ML20214L293
| ML20214L293 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee  |
| Issue date: | 08/26/1986 |
| From: | Murphy W VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20214L296 | List: |
| References | |
| FVY-86-80, NUDOCS 8609100060 | |
| Download: ML20214L293 (8) | |
Text
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VERMONT YANKEE NUCLEAR POWER CORPORATION
. RD 5, Box 169, Ferry Road, Brattleboro, VT 05301 neptv ro: l g ENGINEERING OFFICE 1671 WORCESTER ROAD
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- FRAMINGHAM, MASSACHUSETTS 01701
- August 26, 1986 mtesons sir-arr eioo FVY 86-80 United States Nuclear Regulatory Commission Washington, DC 20555 Attention: Office of Nuclear Reactor Regulation Mr. Harold R. Denton
References:
(a) License No. DPR-28 (Docket No. 50-271)
(b) Letter, VYNPC to USNRC, FVY 83-1, dated January 10, 1983 Proposed Change 103 (c) Letter, USNRC to VYNPC, NVY 83-66, dated March 28, 1983, Amendment No. 76
Subject:
Changes To Technical Specifications To Reflect Analog Equipment Replacement and Administrative Changes
Dear Sir:
Pursuant to Section 50.59 of the Commission's Rules and Regulations, Vermont Yankee Nuclear Power Corporation hereby proposes the following modification to Appendix A of the operating license:
Proposed Cnange This proposed change involves deletion and insertion of pages in the Vermont Yankee Technical Specifications as listed in Attachment 1. The changes to the Technical Specifications being proposed are outlined below:
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- 1. Pages 35, 36, 37, 50, and 51 are being revised to provide actual instrument numbers rather than an undefined number, and make the l trip setting the same for common instruments which provide inputs to l different systems.
- 2. Pages 50 and 51 provide revised calibration requirements for the Reactor Vessel Shroud instrumentation input to the Emergency Core cooling Systems to reflect the replacement of level and pressure switches with analog loops.
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United States Nuclear Regulatory Commission August 26, 1986 Attention: Mr. Harold R. Denton Page 2
- 3. Pages 50, 51, 52, 55, 56, 57, and 59 delete the reference to Note 2 from the Trip System logic tests for portions of the Emergency Core Cooling Systems, High Pressure Injection System. Reactor Core Isolation Cooling System, Reactor Building Ventilation and Standby Cas Treatment System, and control rod block instrumentation.
- 4. Pages 127 and 139a revise the Limiting condition for operation and Bases (respectively) for operation with one of the Pressure Suppression Chamber - Reactor Building Vacuum Breaker Systems out of service.
Reason for Change changes to the Technical Specifications are proposed for the following reasons:
- 1. The numbers used in Tables 3.2.1 and 4.2.1 to differentiate between instruments are undefined and in some cases misleading. These numbers are being replaced by the actual instrument numbers, and where a common instrument provides an input into different systems, the trip level setting is changed so that both are the same. These changes are proposed to reflect the replacement of level and pressure switches with analog loops. This upgrade is expected to increase plant reliability, reduce setpoint drift, and improve overall plant safety.
- 2. Changes to the surveillance and calibration requirements in Table 4.2.1 reflect the replacement of level and pressure switches with analog instrumentation.
- 3. In an effort to improve and simplify the Technical Specifications, the reference to Note 2 is being deleted from tables where this note is not applicable.
- 4. Based upon review of an event involving a failure of one of the Pressure Suppression Chamber-Reactor Building Vacuum Breaker Systems, revision is being made to the Technical Specifications to better reflect the intent of the requirements.
Basis for Change The proposed changes to the Technical Specifications are based on the following:
- 1. Instruments which are used in more than one system are labeled differently in the Technical Specification tables depending upon the system. The existing labels are being deleted and the actual tag numbers are being added to identify the instruments to improve clarity. Common instruments provido low reactor pressure permissive signals to the Core Spray and Low Pressure Coolant Injection Systems. Since the basis for the setpoint is the same for both
United States Nuclear Regulatory Commission August 26, 1986 Attention: Mr. Harold R. Denton Page 3 systems, the setpoints listed for core spray are being changed to be the same as those given for the Low Pressure Coolant Injection System.
- 2. The surveillance and calibration requirements have been modified to agree with those which have previously been approved for similar analog instrumentation utilized at Vermont Yankee (Reference (c)).
Replacenent of the level and pressure switches with more reliable instrumentation improves plant reliability while, at the same time, does not change the design basis, protective function, redundancy, trip point, or logic of the original system.
- 3. Note 2 to Tables 4.2.1 through 4.2.6 of the Technical Specifications states, "During each refueling outage, simulated automatic actuation which opens all pilot valves shall be performed such that each trip system logic can be verified independent of its redundant counte rpart. " This note only applies to the Automatic Depressurization System and the primary containment isolation instrumentation, these being the only systems having pilot valves.
In an effort to improve the quality and eliminate confusion in the Technical Specifications, the reference to this note is being removed from tables where it is not applicable.
- 4. Section 3.7.A.5.b is being revised to better reflect the intent of the requirements to preserve both the containment isolation and vacuum relief functions of the Pressure Suppression Chamber -
Reactor Building Vacuum Breaker Systems. The proposed wording removes the existing requirement to lock the valve closed since this is inconsistent with the other containment isolation requirements (Section 3.7.D) and defeats the vacuum breaker function of the system. Also it maintains the time limit on operation in this mode since it is not desirable to operate in this condition for an extended period of time. The basis for Section 3.7.A is revised to better reflect this change.
Safety Evaluation The changes proposed by this amendment request do not present any unreviewed safety questions as defined in 10CFR50.59. The changes proposed reflect the installation of analog instrumentation and provide certain clarifications to the Technical Specifications. Vermont Yankee has evaluated each of the proposed changes and determined that:
- 1. There is no increase in the probability of occurrence or the consequences of an accident or malfunction of equipment important to safety previously evaluated in the safety analysis report.
- 2. The possibility for an accident or malfunction of a different type than any evaluated previously in the safety analysis report is not created.
United States Nuclear Regulatory Commission August 26, 1986 Attention: Mr. Harold R. Denton Page 4
- 3. No margins of safety as defined in the basis for the Technical Specifications are reduced.
This proposed change was reviewed by the Vermont Yankee Nuclear Safety Audit and Review Committee.
Significant Hazards Consideration, The standards used to arrive at a determination that a request for amendment involves no significant hazards consideration are included in the Commission's regulations, 10CFR50.92, which state that the operation of the facility in accordance with the proposed amendment would not: (1) involve a significant increase in the probability or consequences of an accident previously evaluated, (2) create the possibility of a new or different kind of accident from any accident previously evaluated, or (3) involve a significant reduction in a margin of safety.
The discussion below addresses each of the proposed changes with respect to these three criteria and demonstrates that the proposed amendment involves a no-significant hazards consideration.
- 1. The proposed changes to Pages 35, 36, 37, 50, and 51 revise Tables 3.2.1 and 4.2.1 to provide instrument tag numbers which will improve the clarity of the Technical Specifications. The revisions to the trip level setpoints listed in Table 3.2.1 of the Technical Specifications also reflect the replacement of level and pressure switches with analog instruments. This change improves the consistency of the Technical Specifications for instruments common to more than one system. Replacement of switches with more reliable instrumentation improves plant reliability and does not change the design basis, protective function, redundancy, or logic of the original system. As such, this change does not impact the probability or consequences of any accident previously evaluated, nor does it create the possibility of a new or different kind of accident from any accident previously considered. Further, no change in any plant safety margin is required for the reasons stated above.
- 2. The proposed changes to pages 50 and 51 revise the surveillance and calibration requirements in Table 4.2.1 to reflect the replacement of level and pressure switches with analog instrumentation. These l modified requirements are consistent with those previously approved for similar analog instrumentation utilized at Vermont Yankee (Reference (c)). The previous requirement of once every three months was appropriate for level and pressure switches. The revised requirement of once every operating cycle is appropriate for the now analog loops because of the reduced setpoint drift. As such, there is no impact in the probability or consequences of accident previously evaluated by this change sinco it does not involve safety system or primary system boundaries. Similarly, no new kinds of i
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United States Nuclear Regulatory Commission August 26, 1986 Attention: Mr. Harold R. Denton Page 5 accidents involving safety-related systems are created by this change, nor are any changes required in plant operating or design safety margins.
- 3. The proposed changes to Pages 50, 51, 52, 55, 56, 57, and 59 delete a reference to Note 2 in Tables 4.2.1 through 4.2.6. in order to improve and simplify the Technical Specifications. Because the note only applies to those systems which have pilot valves, reference to it is being deleted from those systems for which it is not applicable. The deletion of an inapplicable reference to a table notation has no bearing on any accident previously evaluated, nor does it create the possibility of a new or different kind of accident. Similarly, no changes in any plant operating or design bases safety margins are required by the deletion.
- 4. The proposed changes to Pages 127 and 139a Revise Section 3.7.A.S.b of the Technical Specifications to better reflect the intent of the requirements. The change on page 127 is made to the' Limiting Conditions for Operation (LCO) of the pressure suppression Chamber-Reactor Building vacuum breakers. The previous LCO required locking the vacuum breaker closed if it was inoperable. The revised LCO specifies that a valve in the failed line must be verified to be in the isolated condition allowing greater flexibility in meeting the intent of the Technical Specification requirements. The new requirement meets the intent to isolate the failed vacuum breaker and also improves consistency between LCOs in the Technical Specifications. The change to Page 139a revises the basis for this section to better reflect the intent associated the new LCO requirement which is now more consistent with other containment isolation requirements. Because these changes provide greater flexibility in meeting an existing requirement and improve consistency with other containment isolation requirements in the Technical Specifications, the probability or consequences of any accident previously evaluated is not nignificantly increased.
Additionally, the possibility of a new or different kind of accident from any accident previously evaluated is not created and no significant reduction is an margin of safety is involved.
Therefore, we conclude that these proposed changes do not constitute a significant hazards consideration, as defined in 10CFR50.92(c).
i Fee Determination In accordance with the provisions of 10CFR170.12, an appilcation fee of
$150.00 is enclosed.
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s United States Nuclear Regulatory Commission August 26, 1986 Attention: Mr. Harold R. Denton Page 6 Schedule of Channe This change will be incorporated into the Vermont Yankee Technical Specifications as soon as practicable following receipt of your approval.
We trust that the information provided above adequately supports your requent, however, should you have any questions in this matter, please contact us.
Very truly yours.
VERMONT YANKEE NUCLEAR POWER CORPORATION Warren P. rphy Vice President and anager of Operations WPM /no Enclosures cc: U.S. Nuclear Regulatory Commission Document Control Desk (40 copies)
Vermont Department of Public Services 120 State Street Montpelier, Vermont 05602 Attention: Mr. C. Tarrant, Chairman STATE OF VERMONT )
)ss OF WINDHAM COUNTY)
Then personally appeared before me. Warren P. Murphy, who, being duly sworn, did state that he is Vice President and Manager of Operations of Vermont Yankee Nuclear Power Corporation, that he is duly authorized to execute and file the foregoing document in the name and on the behalf of Vermont Yankee Nucicar Power Corporation and that the statements therein are true to the best of his knowledge and belief, h [
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'i Notary Public My Commission Expires 1 i Document %Nos.
1302c Y 0349s 0348s g 'opt u6,
ATTACHMENT 1 Pages Deleted Pages Inserted 35 35 36 36 37 37 50 50 51 51 52 52 55 55 56 56 57 57 59 59 127 127 139a 139a
United States Nuclear Regulatory Commission- August 15, 1986 Attention: Mr. Harold R. Denton Page 7 ATTACHMENT 1 Pages Deleted Pages Inserted 35 35 36 36 37 37 50 50 51 51 52 52 55 55
' 56 56 57 57 i 59 59 127 127 139a 139a 1
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