ML20137S640
| ML20137S640 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 04/10/1997 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20137S637 | List: |
| References | |
| NUDOCS 9704150201 | |
| Download: ML20137S640 (4) | |
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i UNITED STATES f
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~ NUCLEAR REGULATORY COMMISSION y
o WASHINCTON. D.C. 20666-0001 i
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i SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 136 TO FACILITY OPERATING LICENSE NO. NPF-49 NORTHEAST NUCLEAR ENERGY COMPANY. ET AL.
MILLSTONE NUCLEAR POWER STATION. UNIT NO. 3 DOCKET NO. 50-423
1.0 INTRODUCTION
t By letter dated June 20, 1995, as supplemented August 30, 1995, the Northeast i
Nuclear Energy Company (the licensee), submitted a request for changes to the Millstone Nuclear Power Station, Unit No. 3 Technical Specifications (TS).
Also, by letter dated January 17, 1996, the licensee requested that a condition be deleted from the Millstone 3 operating license. The requested changes to the TS would relocate the applicable requirements for main steam L
line isolation valves (MSIVs) from Specification 3.6.3 " Containment Isolation Valves" to Specification 3.7.1.5 " Main Steam Line Isolation Valves."
In addition, Specification 3.7.1.5 would be revised to incorporate some of the guidance of the Improved Standard Technical Specifications for Westinghouse plants (NUREG-1431). The August 30, 1995, letter provided clarifying information that did not change the scope of the June 20, 1995, application and the initial proposed no significant hazards consideration determination.
The January 17, 1996, amendment request would delete a license requirement to submit responses to and to implement requirements of Generic Letter 83-28, because the requirement has been completed. Generic Letter 83-28 pertains to the Salem anticipated transient without scram (ATWS) event.
2.0 EVALUATION 2.1 Section 3.6.3 " Containment Isolation Valves" This specification states that containment isolation valves sha!1 be operable with isolation times less than or equal to the required isolation times.
Specification 3.6.3.a states that with one or more of the isolation valve (s) inoperable, maintain at least one isolation valve operable in each affected penetration that is open and restore the inoperable valve (s) to operable status within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. The current TS would include the MSIVs since these valves serve as containment isolation valves. However, because of the Millstone Unit 3 main steam system design, it is not possible for the licensee to comply with this requirement since there is only one containment isolation valve in each main steam line.
The Improved Standard Technical Specifications for Westinghouse designed plants (NUREG-1431) addresses this problem by specifying that the TS action statements only address penetration flow paths with two containment isolation 9704150201 970410 PDR ADOCK 05000423 P
valves. NUREG-1431 also specifies separate action statements for MSIVs. The licensee proposes to add the following note to the Specification.
The provisions of this Specification are not applicable for main steam line isolation valves. However, provisions of Specification 3.7.1.5 are applicable for main steam line isolation valves.
Since the applicable requirements for MSIVs are covered by TS 3.7.1.5, the staff finds the note acceptable.
In addition, Specification 3.6.3 requires that an inoperable MSIV be restored to operable status within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. As discussed below, the licensee is proposing an allowed outage time (A0T) of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> for the MSIVs, which is consistent with NUREG-1431.
Finally, removal of MSIVs from the containment isolation valve specification does not affect leak testing of the valves since these valves are not Type C leak tested in accordance with 10 CFR Part 50, Appendix J.
Therefore, the staff finds that relocating the applicable requirements for MSIVs to TS 3.7.1.5 acceptable and consistent with NUREG-1431.
2.2 Specification 3.7.1.5 " Main Steam Line Isolation Valves" The licensee has proposed making several changes that are consistent with the Improved Standard Technical Specifications for Westinghouse-designed plants (NUREG-1431).
i Specification 3.7.1.5 has been revised to state that the Limiting Condition for Operation (LCO) is applicable for MODE I and for MODES 2, 3, and 4 except i
when the MSIVs are closed and deactivated. This is consistent with NUREG-1431 and is acceptable because when the MSIVs are closed, they are performing their safety function.
If they are deactivated, they cannot open, either from an inadvertent command or spuriously. This requirement is consistent with Action Statement b. of LCO 3.6.3, which requires that, with an isolation valve inoperable, the affected penetration shall be isolated by the use of at least one deactivated automatic valve secured in the isolation position.
The allowed outage time of Specification 3.7.1.5 has also been revised.
In MODE 1, power operation may continue for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> with one MSIV inoperable.
In MODES 2 3, and 4, operation may continue for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> with one or more MSIVs inoperaole.
Eight hours is consistent with NUREG-1431 for MSIVs but it is 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> loager than the allowed outage time for other containment isolation valves. The staff considers this to be acceptable based on the low probability of an accident occurring during this time, which will require MSIV closure. Also, since MSIVs are GDC-57 valves, that is, they isolate a closed system, which is neither connected directly to the reactor coolant pressure i
boundary nor to the containment atmosphere, a longer A0T is acceptable.
l The licensee also proposes to verify that the MSIV is closed once every 7 days.
This is consistent with NUREG-1431 and is a reasonable time interval since the positions of the MSIVs are indicated in the control room, and other administrative controls are in effect to ensure the valves are in the closed position.
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i In MODES 2,.3 and 4, the licensee proposes a separate entry condition for each inoperable MSIV. This is consistent with NUREG-1431 and is reasonable since i
-the MSIV is performing its safety function in the closed position.
The licensee also proposes to modify the surveillance requirements 4.7.1.5.1 and 4.7.1.5.2, which raquire that full closure be verified to be within 10 seconds (in MODES 1, 2 and 3) or 120 seconds (in MODE 4) by adding the words "on an actual or simulated actuation signal." This is consistent with NUREG-1431 and is acceptable. The licensee's August 30, 1995, submittal modified the-proposed Bases accompanying the_ proposed TS changes to identify the l
specific simulated actuation signals.
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A simulated signal is defined as any of the following engineered safety features actuation system instrumentation functional units per Technical i
Specification Table 4.3-2: 4.a.1) manual initiation, individual, 4.a.2) manual initiation, system, 4.c. containment pressure high-2, 4.d. steam line pressure low, and 4.e. steam line pressure - negative rate high.
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2.3 Generic Letter 83-28 reauirements j
On July 8, 1983, the staff issued Generic Letter (GL) 83-28 in response to the Salem ATWS event. The GL identified the actions that the staff believed were necessary to respond to the ATWS event, and requested that the licensees i
furnish "the status of current conformance with the positions contained
[within the GL], and plans and schedules for any needed improvements for conformance with the positions." Millstone 3 responded to GL 83-28 in a number of submittals, and the NRC staff concluded that the responses were acceptable. By letter dated January 17, 1996, the licensee summarized the Millstone 3 responses to GL 83-28 and the staff documents approving the j
licensee's responses. The licensee's proposal to delete License Condition 2.C.(4) from the license is purely administrative, because the staff has approved, by various separate documents, the acceptability of all the t
requirements of GL 83-28.
Because the license requirement has been met and is no longer necessary, this change is acceptable.
2.4 Bases Chanaes By letters dated June 20, 1995, February 5, 1996,.and March 21 and 26, 1997,
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the licensee submitted Bases changes, which affect Section B 3/4.7 of the TS.
These changes are outlined below:
j (1) By letter dated June 20, 1995, the licensee submitted the Bases change associated with the MSIV surveillance changes, which are discussed in Section 2.2 of this safety evaluation.
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(2) By letter dated February 5, 1996, the licensee requested a TS change concerning inservice testing.
Included with this request was a Bases change associated with the control room emergency ventilation system and
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the control room envelope pressurization system.
_ (3) By. letter da.ted March 21, 1997, the licensee provided changes to the Bases associated with potential variations in the temperature averaging methodology for determining the Millstone Unit 3 ultimate heat sink temperature.
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(4) By letter dated March 26, 1997. the licensee provided additional changes to the Bases associated with the control room emergency ventilation system and the control room envelope pressurization system.
Since all four of these Bases changes affect Section B 3/4.7 of the TS, the NRC staff is issuing them in a group to avoid errors in revising the TS. The staff has reviewed the proposed changes and has no objection to the proposed wording.
3.0 STATE CONSULTATION
In accordance with the Comission's regulations, the Connecticut State official was notified of the proposed issuance of the amendment.
The State official had no coments.
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 and changes surveillance requirements.
The NRC staff has determined that the amendment 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 previously issued proposed findings that the amendment involves no significant hazards consideration, and there has been no public comment on such findings (60 FR 39445 and 61 FR 7555). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 1
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, 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 j
activities will be conducted in compliance with the Commission's regulations, i
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 Contributors:
R. Lobel V. Rooney Date: April 10, 1997 i