/26/1987
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20212J298	List: ML20212J293 ML20212J317 ML20212J383
References
TAC-60421, NUDOCS 8703090017
Download: ML20212J383 (4)

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UNITED STATES 8  % NUCLEAR REGULATORY COMMISSION j

$ $ WASHINGTON, D. C. 20066

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 50 TO FACILITY OPERATING LICENSE NO. DPR-34 PUBLIC SERVICE COMPANY OF COLORADO FORT ST. VRAIN NUCLEAR GENERATING STATION DOCKET NO. 50-267 1.0 BAC GROUND By etters dated June 4 and December 19, 1986, Public Service Company of Co1 erado, the licensee for Fort St. Vrain, submitted proposed Technical Spv:ifications changes for the Steam Line Rupture Detection and Isolation Sy' tem (SLRDIS). Additional information was provided in the licensee's le.ter dated October 27, 1986., It should be noted that the December 19, li16 submittal was essentially a new application by the licensee in orporating several changes requested by the NRC staff. The specific chtiges made in this new submittal clarify the actions to be taken by the oper 'or when one or more of the SLRDIS instrument channels become inoper. +.f ve. It also reduces the time in which the operator must take action a 'd adds provision for daily checks of the instrument channels.

The follos ing is the staff evaluation of the licensee's proposal.

2.0 EVALUATION In the June 4 and December 19, 1986 submittals, the licensee proposed to remove all references to the existing steam pipe rupture detection system (SPRDS) from the plant Technical Specifications and to substitute for them requirements on the operability and surveillance of SLRDIS. This change was made since the SLRDIS replaces the SPRDS as the primary means relied upon to ensure safe plant shutdown and mitigation of design basis secondary side high energy line breaks in both the reacter and turbine buildings. Specific proposed Technical Specifications'.' hanges c are as follows: y 8703090017 870226 DR ADOCK O g7

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1. LCO 4.4.1

a. Table 4.4-2. Page 4.4-4, " Instrument Operating Requirements for Plant Protective System, Loop Shutdown."

The licensee deleted all references to the SPRDS which is being replaced by the SLRDIS. SPRDS deletions were also made on pages 4.4-8, 4.4-9, 4.4-12, 4.4-12a , 5.4-6 and 5.4-7.

b. Table 4.4-3, Page 4.4-6a, " Plant Protective System, Trip Setpoints -

Circulator Trip."

.The licensee added the above tables in order to incorporate the SLRDIS rate-of-rise setpoints for trip of the helium circulators, nominally between 52.3 and 52.8*F per minute.

c. Table 4.4-3(continued),Page4.4-6b,"PlantProtectiveSystem.

Operability Requirements - Circulator Trip."

The licensee incorporated these additions in order to specify the limiting conditions for operation with less than a full complement of operating SLRDIS channels and/or secondary side isolation valves actuated by SLRDIS. The action statements require the following:

(1) Action Statement 1: With only 7 operable SLRDIS channels in either or both buildings, the inoperable channel (s) is (are) to be placed in bypass within one hour or the plant power is to be reduced to 2% within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. In the event of continued operation, the inoperable channel (s) must be returned to operable status within seven days or plant power reduced to below 2% within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

(2) Action Statement 2: With only 6 operable SLRDIS channels in either or both buildings, the inoperable channels are to be placed in bypass within I hour. The plant level shall be reduced to below 2% within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> whether the inoperable channels have been placed in bypass or not.

Operation at power may continue if at least 7 operable channels are placed in service in accordance with the provisions of Action Statement 1, above.

(3) Action Statement 3: With the number of inoperable SLRDIS channels in excess of that permitted in Action Statements 1 and 2, the plant power level is to be reduced to below 2% within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

(4) Action Statement 4: With a single inoperable SLADIS valve or valve circuit, the inoperable valve or valve circuit

must be returned to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, or the plant power level. reduced to below 2% within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

5) Action Statement 5: With two or more inoperable SLRDIS valves or valve circuits, the inoperable valves or valve circuits must be restored to operable status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or the plant power level reduced to below 2% within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

2. Basis for LCO 4.4-1, Page 4.4-12, 12a, 12b and 13.

The 1.icensee amended the basis for Technical Specification LC0 4.4-1 by deleting references to SPRDS and adding discussion relating to SLRDIS as a substitute for performing comparable high energy line break mitigation functions.

3. Basis for SR 5.4.1

a. Page 5.4-2 The licensee amended the basis for SR 5.4.1 to address the SLRDIS surveillance requirements,

b. Table 5.4-3 (continued) Page 5.4-10a, " Circulator Trip System Instrumentation Surveillance Requirements."

The licensee added the surveillance requirements for the four SLRDIS loops, two in the reactor building, and two in the turbine building. These requirements include:

(1) Channel checks - daily (2) Channel calibrations, channel functional tests and actuation logic tests at least once during each refueling cycle, not to exceed 18 months.

It should be noted, further, that each SLRDIS logic rack contains a microprocessor which automatically monitors internal components and critical circuitry on a continuous basis. A trouble condition will cause 1) the system nomal indicator to turn off, 2) the annunciator output contacts to transfer if the trouble condition is initiated by a detection rack, 3) the event to be logged on system printers, and 4) trouble audible alams to sound. Actuation logic tests will include verification of a response time of 7.1 seconds or less.

Based on the above review of the proposed SLRDIS Technical Specifica-tions changes, the staff concludes that they are consistent with the Standard Technical Specifications for safety-related engineering safety feature actuation systems and provide adequate assurance that

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the SLRDIS can reliably perfom its intended safety function. The above indicated Technical Specifications changes are, therefore, acceptable.

4.0 ENVIRONMENTAL CONSIDERATION

The amendment relates to changes in recordkeeping, reporting or administrative procedures or requirements. The staff has detemined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has prev'iously issued a proposed finding that this amendment involves no significant hazards consideration and there has been no public connent on such finding. Accordingly, this amendment meets the eli for categorical exclusion set forth in 10 CFR 551.22(c)(gibility 9). Pursuant criteria to 10 CFR 551.22(b), no Environmental Impact Statement or Environmental Assessment need be prepared in connection with the issuance of this amendment.

5.0 CONCLUSION

The Comunission made proposed determinations that the amendment involves no significant hazards consideration which were published in the Federal Register on July 30, 1986 (51 FR 27288), and January 14, 1987 (52 FR 1556), and consulted with the State of Colorado. No public comments were received, and the State of Colorado did not have any connents.

• We have concluded, based on the considerations discussed above, that:

(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Commission's regulations and the issuance of this amendment will not be inimical to the comanon defense and security or to the health and safety of the public.

Dated: February 26, 1987 Principal Contributors: N. Wagner, DPWRL-B P. Shemanski, DPWRL-B

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