ML18153D170
| ML18153D170 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 11/10/1992 |
| From: | VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | |
| Shared Package | |
| ML18153D169 | List: |
| References | |
| NUDOCS 9211160383 | |
| Download: ML18153D170 (9) | |
Text
e ATTACHMENT 1 PROPOSED TECHNICAL SPECIFICATION CHANGES 9211160383 921110 PDR ADOCK 05000280 p PDR
e TS 3.14-2
- 5. Two service water flow paths to the charging pump service water subsystem are OPERABLE.
- 6. Two service water flow paths to the recirculation spray subsystems are OPERABLE.
B. The requirements of Specification 3.14.A.4 may be modified to allow one Emergency Service Water pump to remain inoperable for a period not to exceed 7 days. If this pump is not OPERABLE in 7 days, then place both units in HOT SHUTDOWN within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the next 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
The requirements of 3.14.A.4 may be modified to have two Emergency Service Water pumps OPERABLE with one unit in COLD SHUTDOWN with combined Spent Fuel pit and shutdown unit decay heat loads of 25 million BTU/HR or less. One of the two remaining pumps may be inoperable for a period not to exceed 7 days. If this pump is not OPERABLE in 7 days, then place the operating unit in HOT SHUTDOWN within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the next 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
C. There shall be an operating service water flow path to and from one operating main control and emergency switchgear rooms air conditioning condenser and at least one OPERA~LE service water flow path to and from at least one OPERABLE main control and emergency switchgear rooms air conditioning condenser whenever fuel is loaded in the reactor core. Refer to Section 3.23.C for air conditioning system operability requirements above COLD SHUTDOWN.
D. The requirements of Specifications 3.14.A.5, 3.14.A.6, and 3.14.C may be modified to allow unit operation with only one OPERABLE flow path to the charging pump service water subsystem, the recirculation spray subsystems, and to the main control and emergency switchgear rooms air conditioning condensers. If the affected systems are not restored. to the requirements of Specificatio'nS 3.14.A.5, 3.14.A.6, and 3.14.C within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, Amendment Nos.
e TS 3.14-3 the reactor shall be placed in HOT SHUTDOWN. If the requirements of Specifications 3.14.A.5, 3.14.A.6, and 3.14.C are not met within an additional 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, the reactor shall be placed in COLD SHUTDOWN.
The Circulating and Service Water Systems are designed for the removal of heat resulting from the operation of various systems and components of either or both of the units. Untreated water, supplied from the James River and stored in the high level intake canal is circulated by gravity through the recirculation spray coolers and the bearing cooling water heat exchangers and to the charging pumps lubricating oil cooler service water pumps which supply service water to the charging pump lube oil coolers.
In addition, the Circulating and Service Water Systems supply cooling water to the component cooling water heat exchangers and to the main control and emergency switchgear rooms air conditioning condensers. The Component Cooling heat exchangers are used during normal plant operations to cool various station components and when in shutdown to remove residual heat from the reactor. Component Cooling is not required o'n the accident unit during a loss-of-coolant accident. If the loss-of-coolant accident is coincident with a loss of off-site power, the nonaccident unit will be maintained at HOT SHUTDOWN with the ability to reach COLD SHUTDOWN.
The long term Service Water requirement for a loss-of-coolant accident in one unit with simultaneous loss-of-station power and the second unit being brought to HOT SHUTDOWN is greater than 15,000 gpm. Additional Service Water is necessary to bring the nonaccident unit to COLD SHUTDOWN. Three diesel driven Emergency Service Water pumps with a design capacity of 15,000 gpm each, are provided to supply water to the High Level Intake canal during a loss-of-station power incident. Thus, considering the single active failure of one pump, three Emergency Service Water pumps are required to be OPERABLE. The allowed outage time of 7 days provides operational flexibility to allow for repairs up to and Amendment Nos.
ATTACHMENT 2 DISCUSSION AND SIGNIFICANT HAZARDS CONSIDERATION EVALUATION
e Introduction The proposed change would specify a Limiting Condition for Operation (LCO) for operable Service Water flow paths to the main control and emergency switchgear rooms air conditioning condensers (Technical Specification 3.14.C) in lieu of Technical Specification 3.0.1. The purpose of the change is to provide a system specific LCO which permits one of the two service water flow paths to the main control and emergency switchgear rooms air conditioning condensers to be removed from service for system maintenance. In the near term, the change would facilitate replacement of service water strainer, 1-VS-S-1 B, and its associated isolation valves, 2-SW-305 and 2-SW-306. Technical Specification 3.14.C states, "There shall be operating service water flow path to and from one operating main control and emergency switchgear rooms air conditioning condenser and at least one operable service water flow path to and from at least one operable main control and emergency switchgear rooms air conditioning condenser whenever fuel is loaded in the reactor core. Refer to Section 3.23.C for air conditioning system operability requirements above cold shutdown." The proposed change will provide an explicit LCO with a specific Action Statement for this subsystem.
Description of Change
- Terms defined in Technical Specification Section 1.0 are being shown in all capital letters.
- Action Statement 3.14.C.1 and its associated footnotes are being deleted since these provisions expired on March 31, 1990. As a consequence, page TS 3.14-2a will be deleted as well.
- The requirements of 3.14.C concerning the service water flow paths to the main control and emergency switchgear rooms air conditioning condensers are being added to Action Statement 3.14.D. Thus, one of the subject flow paths will be allowed to be out of service for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> before HOT SHUTDOWN is required and an additional 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> before COLD SHUTDOWN is required.
Page 1 of 5
Discussion of Change Limiting Conditions for Operation (LCO) - Technical Specification 3.14.C The present wording of this LCO does not provide a specific Action Statement other than the understood default to Technical Specification 3.0.1.
The likelihood that a LOCA or other accident will occur is neither increased or decreased by this Technical Specification change. This Technical Specification change will not negatively impact the reliability of the service water supply to the main control and emergency switchgear rooms air conditioning condensers. Thus, there is not a significant increase in the probability of a previously analyzed accident due to this change. Providing an Action Statement which in effect extends the time limitation of an LCO does not impact the outcome of an accident scenario because single failure is not applied as a design criterion to the redundant train of a system while it is in an Action Statement. Thus, the consequences of a malfunction of equipment important to safety previously evaluated in the UFSAR are not increased by this change because the redundant train is fully capable of performing the system function. Despite the ability of one train of service water supply to provide sufficient flow to these subsystems, removing the operating/operable redundancy requirement for a period of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> does increase the probability of a loss of the service water supply during that
- time. As presently specified, by not having the ability to place a redundant train in service immediately, the requirements of Technical Specification 3.0.1 would have to be applied.
Extending an Action Statement time limitation of an existing LCO does not produce a new accident scenario or produce a new type of equipment malfunction.
The Basis Section of Technical Specification 3.14 does not address the redundant service water supply requirement or the ability of a single train to provide the required service water flow.
Since the reduction in redundancy of the subject service water supply subsystems would be detrimental to recovery of cooling capacity during the extended Action Statement time period, the probability of a malfunction of equipment important to safety previously evaluated in the UFSAR would be increased. Therefore, the proposed Page 2 of 5
-Technical Specification change package does involve an unreviewed safety question as determined by the criteria of 10 CFR 50.59.
Although an unreviewed safety question is involved, the change is considered to be beneficial to safe plant operation. Entry into Technical Specification 3.0.1 requires that immediate actions be taken for shutdown. The change allows performance of maintenance on components which cannot be isolated individually by providing time to isolate a train for maintenance. Routinely performing this maintenance will increase the reliability of the service water supply to the main control and emergency switchgear rooms air conditioning condensers. The increase in the reliability of the service water supply outweighs the slight increase in risk during the removal of one service water flow path from service.
SIGNIFICANT HAZARDS CONSIDERATION The standards used to arrive at a determination that a Technical Specification change request involves no significant hazards* consideration are included in the Commission's regulations, 10 CFR 50.92, which states that no significant hazards considerations are involved if the operation of the facility in accordance with the proposed amendment would not (1) involve a significant increase in the probability 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. Each standard is addressed as follows:
(1) Operation of the facility in accordance with the modified technical specifications would not involve a significant increase in the probability or consequences of an accident previously evaluated.
The likelihood that a LOCA or other accident will occur is neither increased or decreased by this Technical Specification change. This Technical Specification change will not negatively impact the reliability of the service water supply to the main control and emergency switchgear rooms air conditioning condensers.
Thus, there is not a significant increase in the probability of a previously analyzed accident due to this change. Providing an Action Statement which in effect extends the time limitation of an LCO does not impact the outcome of an accident scenario since single failure is not applied as a design criterion to the Page 3 of 5
redundant train of a system already in an Action Statement. Thus, the consequences of a malfunction of equipment important to safety previously evaluated in the UFSAR are not increased by this change because the redundant train is fully capable of performing the system function. Despite the ability of one train of service water supply to provide sufficient flow to these subsystems, providing an allowed outage time which effectively removes the operating/operable redundancy requirement for a period of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> does slightly increase the probability of a complete loss of the service water supply during that time. As presently specified, by not having the ability to place a redundant train in service immediately, the requirements of Technical Specification 3.0.1 would have to be applied.
The proposed change is considered to be beneficial to safe plant operation.
Providing an allowed outage time permits performance of maintenance on components which cannot be isolated individually. The capability to perform this maintenance should result in an increase in the reliability of the service water supply to the main control and emergency switchgear rooms air conditioning condensers. This potential increase in the reliability of the service water supply outweighs the slight increase in the probability that the service water supply header may become unavailable during the removal of one service water flow path from service.
The proposed administrative changes do not affect equipment or its operation, and, thus, do not affect the probabilities or consequences of an accident.
Therefore, we conclude that this change does not significantly increase the probabilities or consequences of an accident.
(2) Operation of the facility in accordance with the modified technical specifications would not create the possibility of a new or different kind of accident from any accident previously evaluated.
The proposed changes do not involve changes to the physical plant or operations. Extending an Action Statement time limitation of an existing LCO does not produce a new accident scenario or produce a new type of equipment malfunction. Also, this change does not alter any existing accident scenarios.
The proposed administrative changes do not affect equipment or its operation, Page 4 of 5
- and, thus, do not create the possibility of a new or different kind of accident.
Therefore, the proposed changes do not create the possibility of a new or different kind of accident.
(3) Operation of the facility in accordance with the modified technical specifications would not involve a significant reduction in a margin of safety.
The Basis Section of Technical Specification 3.14 does not address the redundant service water supply requirement or the ability of one train to supply the required service water flow. Furthermore, since an adequate supply of service water to the main control and emergency switchgear rooms air conditioning condensers will continue to be provided, the existing analysis envelope remains bounding. The proposed administrative changes do not affect equipment or its operation, and, thus, do not involve any reduction in the margin of safety.
Therefore, use of the proposed Technical Specification would not involve any reduction in the margin of safety.
In addition, we believe this change request is of the type described in the Federal Register Notice of March 6, 1986 (51 FR 7744) as an example of amendments that are considered not likely to involve significant hazards considerations. In particular, example (i) applies to the capitalization of defined terms and deletion of expired footnotes and Action Statements as purely administrative changes to technical specifications.
Based on the above, we have determined that the Technical Specification change request does not (1) involve a significant increase in the probability or consequences of an accident previously evaluated, (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. Therefore, this Technical Specification change request does not involve a significant hazards consideration.
Page 5 of 5