ML20083P944
| ML20083P944 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 05/18/1995 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20083P580 | List: |
| References | |
| NUDOCS 9505250043 | |
| Download: ML20083P944 (4) | |
Text
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- 4 UNITED STATES j
j NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 2006M001
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SAFETY EVALUATION BY THE OFFICE OF NVCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.189 TO FACILITY OPERATING LICENSE NO. DPR-65 NORTHEAST NUCLEAR ENERGY COMPANY THE CONNECTICUT LIGHT AND POWER COMPANY THE WESTERN MASSACHUSETTS ELECTRIC COMPANY MILLSTONE NUCLEAR POWER STATION. UNIT NO. 2 DOCKET NO. 50-336
1.0 INTRODUCTION
By letter dated April 21, 1995, the Northeast Nuclear Energy Company (the licensee) submitted a request for changes to the Millstone Nuclear Power Station, Unit No. 2 Technical Specifications (TSs). The requested changes would would revise TS 3.1.2.4, " Charging Pumps-0perating,"by adding a note that indicates that the provisions of TS 3.0.4 and 4.0.4 are not applicable for entry into MODE 4 from MODE 5.
2.0 BACKGROUND
AND DISCUSSION Amendment 185 issued by NRC letter of February 15, 1995, modified TS 3.1.2.3,
" Charging Pump-Shutdown," to indicate that with relief capability provided by the power-operated relief valves (PORVs), only one charging pump and one high-pressure safety injection (HPSI) pump would be operable in MODES 5 and 6.
This change was made to address Low Temperature Overpressure Protection (LTOP) issues. The TS was further modified to allow an additional charging pump and an additional HPSI pump to operate provided the reactor coolant system (RCS) was vented through a passive vent of greater than or equal to 2.8 in'.
This modification was made to address shutdown risk management and LTOP issues.
When entering MODE 4 from MODE 5, Millstone Unit 2 is unable to maintain a passive vent of greater than or equal to 2.8 in'.
Therefore, TS 3.1.2.3 limits Millstone Unit 2 to only one charging pump and one HPSI pump for MODES 5 and 6.
TS 3.1.2.4, " Charging Pumps-0perating," requires two charging pumps be operable in HODES 1, 2, 3, and 4.
The ACTION statement requires that if only one charging pump is operable that an additional charging pump must be restored to i
an operable status or the unit must be shut down.
TS 3.0.4 prohibits entrance into an operational MODE when the limiting condition for operation (LCO) is not met and the ACTION statement requires a shutdown.
Similarly, TS 4.0.4 prohibits entry into an operational MODE if the Surveillance Requirement cannot be met.
9505250043 950518 PDR ADOCK 05000336 P
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O 'Therefore the TS as currently written prohibits entrance into MODE 4 due to plant limitations on the restoration of two charging pumps prior to entry into MODE 4.
Thus the licensee has proposed to add a footnote to TS 3.1.2.4 which indicates that an exception to TSs 3.0.4 and 4.0.4 is provided for entry into MODE 4 from MODE 5 for no greater than 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> or prior to entry into MODE 3, whichever occurs first.
The proposed change would also modify the accompanying bases by clarifying that in MODES 5 and 6 only one charging pump and only one HPSI pump may be operable with relief provided by the power operated relief valves.
In addition, a discussion has been added which describes why Technical Specification.3.1.2.4 has taken an exception to Technical Specifications 3.0.4 and 4.0.4.
The proposed change has been requested on an exigent basis to permit the licensee to permit Millstone Unit 2 to proceed in startup from MODE 5 to MODE 4 without unnecessary delay.
3.0 EVALUATION TS 3.1.2.3 requires that one charging pump and one HPSI pump be operable in MODES 5 and 6.
The specification allows an additional charging pump and HPSI pump to be operable provided the RCS has a passive vent of greater than or equal to 2.8 square inches.
TS 3.1.2.4 requires that at least two charging pumps are operable in MODES 1, 2, 3, and 4, except when the RCS is less than 300*F, then a maximum of two charging pumps can be operable.
Entry into MODE 4 from MODE 5 requires that two charging pumps be operable.
In MODE 5, only one charging pump may be operable.
The proposed TS modification will' allow the entrance into MODE 4 and the subsequent testing of the second charging pump.
The testing of the pump is required prior to declaring the pump operable.
TSs 3.0.4 and 4.0.4 prohibit entry into an operational mode when the LCOs are not met and the assuciated action statement requires a shutdown if they are not met within a specified time interval or if the surveillance has not been performed.
Currently, the TSs would prohibit entrance into MODE 4 from MODE 5 due to the inability to provide two operable charging pumps at the start of MODE 4.
Thus a situation exists with a requirement that will not support plant operation without relief.
We have reviewed the licensee's proposed change and have determined it to be acceptable. The proposed change will allow mode change from MODE 5 to MODE 4 and continued operation. The small delay in returning a second charging pump to operable status in MODE 4 will not detrimentally impact the risks associated with shutdown management practices, j
.- 4.0 W ENT CIRCUMSTANCES Pursuant to 10 CFR 50.91(a)(6), the licennee requested the proposed amendment on an exigent basis. The proposed change would parmit Millstone Unit 2 to proceed in startup from MODE 5 to MDE 4 witheat unnecessary delay.
The condition that lead to discovery of need was a result of recent operator training involving Amendment No. 185 which was issued on February 15, 1995.
Notice of the staff's proposed determination that this proposed amendment involves no signif'icant hazards consideration was published in the Federal Reaister on May 2, 1995 (60 FR 21558). The Commission has made a final determination that the proposed amendment does not involve a significant hazards consideration as discussed in Section 5.0.
5.0 FINAL NO SIGNIFICANT HAZARDS CONSIDERATION
DETERMINATIQH The Comission has made a final determination that the amendment involves no significant hazards consideration. Under the Comission's regulations in 10 CFR 50.92(c). this means that the operation of the facility in accordance with the prososed amendment would not (1) Involve a significant increase in the pro) ability or consequences of an accident previously evaluated; or (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, i
The Commission has evaluated the proposed changes against the above standards as required by 10 CFR 50.91(a) and has concluded that the changes do not:
1.
Involve a significant increase in the probability or consequences of an accident previously evaluated.
The proposed TS change will require that a second charging pump be l
returned to service within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of. entering MODE 4 or prior to entering MODE 3, whichever occurs first. The addition of the footnote indicating that T$s 3.0.4 and 4.0.4 are not applicable for entry into MODE 4 from MODE 5 will allow for the testing and subsequent return to service of a charging pump that was required to be inoperable in MODE 5.
The testing is necessary to restore the pump to operable status $ en the reactor coolant system is less than 300 F.
The less than 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> delay in verifying the operability of the second charging pump after entry into MODE 4 does not significantly affect the overall risk. The TS as proposed, will allow the plant to operate. Without the proposed change a j
situation would be created in which the plant could not be permitted to make the change from MODE 5 to MODE 4 and, therefore, the plant could not continue to opwate.
The aidition of the proposed footnote to TS 3.1.2.4 will not significantly increase the probability or consequences of an accident previously evaluated. The charging systems safety related functions are not being impacted by the proposed chang.
b t,
a 2.
Create the possibility of a new or different kind of accident from any previously evaluated.
The proposed change does not alter or affect the design, function, or operation of the plant. The proposed change will allow the licensee to perform the required operability tests to support the restoration of a charging pump to an operable status for MODES 1, 2, 3, and 4.
3.
Involve a si,gnificant reduction in a margin of safety.
The proposed modification will allow for the restoration of a second charging pump to support plant operation in MODES 1, 2, 3, and 4.
Testing of the charging pump is necessary to verify operability of the pump.
Sufficient flow is provided by the remaining available pumps to address shutdown risk issues. The proposed change will not negatively impact the LTOP evaluation or boron dilution analysis.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Connecticut State official was notified of the proposed issuance of the amendment. TM State official had no comments.
4.0 ENVIRONMEN1AL 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 amen', ment 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 )reviously issued a proposed finding that the amendment involves no significant iazards consideration, and there has been no public comment on such finding (60 FR 21558).
The Commission has made a final determination that the amendment involves no significan' hazards consideration. Accordingly, the amendment meets the eligibility critu for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 UM 31.22(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, that:
(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 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: G. Vissing Date: May 18, 1995
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