ML19318C867
| ML19318C867 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 06/30/1980 |
| From: | SOUTHERN CALIFORNIA EDISON CO. |
| To: | |
| Shared Package | |
| ML13322A768 | List: |
| References | |
| NUDOCS 8007020372 | |
| Download: ML19318C867 (5) | |
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i DESCRIPTION OF PROPOSED CHANGE AND SAFETY ANALYSIS PROPOSED CHANGE NO. 93 TO THE TECHNICAL SPECIFICATIONS PROVISIONAL OPERATIONAL LICENSE DPR-13 This is a request to (1) revise Appendix A Technical Specification 1.0, DEFINITIONS, and (2) add a new Section 3 0, LIMITING CONDITIONS FOR OPERATION (GENERAL).
Reason for Proposed Change In an effort to clarify the meaning of the term Operable when used within the context of the Limiting Conditions for Operation, the NRC transmitted a request, by letter dated April 10, 1980, for submittal of proposed changes to the Technical Specifications which incorporate the requirements of the Model Technical Specifications included as Enclosure 1 to their letter. By letter dated May 15, 1980, a commitment was provided to the NRC for submittal of the requested proposed changes to the Technical Specifications.
Existing Specification Technica!. Specification 1.0 currently includes the following definition of the term Operable:
" Operable:
Operable means that the system or component is completely capable of performing its required function in its required manner."
Technical Specification 3 0 does not currently exist.
Proposed Specification Technical Specification 1.0 would be revised to include the following definition of the teru Operable:
" Operable:
A system, subsystem, train, component or device shall be Operable or have Operability when it is capable of performing its specified function (s).
Implicit in this definition shall be the assumption that all necessary attendant instrumentation, controls, normal and emergency electrical power sources, cooling or seal water, lubrication or other auxiliary equipment that are required for the system, subsystem, train, component or device to perform its function (s) are also capable of performing their related support function (s)."
D
A new Section 3.0 will be added to the Limiting Conditions for Operation to read:
"3 0 LIMITING CONDITIONS FOR OPERATION (GENERAL)
Applicability: Applies to the operational requirements to be implemented when specific actions are not identified within individual Limiting Conditions for Operation.
Objective:
To ensure that the station is placed in a safe condition when circumstances arise which are not identified within individual Limiting Conditions for Operation.
Specification:
A.
In the event a Limiting Condition for Operation and/or associated Action requirements cannot be satisfied because of circumstances in excess of those addressed in the specification, the unit shall be placed in at least Hot Shutdown within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, and in at least Cold Shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> unless corrective measures are completed that permit operation under the permissible Action statements for the specified time interval as measured from initial discovery or until the reactor is placed in a mode of operation in which the specification is not applica-ble. Exceptions to these requirements shall be stated in the individual specifications.
B.
When a system, subsystem, train, component or device is determined to be inoperable solely because its emergency power source is inoperable, or solely because its normal power source is inoperable, it may be considered Operable for the purpose of satisfying the requirements of its applicable Limiting Condition for Operation, provided:
(1) its corresponcing normal or emergency power source is Operable, and (2) all of its redundant system (s), subsystems (s),
train (s), component (s), and device (s) are Operable, or likewise satisfy the requirements of this specifi-cation. Unless both conditions (1) and (2) are satisfied, the unit shall be placed in at least Hot Shutdown within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, and in at least Cold Shutdown
,h within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. This specification is not applicable during the Cold Shutdown or Refueling modes of operation.
Basis:
Specification A delineates the action to be taken for circumstances not directly provided for in the Action statements and whose occurrence would violate the intent of the specification. For example, Technical Specifica-tion 3 3 requires in part that two recirculation pumps be i
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. Operable in order for the reactor to be made or maintained critical and provides explicit action requirements if one recirculation pump is inoperable.
Under the terms of Specification A, if more than one i
recirculation pump is inoperable, the unit is required to be in at least Hot Shutdown within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and in at least Cold Shutdown within 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> unless corrective measures are completed. It is assumed that the unit is brought to the required mode of operation within the required times by promptly initiating and carrying out the appropriate 4
action statement.
i Specification B delineates what additional conditions l
must be satisfied to permit operation to continue, consistent with the Action statements for power sources, l
when a normal or emergency power source is not Operable.
It specifically prohibits operation when one division is inoperable because its normal or emergency power source is inoperable and a system, subsystem, train, component, l
or device in another division is inoperable for another i
reason.
The proviraons of this specification permit the Action stateGercs associated with individual systems, subsys-tems, trains, components, or devices to be consistent with the Action statements of the associated eleatrical power source. It allows operation to be governed by the time limits of the Action statement associated with the Limiting Condition for Operation for the normal or emergency power source, not the individual Action state-ments for each system, subsystem, train, component or device that is determined to be inoperable solely because of the inoperability of its normal or emergency power source.
For example, Spectication 3 7 requires that two emergency diesel generators be Operable. The Action statement provides for a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> out-of-service time when one emergency diesel generator is not Operable. If the definition of Operable were applied without consideration of Specification B, all systems, subsystems, trains, components and devices supplied by the inoperable j
emergency power source would also be inoperable. This would dictate invoking the applicable Action statements for each of the applicable-Limiting Conditions for Operation. However, the provisions of Specification B permit the time limits for continued operation to be consistent with the Action statement for the inoperable emergency diesel generator instead, provided the other specified conditions are satisfied. In this case, this f
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would mean that the corresponding normal power source must be Operable, and all redundant systems, subsystems, trains, components and devices must be Operable, or otherwise satisfy Specification B (i.e., be capable of performing their design function and have at least one normal or one emergency power source Operable). If they are not satisfied, shutdown is required in accordance with this specification.
As a further example, Specification 3 7 requires in part that two physically independent offsite power lines be Operable. The Action statement provides a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> out-of-service time when both required offsite power lines are not Operable. If the definition of Operable were applied without consideration of Specification B, all systems, subsystems, trains, components and devices supplied by the inoperable normal power sources, both of the offsite power lines, would also be inoperable. This would dictate invoking the applicable Action statements for each of the applicable LCOs. However, the provisions of Specification B permit the time limits for continued operation to be consistent the the Action statement for the inoperable normal power sources instead, provided the other specified conditions are satisfied. In this case, this would mean that for one division, the emergency power source must be Operable (as must be the components supplied by the emergency power source) and all redundant systems, subsystems, trains, components and devices in j
the other division must be Operable, or likewise satisfy Specification B (i.e., be capable of performing their design functions and have an emergency power source Operable). In other words, both emergency power sources must be Operable and all redundant systems, subsystems, trains, components and devices in both divisions must also be Operable. If these conditions are not satisfied, shutdown is required in accordance with this specification.
. In the Cold Shutdown or Refueling modes of operation, Specification B is not applicable, and thus the individual Action o.atements for each applicable Limiting Condition for Operation in these modes of operation must be adhered to."
Safety Analysis The Technical Specifications are formulated to preserve the single failure
. criterion for systems that are relied upon in the Final Safety Analysis (FSA). By and large, the single failure criterion is preserved by specifying Limiting Conditions for Operation (LCOs) that require all redundant components 1
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of safety related systems to be Operable. When th) required redundancy is not maintained, either due to equipment failure or maintenance outage, action is required, within a specified tima.
'o change the operating mode of the plant to place it in a safe conditior.
ae specified time to take action, usually called the equipment out-of-service time, is a temporary relaxation of the single failure criterion, which, consistent with overall system reliability considerations, provides a limited time to fix equipment or otherwise make it Operable. If equipment can be returred to Operable status within the specified time, plant shutdown is not required.
LCOs are specified for each safety related system in the plant, and with few exceptions, the Action statements address single outages of components, trains or subsystems. For any particular system, the LCO does not address multiple outages of redundant components, nor does it address the effects of outages of any suppport systems - such as electrical power or cooling water - that are relied upon to maintain the Operability of the particular system. This is because of the large number of combinations of thecs types of outages that are possible. Instead, the Technical Specification employ general specifications and an explicit definition of the term Operable to encompass all such cases.
These provisions have been formulted to assure that no set of equipment outages would be allowed to persist that would result in the facility being in an unprotected condition. These specifications are contained in the Standard Technical Specifications and are incorporated into the San Onofre Unit 1 Technical Specifications by this Proposed Change. Illustrative examples of how these specifications apply are contained in the associated Bases.
Based upon the analysis provided above, it is concluded that (?) the proposed change does not involve an unreviewed safety question as defined in 10CFR50.59, nor does it present significant hazards considerations not described or implicit in the Final Safety Analysis, and (2) there is reasonable assurance that the health and safety of the public will not be endangered by the proposed change.
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