ML20076A745
| ML20076A745 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 06/27/1991 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20076A743 | List: |
| References | |
| NUDOCS 9107080274 | |
| Download: ML20076A745 (5) | |
Text
- ___________
rCJ M GUk l =.
!T C i UNITED STATES
{.!W i
NUCLEAR REGULATORY COMMISSION
[
W ASHINGTON. D.C. 20565 os
%.~. >.. y SAFETY EVALUATION BY THE 0FFICE OF NUCLEAR-REACTOR REGUL ATION RELATED.TO AMENDMENT-NO.qss T0. FACILITY.0PERATING. LICENSE.NO. 0PR-53 AND. ANENDNENT -NO.195, TO FACILITY OPERATING LICENSE NO. OPR-69 BALTIMORE GAS AND ELECTRTC-COMPANY CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT N05. 1 AND.2 DOCKET NOS. 50-317 AND 318
1.0 INTRODUCTION
By letter dated November 7,1990, as supplemented May 20, 1991, Baltimore Gas and Electric Company (the licensee) submitted a request for changes to the Calvert Cliffs Nuclear Power Plant Unit Nos. I and 2, Technical Specifications (TS).
The requested changes would modify Technical Specifications (TS) action statements of TS 3.8.1.2, 3.8.2.2, 3.8.2.4, and 3.9.4 in relation to the limiting condition for operation (LCO) requirements for the A.C. electrical power sources, A.C. electrical busses, D.C. electrical equipment and busses, and the containment penetrations.
The requirement to establish containment integrity is replaced with the requirement to suspend all operations relative to:
core alterations, positive reactivity changes, the movement of irradiated fuel, and the movement of heavy loads over irradiated fuel.
The change also requires that containment penetration closure, as identified in TS 3.9.4, be established within 8-hours and corrective actions be initiated immediately to restore the minimum A.C. electrical power sources, A.C. electrical busses and D.C. electrical equipment and busses.
The requirements of TS 3.9.4 are modified to be consistant with the above action statements and the applicable TS Bases sections are also modified to reflect the proposed changts.
The May 20, 1991, letter provided clarifying inforn'ation that did not change the initial proposed no significant hazards consideration deterc. nation.
2.0 EVALUATION TS 3.8.2.2 and 3.8.2.4 provide LCOs and actions required when the LCOs cannot be met for the A.C. electrical busses and the D.C. electrical equipment and busses when the units are in Mode 5, shutdown; or Mode 6, refueling.
These action statements require that full containment integrity be established within 8-hours of determining that the required complement of A.C. or D.C. busses are not operable.
Containment integrity is defined, partially, in terms of TS 3.6.1.2, 3.6.1.3, and 3.6.4.1.
These TS are applicable only in Modes 1 through 4, and are not required to be met in Modes 5 and 6.
However, they are invoked through the current action statements of TS 3.8.2.2 and 3.8.2.4 for Modes 5 and 6 under certain conditions.
Thus, a discrepancy exists in I
9107080274 910627 ADOCK0500g7 DR
o
! requiring full containment integrity during shutdown or refueling (Modes 5 or
- 6) based on conditions and requirements during hot shutdown through operating conditions (Modes 4 through 1).
The need for the requested TS changes is based on the impracticality of implementing full containnent integrity during certain conditions which occur during cold shutdown or refueling (Modes 5 or 6).
These conditions would exist when the equipment necessary to establish containment integrity has been removed from service and the minimum A.C. or D.C. power systems required by the current TS 3.8.2.2 and 3.8.2.4 are not available.
Examples of these conditions are: (1) when the minimum A C. or D.C. power becomes unavailable during a 24-hour integr_ ted leak rate test (ILRT), it would not be possible to complete the ILET and reestablish containment integrity within the 8-hours specified in the current TSs (3.8.2.2 or 3.8.2.4); and (2) when performing repairs on a containment penetration which would require more than the 8-hours specified in the current TSs to reestablish containment integrity.
The licensee proposes to replace the requirement for full containment integrity, when in Modes 5 or 6, for TSs 3.8.2.2 and 3.8.2,4 with the requirement for containment penetration closure within the specified 8-hours.
In addition, the proposed changes include the requirement to immediately suspend all operations involving core alterations positive reactivity changes, movement of irradiated fuel including the movement of heavy loads over irradiated fuel, and immediate initiation of corrective actions to restore the required minimum number of electrical power busses to an operable and energized status.
A footnote is also proposed to allow completion of an ongoing action until a safe censervative position is established. TS 3.8.1.2, which does not have a current full containment integrity requirement, will be changed consistent with the proposed changes for TSs 3.8.2.2 and 3.8.2.4 The proposed changes to TS 3.9.4 will make the containnent penetration closure requirements consistent with the changes proposed for 3.8.1.2, 3.8.2.2 and 3.8.2.4 The licensee has provided the following safety assessment to support the requested changes.
During operation in Modes 1 through 4, a Design Basis Accident (DBA) could cause a release of radioactive material into the containment.
In these modes of operation, prevention against the release of this radioactive material to the environment is accomplished by maintaining containment integrity.
In Modes 5 and 6; however, the probability and consequences cf these events are lower because of the reactor coolant system pressure and temperature limitations.
A minimum complement of electrical power sources and distribution systems is established to assure adequate power for systems required to recover from a boron dilution event or a fuel handling incident, as discussed in the Calvert Cliffs, Units 1 and 2, Updated Final Safety Analysis Report, Sections 14.3 and 14.18, respectively.
A single power train / division is adequate when in Modes 5 and 6 because there is additional time available to restore power before fuel damage would occur. Additiorally, because of the lack of a containment pressurization potential, less stringent requirements are needed to isolate the containment from the outside atmosphere. These less stringent requirements are applied during core alterations, movement of irradiated fuel, and when the power distribution systems are degraded, as addressed in TS 3.9.4 relating to containment penetrations.
0
. When the number of energized A.C. or 0.C. power distribution systems are less than the minimum required by the TS, sufficient power may not be available to recover from a fuel handling accident.
Consequently, the proposed action statements require immediate suspension of core alterations, positive reactivity changes, movement of irradiated fuel in the containment and movement of loads over irradiated fuel within the containment.
These actions would preclude the occurrence of the postulated events and the need for establishing containment integrity.
However, containment penetration closure is proposed to provide additional conservatism and mitigation of unforeseen situations.
The requested TS changes take into consideration the need to prevent and/or control the consequences of a fuel handling incident or boron dilution event while in Modes 5 or 6.
As previously discussed, containment integrity is not practical nor necessary, under the conditions existing during Mode 5 or 6.
The proposed changes strengthen the controls to prevent the DBAs while in Modes 5 or 6 and modifies the means specified for controlling the consequences.
A containment boundary will continue to be provided when there are operations being conducted which could lead to a fuel handling incident or boron dilution event.
Containment penetration closure is equivalent to containment integrity under these circumstances.
Therefore, if the electrical distribution systems necessary to mitigate the consequences of one of these events become inoperable, the proposed TS would require suspension of such operations and the establishment of containment penetration closure, thereby removing the possibility of the event occurring, and mitigating any unforeseen situations.
The staff has determined that the proposed changes described above for TS 3.8.1.2, 3.8.2.2, 3.8.2.4, 3.9.4 and the supporting TS Bases, Sections 6.1.1 and 9.4 are acceptable.
This determination is based on (1) the expected conditions during Mode 5 and 6 operation; (2) the need to prevent or control the consequences of a fuel handling or boron dilution event; (3) the lack of a containment pressurization potential; (4) alternative actions (penetration closure, suspension of activities and initiation of corrective actions); and l
(5) the proposed changes correct current TS inconsistencies.
3.0 STATE-CONSULTATION In accordance with the Commission's regulations, the Maryland State official was notified of the proposed issuance of the amendments.
The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
The amendments change a requirement with respect tr 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 amendments involve 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 a l
.,a-k A - + - - - - > -..+
e
-2...
4..A u.-
4-proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment on such finding (56 FR 890).
Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR SI.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the anendments.
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) suc;.
activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor:
Daniel Mcdonald Date: June 27, 1991 l
l i
l l
. - - - -. -. ~. ~. _. -.. _ - -... -.
13 Mr. G. C. Creel-June 27, 1991 A copy of-the related Safety Evaluation is enclosed.
A Notice of Issuance will
-be-included in the Comission's next regular biweekly Federal Register notice.
j Sincerely.
Original Signed By:
Daniel G. Mcdonald, Senior Project Manager Project Directorate I-l Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation
Enclosures:
1.
Amendment No.155 to DPR-53 2.
Amendment No.135 to DPR-69 3.
Safety Evaluation ec w/ enclosures:
See next page DISTRIBUTION:-
=. pocket; fi le :
OGC OC/LFM8-NRC/ Local PDRs DHagan Plant File PDI.1 Reading GHill(4)
CCowgill
- SVarga Wanda Jones CMcCracken JACalvo CGrimes CVogan ACRS(10)
DMcDonald GPA/PA l
s,._-,_....._..-_.s.._.____..___..___-.~,..
0FC-
- PDI-1:LA
- PD
......__:0GC
...'...... :....... p.
- 'M
- 5PLB
- PDI-1:D
,. g.... -
i NAME gan
. Mcdonald:rse-:
- CMcCracken
- RAcapra
-r" 'aw
@k!$178UL_-.2Ak.YN1._L.h..'l1~2!.!_._.: MM
- YdOI UFFICIAL RECORD COPY
~
i
' Document Name:
CC1/2 AMEND 79236/37 l
-