ML20217Q358
| ML20217Q358 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 04/08/1998 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20217Q347 | List: |
| References | |
| GL-83-36, NUDOCS 9804100408 | |
| Download: ML20217Q358 (3) | |
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UNITED STATES NUCLEAR REGULATORY COMMISSION O
WASHINGTON, D.C. spees.0001 SAFETY EVALUATION BY THE OFFICE OF NUni FAR REACTOR REGULATION RFI ATED TO AMENrmENT NO.15 8TO FACILITY OPERATING LICENSE NO. DPR-28
. VERMONT YANKFF NUct FAR POWER CORPORATION VERMONT YANKFF NUni FAR POWER STATION
.2 DOCKET NO. 50-271
1.0 INTRODUCTION
' By letter dated August 22,1996, the Vermont Yankee Nuclear Power Corporation (the licensee) submitted a request to amend the Vermont Yankee Nuclear Power Station Technical Specifications (TSs). The proposed amendment would revise the TSs to change the action statement for the high range stack nobie gas menitor. The current TSs require a plant shutdown if Control Room indication for this monitor cannot be restored within 30 days. The licensee proposed to change the TSs to require preparation and submittal of a special report to the NRC if Control Room indication is not restored within 7 days and remove the requirement to shutdown the unit. The lice,nsee stated that the new TSs are based on the guidance of Generic Letter (GL) 83-36, NUREG-0737 Technical Specifications.
~ 2.0 EVALUATION
. Final Safety Analysis Report (FSAR) section 7.12.3 describes the plant stack radiation monitor system. The objective of the system is to sample, monitor, indicate, and record the radioactivity level of the station emuent gases being released from tne plant stack during operation and to alert operating personnel in the event radiation levels approach or exceed pre-established limits.
i Radio-gas monitor Ill (17-155) provides indication of high-range discharges of radioactive gases.
The monitor indicates and alarms in the Control Room; no control action is provided.
TS 3.g, Radioactive Emuent Monitoring Systems, contains requirements for gaseous process and emuent monitoring including alarm / trip setpoints to prevent exceeding allowable doses.
TSs 3.2, Protective Instrument Systems, requires that the post-a' cident instrumentation that e
displays information in the Control Room shall be in accordance with Table 3.2.6 during poww operation. TSs Table 3.2.6 for the stack noble gas emuent monitor, meter RM-17-155, refers to j
Note 7 which states:
l "From and after the date that this parameter is unavailable by Control Room indication,
. and cannot be restored within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, continued reactor operation is permissible for the i
next 30 days provided that local sampling capacity is available. If the Control Room indication cannot be restored within 30 days, the reactor shall be in hot shutdown within six hours and in cold shutdown within the subsequent 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />."
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9004100408 900408 1
DR ADOCK 050002 1
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.. The licensee proposed to modify Note 7 to state:
"From and after the date that this parameter is unavailable by Control Room indication,.
within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> ensure that local sampling capability is available. If the Control Room
' indication is not restored within 7 days, prepare and submit a special report to the NRC
. within 14 days following the event, outlining the action taken, the cause of the 1
inoperability, and the plans and schedule for restoring the system to operable status."
This change essentially replaces a 30-day shutdown action statement with a 14-day reporting
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requirement.
GL 83-36 Enclosure 1 provided staff guidance on TS for certain items including noble gas
- effluent monitors and states:
" Noble Gas effluent monitors provide information, during and following an accident, which are considered helpful to the operator in accessing the plant condition, it is desired that these monitors be operable at all times during plant operation, but they are not required for safe shutdown of the plant. In case of failure of the monitor, appropriate actions should be taken to restore its operational capability in a reasonable period of time. Considering the importance of the availability of the equipment and possible delays
- involved in administrative controls,7 days is considered to be the appropriate time period to, restore the operability of the monitor. An attemate method for monitoring the effluent should be initiated as soon as practical, but no later than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> after the '
identification of the failure of the monitor. If tM monitor is not restored to operable condidon within 7 days after the failure, a special report should be submitted to the NRC 1
within 14 days following the event, outlining the cause of inoperability, actions taken, and the planned schedule for restoring the system to operable status."
i The licensee stated that the high range stack noble gas monitor consists of a single instrument with no redundant counterpart. The proposed change will minimize the potential for an unnecessary shutdown in the event the instrument is damaged by lightning, or omerwise out of service and cannot be immediately restored. This monitor serves as input for dose projections i
associated with initial estimation of off-site conditions and is used prior to the acquisition of stack isotopic sample data which provides more accurate indicatien of stack activity. The licensee considered that it is not appropriate to impose stringent requirements on the operation of the unit due to the passive function of this instrument and the ability to monitor this parameter utilizing altemate methods. This monitor does not have any safety function associated with the prevention or automatic mitigation of design basis accidents, neither does it provide primary information needed to permit the Control Room operating personnel to take required manually
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controlled actions.
Since attemete means to monitor this parameter will be provided within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, and the monitor provides no control functions, the staff finds the proposed change acceptable. In addition, the proposed change conforms to the staff guidance of GL 83-36.
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3.0 STATE CONSULTATION
in accordance with the Commission's regulations, the Vermont State official was notified of the proposed issuance of the amendment. The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in 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 issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (62 FR 30647).
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 statement or environmental assessment need be prepared in connection with the issuance of the amendment.
5.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above. thatr (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 con 6Jcted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
' Principal Contributor: Richard P. Croteau Date: April 8,1998
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