ML20133P754

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Proposed Tech Specs,Increasing Min Water Level to Be Maintained in Condensate Storage Tank to 70%.Certificate of Svc Encl
ML20133P754
Person / Time
Site: Trojan File:Portland General Electric icon.png
Issue date: 10/29/1985
From:
PORTLAND GENERAL ELECTRIC CO.
To:
Shared Package
ML20133P732 List:
References
TAC-60095, NUDOCS 8511010171
Download: ML20133P754 (7)
v • d • e


Text

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LCA 134 .

o Attachment 1 Page 1 of 2 PLANT SYSTEMS CONDENSATE STORAGE TANK

' LIMITING CONDITION FOR OPERATION 3.7.1.4_ The condensate storage tank shall be OPERABLE with a minimum contained volume of 222,000 gallons of water.* l APPLICABILITY: MODES 1, 2, and 3.

ACTION:

With the condensate storage tank inoperable, within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> either:

a. Restore the condensate storage t'ank to OPERABLE status or be in HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, or i
b. Demonstrate the OPERABILITY of the Service Water System as a backup supply to the auxiliary feedwater pumps and restore the condensate storage tank to OPERABLE status within 7 days or be in NOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. .

SURVEILLANCE REQUIREMENTS N

4.7.1.4.1 The condensate storage tank shall be demonstrated OPERABLE at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by verifying the water level is within its limit when the tank is the supply source for auxiliary feedwater pumps.

4 4.7.1.4.2 The Service Water System shall be demonstrated OPERABLE at i least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by verifying that at least one Service Water System train is operating and that the Service Water System-feedwater isolation valves are either open or OPERABLE whenever the Service Water System is the supply source for the auxiliary feedwater pumps.

  • Until modifications to the Auxiliary Feedwater System, including alterations to prevent spurious low suction pressure trips for the safety-related auxiliary feedwater pumps, are completed a minimum condensate storage tank level of 70 percent (325,000 gallons) shall be maintained.

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LCA 134

- Attachment 1 Page 2 of 2 PLANT SYSTEMS BASES 3/4.7.1.4 CONDENSATE STORAGE TANK The OPERABILITY of the condensate storage tank with the minimum water volume ensures that sufficient water is available to maintain the RCS at HOT STANDBY conditions for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> with steam discharge.

at atmosphere. concurrent with total loss of offsite power. Tha minimum contained volume accounts for: (1) water volume required to be delivered

- to the steam generators (196,000 gallons), (2) unusable volume in the bottom of the condensate storage tank (16,000 gallons), and (3) instrument error (9,500 gallons), rounded off to 222,000 gallons.

Temporarily, a minimum volume of 325,000 gallons (70-percent indicated level) is being maintained in the condensate storage tank to reduce the likelihood of low suction pressure trips when both safety-related auxiliary feedwater pumps are started simultaneously. Following Auxiliary Feedwater System modifications that provide alternate means of preventing common mode failure of the safety-related auxiliary feedwater pumps due to loss of suction, and alterations to prevent spurious low suction pressure trips, a minimum CST level of 70 percent will no longer be required.

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UNITED STATES OF AMERICA I NUCLEAR REGULATORY COMMISSION l I

In the Matter of )  !

)

PORTLAND CENERAL ELECTRIC COMPANY, ) Docket 50-344 THE CITY OF EUGENE, OREGON, AND ) Operating License NPF-1 PACIFIC POWER & LIGHT COMPANY )

)

(TROJAN NUCLEAR PLANT) )

CERTIFICATE OF SERVICE I hereby certify that copies of License Change Application 134 to the Operating License for Trojan Nuclear Plant, dated October 29, 1985, have been served on the following by hand delivery or by deposit in the United States mail, first class, this 29th day of October 1985:

Mr. Lynn Frank, Director State of Oregon Department of Energy Labor & Industries Bldg. Rm 102 Salem OR 97310 Mr. Robert L. King Chairman of County Commissioners Columpla County Courthouse St. Helens OR 97051 yee G. A7 Zimmerman, Manager Nuclear Regulation Branch Nuclear Safety & Regulation Subscribed and sworn to before me this 29th day of October 1985.

Notary Public of Ore gn OMyCommission #

[

LCA 134 Page 1 of 2 REASON FOR CHANGE 1

Recent difficulties with the Auxiliary Feedwater (AFW) System have indi-cated that the safety-related AFW pumps are prone to low suction pressure trips on startup if the condensato storage tank (CST) level is less than 60 percent, particularly if both ? umps are started simultaneously. A.

Temporary Plant Test verified thr.t both pumps could be started simul-taneously from an automatic ini+,iation signal, and would continue to run and perform their design functions, if minimum CST level (when the pumps are started) was limited to 60 percent indicated. The minimum allowable level (for Modes 1, 2, and 3) was increased to 70 percent to account for instrument error and for the static head provided by the water in the suction pressure transmitter reference leg. From the Control Room Curves and Tables Manual, 70-percent level corresponds to a minimum contained volume of 325,000 gallons.

As stated in our letter of August 12, 1985, we do not consider this Technical Specification change to be necessary. A minimum CST level of 70 percent is being incorporated into Plant operating procedures as a limit below which one AFW pump will be declared inoperable, and the Action Statement of Technical Specification 3.7.1.2, Auxiliary Feedwater System will be implemented. Action Statement a of Technical Specifica-tion 3.7.1.2 requires that, with onc of the two safety-related AFW pumps inoperable, the inoperable pump must be restored 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 placed in hot shutdown within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

Submittal of this Technical Specification change (to a minimum CST level of 60 percent) was requested by the USNRC in your letter of September 13, 1985 (E. J. Butcher to B. D. Withers).

DESCRIPTION OF CHANGE Page 3/4 7-8. TTS 3.7.1.4. Condensate Storage Tank The minimum contained volume in the CST during operation in Modes 1, 2, and 3 is changed from 196,000 to 222,000 gallons. As described in the revised Bases for Technical Specification 3.7.1.4, the specification mandating 196,000 gallons does not account for instrument error and the .

unusable volume in the CST. A footnote is added to Technical Specifica-tion 3.7.1.4 explaining that an interim minimum CST level of 70 percent (325,000 gallons) will be maintained in the CST until modifications to the AFW System, including alterations to prevent spurious low suction pressure AFW pump trips, are completed.

Page B 3/4 7-2a. Bases 3/4.7.1.4 The Bases section for Technical Specification 3.7.1.4 has been expanded to identify the components of the 222,000 gallons minimum CST level. The interim minimum CST level of 70 percent (325,000 gallons) is also explained in the' revised Bases.

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LCA 134

' Page 2 of 2 SIGNIFIC_ ANT MAZARDS CONSIDERATION Ir. a letter to the NRC of August 12, 1985 (B. D. hithers to

E. J. Butcher), PGE has already conunitted to maintaining 160-percent.

level in the CST by administrative controls. As noted in that letter.

  • increasing the minimum operating level in the CST to 60 percent does not constitute an unreviewed safety question because the piobability of occurrence or the consequences of an accident or malfunction of equipment 1 important to safety previously evaluated in the safety analysis report is not increased. Raising the CST minimum water level to 60 percent decreases the probability and the consequences of an accident or malfunc-tion of equipment important to safety. A level of 60 pe. cent provides greater assurance that both AFW pumps will automatical'.y start and operate, and provides a greater volume of water in t*se CST for heat removal. These discussions also apply to increasing the minimum operating level in the CST to 70 percent.

f The possibility for an accident or malfunction of a different type than any evaluated previously in the safety analysis report is not created by

+ increasing the minimum CST level to 70 percent. A minimum level of 70 percent provides additional conservatism and does not create the possibility for an accident or a malfunction of a different type than evaluated previously.

Also, the margin of safety defined in the basis for any Technical Speci-fication has not been reduced by this increase in minimum CST level. The margin of safety is increased by this change.

Based on the above, this Technical Specifiestion change does not involve a significant hazards consideration.

SAFETY / ENVIRONMENTAL EVALUATION Safety and environmental evaluations were performed as required by 10 CFR 50 and the Trojan Technical Specifications. This review deter-mined that an unreviewed safety question does not exist since Plant operations remain consistent with the Updated FSAR, adequate surveillance is maintained, and there is no conceivable impact upon the environment.

SCHEDULE CONSTDERATIONS Mone.

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'- LCA 134 ,

Attachment 1 Page 1 of 2 PLANT SYSTEMS CONDENSATE STORAGE TANK LIMITING CONDITION FOR OPERATION 3.7.1.4 The condensate storage tank shall be OPERABLE with a minimum contained volume of 222,000 gallons of water.* l APPLICABILITY: MODES 1, 2, and 3.

ACTION:

With the condensate storage tank inoperable, within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> either:

a. Restore the condensate storage tank to OPERABLE status or be in HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, or
b. Demonstrate the OPERABILITY of the Service Water System as a backup supply to the auxiliary feedwater pumps and restore the condensate storage tank to OPERABLE status within 7 days or be in HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

SURVEILLANCE REQUIREMENTS 4.7.1.4.1 The condensate storage tank shall be demonstrated OPERABLE at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by verifying the water level is within its limit when the tank is the supply source for auxiliary feedwater pumps.

4.7.1.4.2 The Service Water System shall be demonstrated OPERABLE at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by verifying that at least one Service Water System train is operating and that the Service Water System-feedwater isolation valves are either open or OPERABLE whenever the Service Water System is the supply source for the auxiliary feedwater pumps.

  • Until modifications to the Auxiliary Feedwater System, including alterations to prevent spurious low suction pressure trips for the safety-related auxiliary feedwater pumps, are completed a minimum condensate storage tank level of 70 percent (325,000 gallons) shall be maintained.

f l l TROJAN-UNIT 1 3/4 7-8

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LCA 134

    • Attachment 1

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. Page 2 of 2 i

PLANT SYSTEMS BASES 3/4.7.1.4 CONDENSATE STORAGE TANK The OPERABILITY of the condensate storage tank with the minimum water volume ensures that sufficient water is available to maintain the RCS at HOT STANDBY conditions for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> with steam discharge at atmosphere concurrent with total loss of offsite power. The minimum contained volume accounts for: (1) water volume required to be delivered to the steam generators (196,000 gallons), (2) unusable volume in the bottom of the condensate storage tank (16,000 gallons), and (3) instrument error (9,500 gallons), rounded off to 222,000 gallons.

Temporarily, a minimum volume of 325,000 gallons (70-percent indicated level) is being maintained in the condensate storage tank to reduce the likelihood of low suction pressure trips when both safety-related auxiliary feedwater pumps are started simultaneously. Following Auxiliary Feedwater System modifications that provide alternate means of preventing common mode failure of the safety-related auxiliary feedwater pumps due to loss of suction, and alterations to prevent spurious low suction pressure trips, a minimum CST level of 70 percent will no longer be required.

TROJAN-UNIT 1 B 3/4 7-2a

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