ML20212A770
| ML20212A770 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 02/18/1987 |
| From: | Myers T, Williams J TOLEDO EDISON CO. |
| To: | |
| Shared Package | |
| ML20212A747 | List: |
| References | |
| TAC-64851, NUDOCS 8703030411 | |
| Download: ML20212A770 (13) | |
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Docket No. 50-346 License No. NPF-3 Serial No'. 1353 Attachment APPLICATION FOR AMENDMENT TO FACILITY OPERATING LICENSE NO. NPF-3 FOR DAVIS-BESSE NUCLEAR POWER STATION UNIT NO. 1 Enclosed are requested changes to the Davis-Besse Nuclear Power Station, Unit No. 1, Facility Operating License No. NPF-3. Also included are the Safety Evaluation and'Significant Hazards Consideration.
The proposed changes (submitted under cover letter Serial No. 1353) concern:
Section 3/4.7, Plant Systems, Specification 3.7.1.7, Motor Driven Feedwater Pump System; Section 3/4.7, Plant Systems, Specification 4.7.1.7, Motor Driven Feedwater Pump System; Bases, Section B 3/4.7.1.7, Motor Driven Feedwater Pump System.
For J. Williams, Jr.
By h T. J. ye Sworn to and subscribed before me this 18th day of February, 1987.
t $ $) b/ b 1 l0 -
Notary Public, State of Ohio My commission expires /.k )
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l 8703030411 870210 l hDR ADOCK 05000346 PDH
Dockst No. 50-346 License No. NPF-3 Serial No. 1353 Attachment L
- ' The following information is provided to support issuance of the requested changes to the Davis-Besse Nuclear Power Station, Unit No. 1 Operating License No. NPF-3, Appendix A, Technical Specification Sections 3.7.1.7 and 4.7.1.7 and Bases Section B 3/4.7.1.7
A. Time required to implement: This change is to be effective 30 days after issuance of the License Amendment.
B. Reason for change (Facility Change Request No. 87-0031):
Revise Technical Specifications to include Motor Driven Feedwater Pump System Technical Specifications in accordance with Toledo Edison's commitment as stated in the Davis-Besse Course of Action (C0A) document, Revision 4, Appendix III.2, Question No. 10c (Serial No. 1208).
C. Safety Evaluation: See attached Safety Evaluation.
D. Significant Hazards Consideration: See attached Significant Hazards Consideration.
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Docket No. 50-346 License No. NPF-3 Serial No. 1353 Attachment SAFETY EVALUATION INTRODUCTION The purpose of this safety evaluation is to review a proposed change to the Davis-Besse Nuclear Power Station (DBNPS), Unit No. 1 Operating License, Appendix A, Technical Specifications to ensure that no unreviewed safety questions exist. This safety evaluation is being performed to meet the requirements of 10CFR50.59.
This License Amendment Request proposes adding Section 3/4.7.1.7, " Motor Driven Feedwater Pump System," to the Technical Specifications. This addition is consistent with commitments regarding Auxiliary Feedwater (AFW) System reliability made to the NRC in Revision 4 to the Davis-Besse Course of Action Document (Serial No. 1208, dated November 16, 1985) following the Davis-Besse June 9, 1985 event. The proposed Technical Specification for the Motor Driven Feedwater Pump (MDEP) System is similar to the Technical Specification for the AFW System. The proposed Technical Specification provides operability requirements for the MDFP System during Mode 1, 2 and 3 operations. If the MDFP is found to be inoperable, the proposed Technical Specification provides a Limiting Condition for Opera-tion (LCO) of restoring operability within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or placing the plant in hot shutdown within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. In order to determine and define operability, the proposed Technical Specification provides Surveil-lance Requirements for the MDFP System. The proposed Technical Specification provides the basis for including the MDFP in the Technical Specifications and briefly describes the MDFP modes of operation.
SYSTEMS AFFECTED Main Feedwater (MFW) Systen Auxiliary Feedwater (AFW) System Motor Driven Feedwater Pump (MDFP) System Reactor Coolant System (RCS)
REFERENCES Davis-Besse Nuclear Power Station, Unit No. 1 Operating License.
Appendix A Technical Specifications. Section 3/4.7.1.2 Davis-Besse Nuclear Power Station, Unit No. 1, Updated Safety Analysis Report, June, 1986 1
D:ckat No. 50-346 License No. NPF-3 Serial No. 1353 Attachment FUNCTIONS OF AFFECTED SYSTEMS The Main Feedwater (MFW) System, utilizing steam turbine driven Main Feed Pumps (MFPs), supplies the normal source of water to the steam generators (SGs) for conversion into steam. At low reactor power levels (typically below four percent), there is insufficient steam capacity to drive a MFP.
Prior to the installation of the MDFP, the electric motor-driven Startup Feedwater Pump (SUFP) was used to supply water to the SGs until sufficient steam was available to drive a MFP at a stabilized level. The MDFP is now used to supply feedwater to the SGs via the MFW System during plant startup and at low reactor power levels until sufficient steam is available to drive a MFP at a stabilized level.
The AFW System supplies auxiliary feedwater to the SGs when the MFW System is unavailable for decay heat removal or to establish natural circulation. The point of injection into the SG for AFW is much higher than that for the MFW so that it is much more effective in removing energy from the Reactor Coolant System (RCS). The AFW System can automatically initiate feeding the SGs. The AFW System is capable of cooling down the RCS so that the Decay Heat System can be initiated.
The MDFP is an electric motor-driven feed pump which can be aligned to either the MFW or the AFW System. The motor has multiple power sources available to it, including offsite power and both Emergency Diesel Generators, to ensure it is highly reliable. The motor can be started and stopped from either the control room or locally at the pump. The MDFP is sized so that it is capable of removing decay heat from the reactor as if it were another AFW pump. A throttle valve on the pump's discharge is controllable from either the control room or locally. Align-ment of the MDFP to either the MFW System or the AFW System is accomp-lished by manually positioning the appropriate system valves.
When supplying the MFW System, the MDFP's suction is aligned to the deaerator, and its discharge is aligned to the SGs via the MFW System.
Control of flow to each SG can be accomplished from the control room by manipulating valves in the MFW System. Cooling water for the MDFP is supplied from the Service Water System in this mode of operation.
When supplying the AFW System, the MDFP's suction is aligned to the Condensate Storage Tank (CST), and its discharge is aligned to both SGs via the AFW Systen piping. Cooling water for the MDFP is supplied from the pump's own discharge in this mode since the water from the CST is relatively cool. In this mode, control of the flow to individual SGs is by manual valve operations since the throttle valve on the pump's discharge can only control the pump's total discharge capacity and pressure.
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Dockat No. 50-346 License No. NPF-3 Serial No. 1353 Attachment By adding the MDFP and meeting the operability requirements as defined by the Surveillance Requirements of the proposed Technical Specification, the safe operation of Davis-Besse is enhanced. The pump adds diversity and redundancy to the feedwater sources to the SGs so that decay heat can be removed even in the event all other feedwater sources fail. The proposed Technical Specification ensures that pump and valve operability are verified and demonstrated on a periodic basis.
The RCS comes in direct contact with the reactor core and transfers the energy generated by the core to the water in the secondary side of the SGs. The energy being removed is generated by the fission process during power operations, and by nuclear decay processes during and after power
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operations. The decay heat must be removed after the reactor is shutdown to keep the reactor core adequately cooled.
EFFECTS ON SAFETY The MDFP can be used to supply either the MFW or the AFW System. When starting up the plant, the MDFP initially supplies all the feedwater to both SGs. Once reactor power is above about two to four percent, a MFP can be started and used for supplying MFW. While the MDFP is supplying feedwater to the SGs, control of the feedwater flow to each SG can be accomplished from-the control room by remotely manipulating MFW System valves. As reactor power rises, the second MFP is started and put into operation. The MDFP remains aligned to the MFW System until reactor power reaches 40 percent, where the MDFP suction is realigned from the deaerator to the Condensate Storage Tank, its discharge realigned to both SGs via the AFW System, and the pump's cooling water source realigned from the Service Water System to the pump's own discharge. All valve positioning required to realign the MDFP is performed by local manual valve operation.
The MDFP is then available as another source of water supply to the AFW System. When aligned to the AFW System, the only way to control flow to individual SGs is by local manual operation of valves. If the AFW System is required to operate during plant startup, the MDFP would be shifted over to the AFW System to take advantage of that system's greater heat removal effectiveness in the SGs. The MDFP can be started and stopped by operator action from either the control room or locally at the pump. The MDFP discharge flow can he throttled by operator action either from the
, control room or locally at the pump.
l l The proposed MDFP Technical Specification is similar to that applicable j to the AFW System. By meeting the Surveillance Requirements of the proposed Technical Specification, reliability of the MDFP System is I
ensured. Both the MDFP and the AFW Technical Specifications require a demonstration of pump operability and valve lineup verification on a j monthly basis (Specification 4.7.1.7a) and a complete system operability i demonstration every 18 months (Specification 4.7.1.7c). If any mainten-ance is performed on or changes made to either system which could impact its operability, a system operability verification is required to be j performed (Specification 4.7.1.7d).
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Docket No. 50-346 License No. NPF-3 Serial No. 1353 Attachment Because the MDFP is a manually actuated, electric motor-driven pump and the valves are operator manipulated only, differences exist between the AFW Technical Specification and the MDFP Technical Specification. Since the MDFP valves are positioned based on the reactor's power level (greater or less than 40 percent), additional requirements for valve position verification (Specification 4.7.1.7a) and quarterly power operated or automatic valve position control and pump operability testing (Specification 4.7.1.7b) are included in the MDFP Technical Specification. Because the MDFP is manually actuated, there are no automatic response capabilities or steam pressure interlock tests required, as for the AFW System. Complete operability demonstration is, however, still required.
The inclusion of this proposed Technical Specification will mean that instead of two of two AFW pumps being required to meet Technical Specification requirements, three of three pumps will be required to meet Technical Specification requirements. Previously, the inoperability of one of the two AFW pumps would place the plant in the 72-hour Action Statement of either restoring full operability or shutting down the plant. The MDFP Technical Specification addition would put the plant in a similar LCO if any one of the two AFW pumps or the MDFP became inoperable. This results in the MDFP being comparable to a backup AFW pump for the AFW System which effectively improves the overall reliab-ility of the AFW System and decreases the effects of AFW component failures.
In order to explain why the MDFP System has been included in the Tech-nical Specifications, a new Bases (Bases 3/4.7.1.7) has been added in the Bases Section of the Technical Specifications.
UNREVIEWED SAFETY QUESTION EVALUATION This Technical Specification revision, with its attendant operability requirements, LCO, and Surveillance Requirements, will not increase the probability of any previously analyzed accident. This is because there is no change in the method of plant operation for the MDFP when serving as a startup feedwater source. Since the plant will be operating as previously analyzed, there is no change in the probability of analyzed accidents occurring. When the source of feedwater has been shifted to the MFPs and the MDFP is aligned to the AFW System, the MDFP is in a manual standby mode and verified to be operable. This improves and controls its availability and reliability, thereby decreasing the proba-
! bility of experiencing undercooling events analyzed in the Davis-Besse Updated Safety Analysis Report (USAR). Because the MDFP is under l
manual operator control, there is no change in the probability of experiencing an overcooling event. The pump does not impact the proba-j bility of experiencing any other USAR analyzed accidents. The Surveil-lance Requirements are met by performing surveillance tests which are written and reviewed to ensure that they do not increase the probability of experiencing any previously analyzed accidents (10CFR50.59(a)(2)(i)) .
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'Dockst No. 50-346 License No. NPF-3 Serial No. 1353 Attachment The proposed Technical Specification change will not increase the conse-quences of any event previously analyzed in the Davis-Besse USAR because the system is manually controlled which will prevent it from affecting those events where its operation could worsen the consequences of the analyzed events (e.g., overcooling events). The system's availability reduces the consequences of events where AFW is desirable, since the MDFP can act as a backup or supplement to existing safety-related systems. Meet-ing the Surveillance Requirements of the proposed Technical Specification will not increase the consequences of any event previously analyzed in the Davis-Besse USAR since the surveillance tests will be written, reviewed, and implemented in a controlled manner so that they will not have any impact on the previously analyzed events (10CFR50.59(a)(2)(1)).
The proposed Technical Specification change will not increase the proba-bility of failure of equipment important to safety. This is because the MDFP is independent of the other AFW pumps, and is under manual control of the plant operators. Should this system fail, there are still multiple other sources of AFW (each AFW pump, using steam turbine drive) to supply the SGs. Additionally, by performing testing of the MDFP System, its reliability is demonstrated by verifying its operability on a periodic basis. The Surveillance Requirements of the proposed Technical Specifica-tion will be met by implementing test procedures which have been written and reviewed to ensure they do not increase the probability of failure of equipment important to safety (10CFR50.59(a)(2)(i)).
The proposed Technical Specification change will not increase the conse-quences of failure of equipment important to safety because it is adding an independent piece of equipment which can act as a backup or supple-ment to equipment important to safety. Its addition reduces the conse-quences of failure of equipment important to safety. The Surveillance Requirements will be accomplished by implementing test procedures which have been written and reviewed to ensure that they do not impact the consequences of failure of equipment important to safety when they are being performed (10CFR50.59(a)(2)(1)) .
The proposed Technical Specification revision does not create the possi-bility of an accident of a different type than previously analyzed in the Davis-Besse USAR. This is because the change is adding diversity and l
redundancy to the existing plant systems. Any possible effects on the plant of operating the MDFP as proposed have been analyzed. In the event of MDFP failure, the plant returns to its previously analyzed state.
Tests required to meet the Surveillance Requirements of the proposed Technical Specification will be written, reviewed, and implemented to preclude the possibility of an accident of a different type than prev-iously analyzed in the Davis-Besse USAR (10CFR50.59(a)(2)(ii)).
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Docket No. 50-346
. License No. NPF-3
! Serial No. 1353 Attachment The proposed Technical Specification revision does not increase the proba-bility of equipment malfunction of a different type than previously l analyzed in the Davis-Besse USAR. This is because there is no different equipment being added to the plant, and the method of control prevents equipment malfunctions from having any effects on the plant. The tests needed to meet the Surveillance Requirements of the proposed Technical Specification will be written, reviewed, and implemented so that they do not increase the probability of equipment malfunction of a different type than previously analyzed in the Davis-Besse USAR (10CFR50.59(a)(2)(ii)).
The proposed Technical Specification revision does not decrease the margin of safety as defined in the Bases for any Technical Specification because j it is adding a manually controlled, redundant, diverse method of dealing
, with accidents. By having this source of water available, the margin of i safety for events where insufficient feedwater is of concern is improved.
i For events where excessive feedwater is of concern, the manual control of
- the system prevents a decrease in the margin of safety. Tests required to i meet the Surveillance Requirements of the proposed Technical Specification j will be written, reviewed, and implemented so that they do n,ot decrease
- the margin of safety as defined in the Bases for any Technical Specifica-i tions (10CFR50.59(a)(2)(iii)) .
- CONCLUSION l Therefore, it is concluded that the proposed Technical Specification
, change does not create any unreviewed safety questions.
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Docket No. 50-346 License No. NPF-3 Serial-No. 1353 Attachment SIGNIFICANT HAZARDS CONSIDERATION INTRODUCTION The purpose of this License Amendment Request is to propose a change to the Davis-Besse Nuclear Power Station (DBNPS), Unit No. 1 Operating License, Appendix A, Technical Specifications. This License Amendment Request proposes adding Section 3/4.7.1.7, " Motor Driven Feedwater Pump System,"
to the Technical Specifications. This addition is consistant with commit-ments regarding Auxiliary Feedwater (AFW) System relia' i' 4 v made to the NRC in Revision 4 to the Davis-Besse Course of Action Do. snt (Serial No.
1208, dated November 16, 1985) following the Davis-Besse - ne 9, 1985 event. The proposed Technical Specification for the Motor Driven Feedwater Pump (MDFP) System is similar to the Technical Specification for the AFW System. The proposed Technical Specification provides operability require-ments for the MDFP System during Mode 1, 2 and 3 operations. If the MDFP is found to be inoperable, the proposed Technical Specification provides a Limiting Condition for Operation (LCO) of restoring operability within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or placing the plant in hot shutdown within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. In order to determine and define operability, the proposed Technical Specifi-cation provides Surveillance Requirements for the MDFP System. The proposed Technical Specification provides the basis for including the MDFP in-the Technical Specifications and briefly describes the MDFP modes of operation.
SYSTEMS AFFECTED Main Feedwater (MFW) System Auxiliary Feedwater (AFW) System Motor Driven Feedwater Pump (MDFP) System Reactor Coolant System (RCS)
REFERENCES Davis-Besse Nuclear Power Station, Unit No. 1 Operating License, Appendix A Technical Specifications, Section 3/4.7.1.2
! Davis-Besse Nuclear Power Station, Unit No. 1 Updated Safety Analysis Report i
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Docket No. 50-346 License No. NPF-3
!- Serial No. 1353 Attachment 4
FUNCTIONS OF AFFECTED SYSTEMS 1
The MFW System, utilizing steam turbine driven Main Feed Pumps (MFPs),
supplies the normal source of water to the steam generators (SGs) for I
conversion into steam. At low reactor power' levels (typically below four percent), there is insufficient steam capacity to drive a MFP. Prior to the installation of the MDFP, the electric motor-driven Startup Feedwater
- i. Pump (SUFP) was used to supply water to the SGs until sufficient steam was available to drive a MFP at a stabilized level. The MDFP is now used to supply feedwater to the SGs via the MFW System during plant startup and at low reactor power levels until sufficient steam is available to drive a MFP at a stabilized level.
- . The AFW System supplies auxiliary feedwater to the SGs when the MFW
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System is unavailable for decay heat removal or to establish natural circulation. The point of injection into the SG for AFW is much higher
< than that for the MFW so that it is much more effective in removing energy I-from the RCS. The AFW System can automatically initiate feeding the SGs. The AFW System is' capable of cooling down the RCS so that the Decay i Heat System can be initiated.
l The MDFP is an electric motor-driven feed pump which can be aligned to
, either the MFW or the AFW System. The motor has multiple power sources available-to it, including offsite power and both Emergency Diesel i Generators, to ensure it is highly reliable. The motor can be started j and stopped from either the control room or locally at the pump. The
- MDFP is sized so that it is capable of removing decay heat from the i reactor as if it were another AFW pump. A throttle valve on the pump's j discharge is controllable from either the control room or locally. Align-ment of the MDFP to either the MFW System or the AFW System is accomp-lished by manually positioning the appropriate system valves.
When supplying the MFW System, the MDFP's suction is aligned to the deaerator, and its discharge is aligned to the SGs via the MFW System.
Control of flow to each SG can be accomplished from the control room by manipulating valves in the MFW System. Cooling water for the MDFP is j supplied from the Service Water System in this mode of operation.
i-I When supplying the AFW System, the MDFP's suction is aligned to the Condensate Storage Tank (CST), and its discharge is aligned to both SGs j via the AFW System piping. Cooling water for the MDFP is supplied from the pump's own discharge in this mode since the water from the CST is l relatively cool. In this mode, control of the flow to individual SGs is i by manual valve operations since the throttle valve on the pump's i discharge can only control the pump's total discharge capacity and j pressure.
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Docket No. 50-346 License No. NPF-3 Serial No. 1353 Attachment By adding the MDFP and meeting the operability requirements as defined by the Surveillance Requirements of the proposed Technical Specification, the safe operation of Davis-Besse is enhanced. The pump adds diversity and redundancy to the feedwater sources to the SGs so that decay heat can be removed even in the event all other feedwater sources fail. The proposed Technical Specification ensures that pump and valve operability are verified and demonstrated on a periodic basis.
The RCS comes in direct contact with the reactor core and transfers the energy generated by the core to the water in the secondary side of the SGs. The energy being removed is generated by the fission process during power operations, and by nuclear decay processes during and after power operations. The decay heat must be removed after the reactor is shutdown to keep the reactor core adequately cooled.
EFFECTS ON SAFETY The MDFP can be used to supply either the MEW or the AFW System. When starting up the plant, the MDFP initially supplies all the feedwater to both SGs. Once reactor power is above about two to four percent, a MFP can be started and used for supplying MFW. While the MDFP is supplying feedwater to the SGs, control of the feedwater flow to each SG can be accomplished from the control room by remotely manipulating MFW System valves. As reactor power rises, the second MFP is started and put into operation. The MDFP remains aligned to the MFW System until reactor power reaches 40 percent, where the MDFP suction is realigned from the deaerator to the Condensate Storage Tank, its discharge realigned to both SGs via the AFW System, and the rump's cooling water source realigned from the Service Water System to the pump's own discharge. All valve positioning required to realign the MDFP is performed by local manual valve operation.
The MDFP is then available as another source of water supply to the AFW System. When aligned to the AFW System, the only way to control flow to individual SGs is by local manual operation of valves. If the AFW System l is required to operate during plant startup, the MDFP would be shifted
! over to the AFW System to take advantage of that system's greater heat l removal effectiveness in the SGs. The MDFP can be started and stopped by operator action from either the control room or locally at the pump. The l MDFP discharge flow can be throttled by operator action either from the l
control room or locally at the pump.
The proposed MDFP Technical Specification is similar to that applicable to the AFW System. By meeting the Surveillance Requirements of the proposed Technical Specification, reliability of the MDFP System is ensured. Both the MDFP and the AFW Technical Specifications require a l demonstration of pump operability and valve lineup verification on a monthly basis (Specification 4.7.1.7a) and a complete system operability demonstration every 18 months (Specification 4.7.1.7c). If any mainten-i ance is performed on or changes made to either system which could impact l its operability, a system operability verification is required to be performed (Specification 4.7.1.7d).
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Docket No. 50-346 License No. NPF-3 Serial No. 1353 Attachment Because the MDFP is a manually actuated, electric motor-driven pump and the valves are operator manipulated only, differences exist between the AFW Technical Specification and the MDFP Technical Specification. Since the MDFP valves are positioned based on the reactor's power level (greater or less than 40 percent), additional requirements for valve position verification (Specification 4.7.1.7a) and quarterly power operated or automatic valve position control and pump operability testing (Specification 4.7.1.7b) are included in the MDFP Technical Specification. Because the MDFP is manually actuated, there are no automatic response capabilities or steam pressure interlock tests required, as for the AFW System. Comp 1cte operability demonstration is, however, still required.
The inclusion of this proposed Technical Specification will mean that instead of two of two AFW pumps being required to meet Technical Specification requirements, three of three pumps will be required to meet Technical Specification requirements. Previously, the inoperability of one of the two IFF pumps would place the plant in the 72-hour Action Statement of eith*r restoring full operability or shutting down the plant. The MDFP lechnical Specification addition would put the plant in a similar LCO if any one of the two AFW pumps or the MDFP became inoperable. This results in the MDFP being comparable to a backup AFW pump for the AFW System which effectively improves the overall reliab-ility of the AFW System and decreases the effects of AFW component failures.
In order to explain why the MDFP System has been included in the Tech-nical Specifications, a new Bases (Bases 3/4.7.1.7) has been added in the Bases Section of the Technical Specifications.
SIGNIFICANT HAZARDS CONSIDERATION The proposed changes do not involve a significant hazards consideration because the operation of the Davis-Besse Nuclear Power Station, Unit No. 1, in accordance with these changes would not:
- 1. Involve a significant increase in the probability or consequences of an accident previously evaluated (10CFR50.92(c)(1)).
The accident conditions and assumptions are not affected by the proposed Technical Specification changes. There is no change in the method of plant operation for the MDFP when serving as a startup feedwater source. The system is manually controlled which will prevent it from affecting those events where its operation could worsen the probability or consequences of the analyzed events (e.g.,
overcooling). Meeting the Surveillance Requirements of the proposed Technical Specification will not increase the probability or consequences of any event previously analyzed in the Davis-Besse USAR since the surveillance tests will be written, reviewed, and impicmented in a controlled manner so that they will not have any impact on the previously analyzed events.
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D;ckst No. 50-346 License No. NPF-3 Serial No. 1353 Attachment
- 2. Create the possibility of a new or different kind of accident from any previously evaluated (10CFR50.92(c)(2)) .
The proposed Technical Specification revision does not create the possibility of an accident of a different type than previously evaluated in the Davis-Besse USAR. This is because the Technical Specification change reflects the added diversity and redundancy to the existing plant systems. Any possible effects on the plant of operating the MDFP as proposed have been analyzed. Tests required to meet the Surveillance Requirements of the proposed Technical Specifi-cation will be written, reviewed, and implemented to preclude the possibility of an accident of a different type than previously analyzed in the Davis-Besse USAR.
- 3. Involve a significant reduction in a margin of safety (10CFR50.92(c) (3)) .
By adding a manually controlled, redundant source of water, the margin of safety for events where insufficient feedwater is of concern is improved. In events where excessive feedwater is of concern, the manual control of the system prevents a decrease in the margin of safety. The proposed Technical Specification does not result in a significant reduction in a margin of safety because the change simply adds the existing MDFP System under the Limiting Conditions for Operation and Surveillance Requirements of Appendix A Technical Specifications. Tests required to meet the Surveillance Requirements of the proposed Technical Specification will be written, reviewed, and implemented so that they do not decrease the margin of safety as defined in the Bases for any Technical Specification.
CONCLUSION On the basis of the above, Toledo Edison has determined that the amendment request does not involve a significant hazards consideration.
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