ML042740577

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Proposed Change to Technical Specification Surveillance Requirement 4.7.1.6, Atmospheric Steam Relief Valves
ML042740577
Person / Time
Site: South Texas  STP Nuclear Operating Company icon.png
Issue date: 09/27/2004
From: Jordan T
South Texas
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
NOC-AE-04001769
Download: ML042740577 (14)
v • d • e


Text

Nuclear Operating Company South TrcisProctkctrlc GF nc-rk in8Sltaion PO. ar 282 Jdsvrth Tms 77483 a

September 27, 2004 NOC-AE-04001769 1 OCFR50.90 U. S. Nuclear Regulatory Commission Attention: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852 South Texas Project Units 1 and 2 Docket Nos. 50-498 and 50-499 Proposed Change to Technical Specification Surveillance Requirement 4.7.1.6.

"Atmospheric Steam Relief Valves" STP Nuclear Operating Company (STPNOC) is submitting the attached proposed change to Technical Specification (TS) Surveillance Requirement 4.7.1.6, "Atmospheric Steam Relief Valves." The purpose of this change is to alleviate the entry into a technical specification action statement for a condition not required by the safety analysis. The proposed change would revise the Operating Licenses to provide consistency between TS surveillance requirement 4.7.1.6 and TS 3.3.5.1 regarding atmospheric steam relief valve instrumentation controls.

The STPNOC Plant Operations Review Committee has reviewed and concurred with the proposed change to the Technical Specifications.

In accordance with 10 CFR 50.91(b), STPNOC is notifying the State of Texas of this request for license amendment by providing a copy of this letter and its attachments.

STPNOC requests approval of the proposed amendment by September 1, 2005. Once approved, the amendment will be implemented within 30 days to allow time for distribution and procedure changes.

There are no new commitments in this letter.

STI: 31772852

i NOC-AE-04001769 Page 2 If there are any questions regardirg the responses, please contact Mr. S. M. Head at (361) 972-7136 or me at (361) 972-7902.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on Sep4l 274 2c04-.

date Vice President, Engineering

& Technical Services kjtl Attachments:

1. Description of Changes and Safety Evaluation
2. Annotated Technical Specification Page
3. Revised Technical Specification Page

NOC-AE-0400 1769 Page 3 cc:

(paper copy)

(electronic copy)

Bruce S. Mallett Regional Administrator, Region IV U. S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, Texas 76011-8064 U. S. Nuclear Regulatory Commission Attention: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852 Richard A. Ratliff Bureau of Radiation Control Texas Department of Health 1100 West 49th Street Austin, TX 78756-3189 Jeffrey Cruz U. S. Nuclear Regulatory Commission P. O. Box 289, Mail Code: MN 16 Wadsworth, TX 77483 A. H. Gutterman, Esquire Morgan, Lewis & Bockius LLP L. D. Blaylock City Public Service David H. Jaffe U. S. Nuclear Regulatory Commission R. L. Balcom Texas Genco, LP C. A. Johnson AEP Texas Central Company Jon C. Wood Matthews & Branscomb C. M. Canady City of Austin Electric Utility Department 721 Barton Springs Road Austin, TX 78704

NOC-AE-0400 1769 Attachment I Description of Changes and Safety Evaluation

NOC-AE-04001769 Page I 1.0 Description This letter is a request to amend Operating License NPF-76 for Unit 1 and Operating License NPF-80 for Unit 2. The purpose of this change is to alleviate the entry into a Technical Specification (TS) action statement for a condition not required by the safety analysis. The proposed change would revise the Operating Licenses to provide consistency between TS Surveillance Requirement (SR) 4.7.1.6 and TS 3.3.5.1 regarding atmospheric steam relief valve instrumentation controls.

2.0 Proposed Change The STP Nuclear Operating Company (STPNOC) proposes to change SR 4.7.1.6 to add a footnote that clarifies that the SR for the automatic controls of the atmospheric steam relief valve is only applicable in Modes 1 and 2. The proposed surveillance would read as shown below.

4.7.1.6 Each atmospheric relief valve shall be demonstrated OPERABLE prior to startup following any COLD SHUTDOWN of 30 days or longer or following any refueling shutdown, by verifying that all valves will open and close fully by operation of automatic# and manual controls.

with footnote # reading

  1. Required to be met for automatic controls only in MODES 1 and 2 The revised TS is provided in Attachment 3. The TS Bases should not require revision since the footnote is self-explanatory. The current TS Bases discuss the operability requirements for atmospheric steam relief valve automatic controls in Modes 1 and 2.

In addition, an editorial change, to revise the word "with" to "within", is proposed for the ACTION statements for TS 3.7.1.6. The proposed change is shown below:

a.

With one less than the required atmospheric steam relief valves OPERABLE, restore the required atmospheric steam relief valves to OPERABLE status within 7 days; or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and place the required RCS/RHR loops in operation for decay heat removal.

b.

With two less than the required atmospheric relief valves OPERABLE, restore at least three atmospheric relief valves 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 be in at least HOT STANDBY within' the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and place the required RCS/RHR loops in operation for decay heat removal.

NOC-AE-04001 769 Attachment I Page 2 3.0

Background

System Description The main steam line from each of the four steam generators has an atmospheric steam relief valve. The valves are ASME Class 2 and are supplied with Class 1E power. These valves are required for decay heat removal and safe cooldown in accordance with Branch Technical Position RSB 5-1. In the safety analyses, operation of the atmospheric steam relief valves is assumed in accident analyses for mitigation of small break LOCA, feedwater line break, loss of normal feedwater and loss-of-offsite power.

The atmospheric steam relief valve manual controls must be OPERABLE in Modes 1, 2, 3, and 4 (Mode 4 when steam generators are being used for decay heat removal) to allow operator action needed for decay heat removal and safe cooldown in accordance with Branch Technical Position RSB 5-1.

The atmospheric steam relief valve automatic controls must be OPERABLE with a nominal set point of 1225 psig in Modes I and 2 because the safety analysis assumes automatic operation of the atmospheric steam relief valves with a nominal setpoint of 1225 psig with uncertainties for mitigation of the small break LOCA.

A pressure transmitter and pressure controller are provided for each of the steam generators to actuate the atmospheric steam relief valve and control the steam pressure at a predetermined setting. Manual control capability is provided both in the control room and on the alternate shutdown station for atmospheric steam relief valve control. The status of the atmospheric steam relief valves is indicated by the valve open/closed indicating lights and analog position indication on the valve control stations. The steam generator atmospheric steam relief valves are controlled using the Qualified Data Processing System.

The atmospheric steam relief valve controls are designed to meet those portions of Institute of Electrical and Electronics Engineers (IEEE) 279-1971 applicable to automatic and manual controls. The atmospheric steam relief valves are electro-hydraulically operated, requiring 480 VAC, 3-phase power for the hydraulic pumps and 125 VDC for the manual and automatic control portion. The control circuits are designed so that any single failure will not prevent proper system response when required. This is accomplished by redundant steam generators with an atmospheric steam relief valve available on each steam generator, any two of which are sufficient for heat removal. Two atmospheric steam relief valves are powered from independent Class lE 480 VAC, 3-phase busses with the other two atmospheric steam relief valves powered from a third independent Class I E 480 VAC, 3-phase bus. The control circuits are powered from four independent Class lE 125 VDC busses. In order to prevent interaction between redundant systems, the control channels are wired independently and are separated, with no electrical connections between control channels.

NOC-AE-04001769 Attachment I Page 3 The atmospheric steam relief valves and their controls are described in Sections 7.4.1.2 and 10.3.2.4 of the Updated Final Safety Analysis Report.

Historical Background In Reference 1, STPNOC proposed an amendment to the TS to add TS 3.3.5.1 for atmospheric steam relief valve instrumentation to ensure that the automatic feature of the atmospheric steam relief valves remain operable during Modes 1 and 2. This allowed mitigation of the consequences of the small break loss of coolant accident and meets the requirements of 10 CFR 50.46.

The requirement for manual controls for atmospheric steam relief valves to be operable for Modes 1 through 4 was moved from TS 3.7.1.6 to the new instrumentation TS 3.3.5.1.

TS 3.7.1.6 was revised to delete manual controls as a limiting condition for operation for the atmospheric steam relief valves. The limiting condition for manual controls was moved to the new instrumentation TS. Surveillance Requirement (SR) 4.7.1.6 was revised to reflect that valve operation must be verified using both automatic and manual controls following any cold shutdown of 30 days or longer or following any refueling shutdown. The wording "any cold shutdown of 30 days or longer following any refueling shutdown" was rearranged to clarify that SR 4.7.1.6 should be performed following any refueling shutdown regardless of duration.

These changes were approved by Operating License Amendment No. 114 for Unit 1 and Amendment No. 102 for Unit 2. (Reference 2)

Condition that the proposed amendment is intended to resolve The purpose of this TS is to alleviate the entry into a TS action statement for a condition not required by the safety analysis.

TS 3.3.5.1 establishes the mode applicability requirements for atmospheric steam relief valve instrumentation. As shown in Table 3.3-14, the automatic actuation control channels are only required to be operable in modes 1 and 2.

TS 3.7.1.6 establishes the requirements for the atmospheric steam relief valves separate from the instrumentation control requirements. The valves are required to be operable in modes 1 - 4. The purpose of SR 4.7.1.6 is to exercise the valves prior to startup from a cold shutdown of 30 days or longer or following any refueling shutdown to ensure that they will fully open and close. The surveillance requires that the verification be conducted using both manual and automatic controls. The purpose of SR 4.7.1.6 was not to establish mode applicability requirements for the valve controls. Instead it was to verify movement operability of the valve itself. Mode applicability for valve controls is established by TS 3.3.5.1.

TS 4.0.1 states that surveillance requirements must be met during the operational modes or other conditions specified for individual Limiting Conditions for Operation unless

NOC-AE-04001769 Attachment I Page 4 otherwise stated in an individual surveillance requirement. Failure to meet a surveillance requirement, whether such a failure is experienced during the performance of the surveillance or between performances of the surveillance, shall be failure to meet the Limiting Condition for Operation.

With the current SR 4.7.1.6, the Limiting Condition for Operation of Technical Specification 3.7.1.6 would not be met if the automatic actuation control channel of an atmospheric steam relief valve failed in Modes 3 or 4, and after valve operation had been verified by operation of automatic controls prior to startup. Since automatic controls are not required until Modes 1 and 2, entering an action statement for this condition is not needed to meet the safety analysis and is inconsistent with the requirements of TS 3.3.5.1.

Adding the proposed note to SR 4.7.1.6 clarifies that the surveillance requirement for the automatic controls of the atmospheric steam relief valve is only applicable in Modes 1 and 2. This is consistent with the requirements of TS 4.0.1 and instrumentation TS 3.3.5.1.

The second proposed change is an editorial change.

4.0 Technical Evaluation The atmospheric steam relief valve automatic controls must be operable in Modes 1 and 2 because the safety analysis assumes automatic operation of the atmospheric steam relief valves for mitigation of the small break LOCA. The atmospheric steam relief valve automatic controls are not required to be operable in Modes 3 and 4.

The proposed change to the surveillance requirement clarifies that the surveillance requirement for the automatic controls of the atmospheric steam relief valve is only applicable in Modes I and 2. This is consistent with instrumentation TS 3.3.5.1 where the mode applicability of instrumentation controls is established (Reference 2). TS 4.0.1 allows for statements in an individual SR to define when operational modes must met for specific conditions.

5.0 Regulatory Evaluation Determination of No Significant Hazards:

STPNOC has reviewed the proposed amendment request and determined that its adoption does not involve a significant hazards consideration, as discussed below.

1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No.

NOC-AE-04001769 Page 5 The proposed change does not involve a significant increase in the probability or consequences of a previously evaluated accident. The first proposed change only clarifies when SR 4.7.1.6 for the automatic controls of the atmospheric steam relief valve is applicable. The applicability is already established in TS 3.3.5.1 and meets the safety analysis. The second proposed change is editorial.

2. Does the proposed change create the possibility of a new or different accident from any accident previously evaluated?

Response: No.

The first proposed change does not create the possibility of a new or different accident from any previously evaluated. The proposed change only clarifies when SR 4.7.1.6 for the automatic controls of the atmospheric steam relief valve is applicable.

The applicability is already established in TS 3.3.5.1 and meets the safety analysis.

The second proposed change is editorial.

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No.

The first proposed change does not involve a significant reduction in the margin of safety. The proposed change only clarifies when SR 4.7.1.6 for the automatic controls of the atmospheric steam relief valve is applicable. The applicability is already established in TS 3.3.5.1 and meets the safety analysis. The second proposed change is editorial.

Applicable Regulatory Criteria:

The proposed change to the STPNOC TS will ensure that the requirements regarding mode applicability of the automatic controls of the atmospheric steam relief valves are consistent throughout the TS. The mode applicability is consistent with the STPNOC safety analysis. Automatic controls are required in Modes 1 and 2 to meet the requirements of 10 CFR 50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors."

In conclusion, based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the approval of the proposed change wvill not be inimical to the common defense and security or to the health and safety of the public.

6.0 Environmental Evaluation STPNOC has evaluated the proposed changes and determined the changes do not involve (I) a significant hazards consideration, (2) a significant change in the types or significant

NOC-AE-04001769 Attachment I Page 6 increase in the amounts of any effluents that may be released offsite, or (3) a significant increase in the individual or cumulative occupational exposure. Accordingly, the proposed changes meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9), and an environmental assessment of the proposed changes is not required.

7.0

References:

1. Letter from T.H. Cloninger, STPNOC to the NRC Document Control Desk, dated March 22, 1999, "Proposed New Amendment for Atmospheric Steam Relief Valve Instrumentation and Revised Amendment of Technical Specification 3.7.1.6, Atmospheric Steam Relief Valves" (NOC-AE-000462)
2. Letter from Thomas W. Alexion, NRC to Mr. William T. Cottle, STPNOC, dated August 19, 1999, "South Texas Project, Units 1 and 2-Issuance of Amendments Re:

Atmospheric Steam Relief Valves (TAC Nos. MA5078 and MA5079)"

NOC-AE-04001769 Annotated Technical Specification Page

NOC-AE-04001769 Page I PLANT SYSTEMS ATMOSPHERIC STEAM RELIEF VALVES LIMITING CONDITION FOR OPERATION 3.7.1.6 At least four atmospheric steam relief valves shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, 3, and 4.*

ACTION:

a.

With one less than the required atmospheric steam relief valves OPERABLE, restore the required atmospheric steam relief valves to OPERABLE status within 7 days; or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and place I the required RCS/RHR loops in operation for decay heat removal.

b.

With two less than the required atmospheric relief valves OPERABLE, restore at least three atmospheric relief valves 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 be in at least HOT STANDBY withii the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and place the required RCS/RHR loops in operation for decay heat removal.

SURVEILLANKCE REQUIREMENTS 4.7.1.6 Each atmospheric relief valve shall be demonstrated OPERABLE prior to startup following any COLD SHUTDOWN of 30 days or longer or following any refueling shutdown, by verifying that all valves will open and close fully by operation of automatics and manual controls.

I

.Reaulreddto b-e mt for automatic coiite6ls'onlVln MODES Ijnd 2 I

SOUTH TEXAS - UNITS 1 & 2 3/4 7-10 Unit 1 -Amendment No. 444 Unit 2 -Amendment No. 402

NOC-AE-04001769 Revised Technical Specification Page

PLANT SYSTEMS ATMOSPHERIC STEAM RELIEF VALVES LIMITING CONDITION FOR OPERATION 3.7.1.6 At least four atmospheric steam relief valves shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, 3, and 4.*

ACTION:

a.

With one less than the required atmospheric steam relief valves OPERABLE, restore the required atmospheric steam relief valves to OPERABLE status within 7 days; or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and place I the required RCS/RHR loops in operation for decay heat removal.

b.

With two less than the required atmospheric relief valves OPERABLE, restore at least three atmospheric relief valves 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 be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and place the required RCS/RHR loops in operation for decay heat removal.

I SURVEILLANCE REQUIREMENTS 4.7.1.6 Each atmospheric relief valve shall be demonstrated OPERABLE prior to startup following any COLD SHUTDOWN of 30 days or longer or following any refueling shutdown, by verifying that all valves I will open and close fully by operation of automatic# and manual controls.

I

" Required to be met for automatic controls only in MODES I and 2.

I SOUTH TEXAS - UNITS I & 2 3/4 7-10 Unit 1 - Amendment No. 114 Unit 2 - Amendment No. 402

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