ML20196F947

Safety Evaluation Supporting Amend 143 to License NPF-1

ML20196F947
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Site:	Trojan File:Portland General Electric icon.png
Issue date:	06/16/1988
From:	Office of Nuclear Reactor Regulation
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ML20196F882	List: ML20196F876 ML20196F929 ML20196F947
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NUDOCS 8807050365
Download: ML20196F947 (3)

Text

/ UNITED STATES 8 $ NUCLEAR REGULATORY COMMISSION h  ; WASHINGTON, D. C. 20555

\...../

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT N0.143 TO FACILITY OPFRATING LICENSE N0. NPF-1 PORTLAND GENERAL ELECTRIC COMPANY THE CITY OF EUGENE, OREGON PACIFIC. POWER AND LIGHT COMPANY TROJAN NUCLEAR PLANT DOCKET N0. 50-344

1.0 INTRODUCTION

By letter dated February 17, 1988, Portland General Electric Company (PGE) requested a change to Trojan Technical Specification Section 3/4.3.3.10, "Radioactive Liquid Effluent Instrumentation," by adding two new instru-ments for monitoring steam generator blowdown system (SGBS) discharge, and by revising the operability and surveillance requirements for the existing SGBS effluent line instrumentation. These new instruments are being installed as part of a modification of the existing SGBS.

2.0 Discussion and Evaluation The Steam Generator Blowdown System (SGBS), a nonsafety-related system (with the exception of that portion from the steam generators to the outboard containment isolation valves), is used in conjunction with the chemical fced system and the process sampling system (PSS) to control the chemical composition of water in the steam generator (SG) shell within specified limits. One function of the SGBS is to effect isolation of the system and prevent further blowdown if an unacceptable level of radioactivity is detected in the SG shell side water by the PSS.

In the current system design, that portion of piping from the steam l generators to the outboard containment isolation valves is designated safety-related seismic Category I. When unacceptable radioactivity l levels are detected in the secondary side, SGBS blowdown is terminated by i

closure of the outboard containment isolation valves upon receipt of an i actuation signal from the SGB monitor, PRM-10, located on the SGB sample l line.

l As part of the modification of the SGBS, PGE proposed the addition of a l

new radiation monitor, PRM-17, downstream of the SGB Ion Exchangers, which would isolate SGB discharge to the Discharge and Dilution Structure (D&DS) and would also terminate blowdown by effecting closure of four 8807050365Bego g44 PDR ADOCK O PDR P

, -2 control valves (one valve located in each blowdown line between the outboard containment isolation valves and the SG Blowdown Tank), when an unacceptable level of radioactivity is detected. _ The existing SGB monitor, PRM-10, will also continue to be utilized for alarm and SGBS isolation. PRM-10 will isolate blowdown prior to the SGBS processing the fluid while PRM-17 will isolate blowdown and effluent discharge after the fluid has been processed. As such, PGE has proposed that Table 3.3-12 of the Technical Specification (TS) be revised to require that either PRM-10 or PRM-17 be operable, to provide automatic termi-nation of SG blowdown. The. current TS requires PRM-10 (the only monitor onthisline)tobeoperable.

The inoperability of PRM-10 does not affect the o)erability of any of the outboard containment isolation valves since t1eir operability require-ments are governed by TS Section 3/4.6.3, "Containment Isolation Yalves."

PRM-17 provides effluent monitoring dedicated to the SG blowdown flow path. Should SGBS discharge be routed to the D&DS, the liquid radwaste effluent monitor (PRM-9) will also be capable of providing effluent discharge isolation since its operability requirements will not be altered.

Based on the above, we find the proposed TS change regarding the opera-ability requirements of PRM-10 and PRM-17 to be acceptable.

Also, as part of the modification of the SGBS, PGE proposed the addition of a new effluent flow rate monitor, F1-4921, downstream of the SGB5 heat exchanger and blowdown pump. This new monitor is dedicated to monitoring SG blowdown.

An existing effluent flow rate monitor, FI-6715, is located in the discharge line to the D&DS since the current SGBS configuration directs its discharge to the plant discharge header. In the proposed modification of the SGBS, the normal path of SGBS discharge would be to the condenser, while the alternate discharge path would be to the D&DS. As such, PGE has proposed that Table 3.3-12 of the TS be revised to require that either FI-6715 or F1-4921 be operable to provide effluent flow rate monitoring capability. The current TS requires F1-6715 (currently the only monitor available to monitor effluent flow rate) to be operable.

Both flow rate monitors will perform the same functions. Therefore, the addition of the new effluent flow rate monitor provides a second monitor in the discharge line. Either of the monitors will be capable of providing flow rate data. The new flow rate monitor will provide remote indication I at a recorder and flow totalizer on the SGB control panel in the Turbine l Building.

Based on the above, we find the proposed TS change regarding the opera-bility requirements of F1-6715 and FI-4921 to be acceptable.

I l

The proposed surveillance requirements of TS Table 4.3-8 regarding the new monitors (PRM-17 and FI-4921) are also acceptable since they are identical to those which are applied to the current monitors (PRM-10 and FI-6715).

3.0 CONTACT WITH STATE OFFICIAL The NRC staff has notified the Oregon Department of Energy of the proposed issuance of this amendment along with the proposed detertnination of no significant hazards consider,ation. No coments were received.

4.0 ENVIRONMENTAL CONSIDERATION

This amendment involves a change in the installation or use of a facility component located within the restricted area cs defined in 10 CFR Part 20.

The staff has determined 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 previously publishad a proposed finding that the amendment involves no significant hazards consideration and there has been no public coment on such finding. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR $51.22(b), no environmental impact state-ment or environmental assessment need be prepared in connection with the issuance of the amendment.

5.0 CONCLUS10!{

Wehaveconcluded,basedontheconsiderationsdiscussedabove,that(1)there l is reasonable assurance that the health and safety of the be endangered by operation in the proposed manner, and (2)public such will net activities will be conducted in compliance with the Comission's regulations, and (3) the issuance of the amendment will not be inimical to the comon l defense and security or to the health and safety of the public.

PRINCIPAL CONTRIBUTOR:

T. Chan 1

Dated: June 16, 1988