ML20217G460
| ML20217G460 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun  |
| Issue date: | 10/03/1997 |
| From: | OMAHA PUBLIC POWER DISTRICT |
| To: | |
| Shared Package | |
| ML20217G451 | List: |
| References | |
| NUDOCS 9710100214 | |
| Download: ML20217G460 (11) | |
Text
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3.0
.SURVEII I ANCE MFOUIREMENTS 3.9 Aurillary Feedwater System Applicabilhv Applies to periodic testing requireme<its of the turbine-driven and motor-driven auxiliary feedwater pumps.
Oblective To verify the operability of the auxiliary feedwater (AFW) system and its ability to respond properly when required.
Specifications
-(1)
The position of valves necessary to ensure auxiliary feedwater How to the steam generators shall be verified b thly inspection. Anytime maintenance is performed on the auxilla a
stem which alters valve alignments, an operator shall check that e affected
- W system valves are properly aligned, to ensure AFW flow to t e
rators, and a second operator shall independently verify proper lve alignment.
I (2)
The operability of the motor-driven auxillary feedwater pump and the steam 4eNg; gc p; ;;% Lgl: k ic-14 ;u k a; ice;; 40 p;ig ak ec h W
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ge7. ;er p;,;,re a;s ;c4 ;;,e... Cow.
(3)
The operability of auxiliary feedwater pumps' steam generator level regulating "s
CV ll 7A, HCV-1107B ICV-Il08A. IICV-B, a auxiliary feedwater cross-tie valve V-384 s la GIharmed a;, ;. ev, jT;.7-
'accordance,with the innervice Teating Pgr
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&= 300"r, ;k rr.o;cc-driver. auai::arj rcedwa;cr pu.r.p ;L:: k ;c; cJ ;c h verify ;k r.orar. Cow pa;h for auxi iarj fccJw;;cs ;a ;k ;;c... ger.cr ;are, yerityith proper alignment of_the required AFY tiow paths by,yerifying flow fro _m!the emergency feedwater storage tank to cach steam generator priorito
[ raishig_the reactor coolant temperature (Tdabove 300%whenever the. unit,has been in. MODE,4:and/or 5 for greater than 30; days {
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9710100214 971003 PDR ADOCK 05000285 p
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(5)
On a refueling frequency:
a.
Verify that each automatic valve in the flow path actuates to its correct position upon receipt of each auxiliary feedwater actuation test signal, b.
Verify that each auxiliary feedwater pump starts as designed automatically upon receipt of each auxiliary feedwater actuation test signal.
3-62 Amendment No. 49;6+;90:157 i
3.0 SURVEILLANCE REOUIR%JENTS 3.9 Auxiliary Feedwalrr System (Continued) llails The basic safety related function of the auxiliary feedwater (AFW) system is to provide an alternate source of feedwater to the steam generators in the event of a loss of main feedwater. The auxiliary feedwater system is designed so that a single active failure coincident with a loss of offsite power will not prevent a safe plant shutdown.
Specification 3.9(1)
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The valve position verifications performed monthly and-fellowing+meliarydeedwater system-maintenanee will confirm the availability of an auxiliary feedwater flow path to I
the steam generators. Following AFW system maintenance, the affected valves are he correct position; Specilleation 3.9(2)
The testing of the auxiliary feedwater pumps every mon -andsfter-cold-shuttkens will verify their operability by recirculating water to the eme er e
i o age tank.
_f. y Proper functioning of the AFW steam turbine admission valve and star'.ing of the feedwater pump.will_ demonstrate the integrity of the steam driven pump. Verification of correct operation will be made both from instrumentation within the main control room and direct visual observation of the pumps. &W'
- - CO w:1 Specification 3.9(3)
- 3pw=_~ =n
Operating AFW system cross tie valve IICV-1384 and the regulating valves (ItCV-Il07A. IICV-Il07B, llCV-1108A and ilCV-Il08B) one at a time every-thrcc ;ncaths andmftcr cold shutdowns in accordance with the Inservice Testing Program will onfi a n-hw th-ttH in cacruters nd operability of the valves.
Specification 3.9(4) h%
This surveillance ensures that the AFW system is properly aligned by verifying How from the emergency feedwater storage tank.to each steam generator. The required flow paths are through valve IICV-1384 and valves llCV-1105/11CV 1106 using FW-6.:
The surveillance is performed prior to raising the reactor coolant temperature (T,)
above 300*F whenever the reactor coolant temperature has been below 210*F for greater than 30 days. OPERABILITY of the AFW flow paths must be verified before sufficient core heat is ;;erierated that would tequire.the operation of the AFW system during a subsequent shutdown.
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Prop,s fune;;enh.g of ic a:c ;n :arblac da;;;;!sr. v;lve and ;;;r;;ng of :he fecJv.;;ci pa;ap will d,...oa;;s. ic ia; gri;y of ic ;;ce;n dri'.cr. pe;ar. Vert.ce:!an of corre ;
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Specification 3_.9(5) l This surveillance ensures that the.AFW pumps will stant,'and automatic val.ves will 1
mpositions in the event of any, accident or transient that generates an AFASr:The sur"eil!ance demonstrates that AFW pumps FW 6, and FW-10 start,;a_nd valves HCyf 1107A/_B and HCV-11.08A/B actuate to their correct position automatically,;on_ a test I
pigna_1.VThe. test is accomplished by utilizing ~ overlapping _ tents to verify that the instmmentation, valves and motor driven pump are OPERABLE.with the steam 1
(t turbine <triven pump tested separately to verify its OPERABILITyMhe.reibeling frequency is, based on the need to perform this' surveillance under the conditions that apply during a unit. outage.and the potential for an unplanned _ transient _ if.the surveillance wem performed with the reactor at_ powerEThislfmquency is, acceptable; based on the design reliability and operating experience,of the; equipment; References (1) USAR. Section 9.4 (2) Technical Specification 2.5 -
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i 3-62a Amendment No. 49,64,9070 4 i
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U.S. Nuc' ear Regulatory Comission LIC-97-0155 l
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DISCUSSION, JUSTIFICATION AND NO SIGNIFICANT HAZARDS CONSIDERATION l
DISCUSSION AND JUSTIFICATION l
The Omaha Public Power District (OPPD) proposes to revise the Fort Calhoun Station (FCS) Unit No.1 Technical Specifications (TS) Surveillance 3.9.
" Auxiliary Feedwater System." to clarify what flow paths are required to be tested.
Additionally it is proposed to revise the Auxiliary Feedwater (AFW)
Jumps surveillance description to delete the specific discharge pressure.
BACKGROUND FC5 has two safety related AFW pumps, oae motor-driven, and one turbine driven.
In addition, there is a diesel driven non safety related pump. All three pumps are 100% capacity pumps, capable of providing sufficient feedwater to cool the plant to conditions required to initiate the shutdown coolirg system.
The two safety related pumps use the Emergency reedwater Storage Tank (EFWST) as their source of feedwater, whereas the non safety related pump utilizes the condensate storage tank.
There are several flow paths from the AFW pumps to each steam generator.
Both safety related AFW pumps feed into a common header which then may go into several flow paths.
One set of flow paths to the steam generators is through HCV-1384 to valves HCV-1105 (to steam generator RC-2A) and HCV-1106 (to steam generator RC-28) utilizing the Main Feedwater piping.
Additional flow paths are those actuated by a Auxiliary Feedwater Actuation Signal (AFAS).
These flow paths are through valves HCV-1107A/HCV-1107B and HCV-1108A/HCV-1108B.
AFW PUMP OPERATION The speed of the turbine-driven AFW pump is governed by a differential pressure controller which maintains the pump discharge pressure at a fixed differential pressure greater than the steam pressure entering the turbine.
The original Final Safety Analysis ' e sort (FSAR) stated that the differential pressure could be set in the field, and that it would be set so that the pump discharge is about 40 psi above the steam generator pressure at rated flow.
The motor-driven AFW pump is a constant speed pump with a shutoff pressure of approximately 1200 psig.
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1 DISCUSSION AND JUSTIFICATION (Continued):
TS 3.9(2) requires that the operability of both the motor driven and steam turbine driven AFW pump be confirmed monthly and that the discharge pressure be verified to be at least 40 psig above the steam generator pressure at rated flow.
The requirement to be at least 40 psig above the steam generator pressure was incorporated by Change Number 7 to the TS. dated February 28, 1974, to correspond to the setting for the pneumatic speed control loop specified in the original FSAR.
On a loss of instrument air to the speed control loop, the steam turbine driven AFW pump goes to maximum speed as
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1 controlled by the speed limiting governor.
The 40 psig value is not related to the operation of the motor-driven AFW pump.
PROPOSED CHANGES RELATED TO AFW PUMP ACCEPTANCE CRITERIA l
It is proposed to revise TS 3.9(2) to delete the 40 psig specified for the AFW pump's discharge pressure.
Pump performance parameters and the pump's ability to function under post accident conditions are measured and evaluated l
quarterly under the station's inservice Testing (IST) program.
These
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quarterly surveillance tests verify that sufficient head is developed to I
inject an adequate supply of feedwater into the steam generators under worst case pressures at the point when auxiliary feedwater is required.
Because of this extensive quarterly testing. it is not necessary to verify on a monthly basis that the pump develops a specified amount of head.
TESTING OF AFW FLOW PATHS TS 3.9(4) requires that the motor driven auxiliary feedwater pump be tested following cold shutdown to verify the normal flow path to the steam generators.
This requirement was incorporated in the TS in Amendment 49 in response to NUREG-0635 ' Generic Evaluation of Feedwater Transients and Small Break Loss of Coolant Accidents in Combustion Engineering Designed Operating Plants." Recommendation GS-6(2) from NUREG-0635 was issued to address a concern that the AFW systems were not being properly restored to operable conditions following test or maintenance.
To address this concern, it was recommended that licensees should propose TS to assure that, prior to plant startup following an extended cold shutdown, a flow test would be performed to verify the normal flow path from the primary AFW system water source to the steam generators.
TS 3.9(5) requires that each auxiliary feedwater pump starts, and each automatic valve in the flow path actuates to its correct position upon receipt of auxiliary feedwater actuation test.
This requirement was incorporated in the TS in Amendment 54 in response to NUREG-0737 Item II.E.1.2.1.B.
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DISCUSSION AND JUSTIFICATION (Continued):
The requirement to verify the normal flow paths are operable is accomplished prior to the applicability of the specification (prior to 300'F) by utilizing the motor driven AFW pump and the flow paths from the EFWST to the steam generators through valves HCV 1105 and HCV-1106 utilizing the Main Feedwater piping.
Since both safety related AFW pumps feed into a common header, only the motor driven AFW pump is necessary to verify these flow paths.
Prior to reactor critical, after steam is available, the turbine driven AFW pump is tested by recirculating water from the EFWST.
PROPOSED CHANGES RELATED TO AFW FLOW PATHS It is proposed to revise TS 3.9(4) and the Basis Section to provide clarification on which flow paths are applicable for the individual surveillances. TS 3.9(4) requires the " normal" flow path be tested utilizing the motor driven AFW pump: however, the basis incorrectly states " testing of AFW pumps after cold shutdown," which implies both pumps are tested.
Additionally, TS 3.9(4) states this test will be conducted following cold shutdown and prior to raising the reactor coolant above 300*F.
This requirement is being clarified consistent with the recommendation of NUREG-0635 to be extended cold shutdowns, and NUREG 1432 (CE Improved Standard TS) which states that an extended cold shutdown is one longer than 30 days in duration.
Therefore, it is proposed that the surveillance be performed if-the unit has been in Mode 4 and/or 5 for more than 30 days (whenever the reactor coolant temperature is below 210 F for a total of more than 30 days).
PROPOSED CHANGES RELATED TO AFW VALVE TESTING lt is proposed to clarify TS 3.9(1) to state that following AFW system maintenance, only the valves affected by the maintenance are checked for proper alignment.
The AFW system valves not being maintained are already in the proper alignment as verified by the monthly alignment check.
It is proposed to revise TS 3.9(3) to delete reference to testing the AFW regulating valves at least every three months to state that testing will be in accordance with the IST Program.
The IST Program is controlled by TS 3.3 and requires these valves to be tested quarterly and therefore, there is no change in the frequency of testing.
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DISCUSSION AND JUSTIFICATION (Continued):
BASIS SECTION in addition to the clarifications to describe the different flow paths that must be tested and clarifications to incorporate the proposed changes to the surveillances, the Basis Section is being reorganized and surveillance numbers are being added to coincide with the order of the surveillances.
A more complete description of the safety related function of the AFW system is proposed for addition to the Basis Section.
Clarification is being added to the Basis of TS 3.9(1) to state that following AFW system maintenance, only those valves affected by the maintenance are verified to be in the correct position.
l Clarification is being added to the surveillance of the AFW regulating valves description to state that testing is in accordance with the Inservice Testing Program and to delete the description of confirming a flow path.
The flow path is verified by TS 3.9(4). TS 3.9(3) only verifies operability of the valves and not the flow path.
Clarification is also being added to state that the testing conducted by TS 3.9(5) for the automatic AFW initiation is accomplished by utilizing overlapping tests that verify the instrumentation valves and motor driven pump are operable with the steam turbine driven pump tested separately to verify its operability.
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BASIS FOR NO SIGNIFICANT HAZARDS CONSIDERATION:
The proposed changes do not involve significant hazards consideration because operation of Fort Calhoun Station (FCS) Unit No. 1 in accordance with these chaages would not-4 (1)
Involve a significant increase in the probaoility or consequences of an accident previously evaluated.
A change to Technical Specification (TS) 3.9(2) is proposed to delete the specific discharge pressure specified for the Auxiliary Feedwater (AFW) pumps' surveillance.
The developed head of the motor driven and steam turbine-driven AFW pumps is verified quarterly.
These tests are in addition to those required by TS 3.3 which implements ASME Section XI Inservice Testing (IST) to evaluate a pump's performance against its pump curve to determine operability.
The IST program is controlled by TS 3.3, and requires that testing of /SME Code Class 1. Class 2 and Class 3 pumps shall be performed in accordance with Section XI of the ASME Boiler and Pressure Vessel Code, as required by 10 CFR 50.55a(g).
except where specific written relief has been granted by the NRC.
Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.
The proposed changes to TS 3.9(4) and the Basis Section only clarify the AFW flow paths that are required to be tested.
The proposed change follows the recommendations of NUREG 0635. " Generic Evaluation of Feedwater Transients and Small Break Loss-of-Coolant Accidents in Combustion Engineering Designed Operating Plants,' Recommendation GS-6(2).
No physical changes are proposed, information is being added to clarify the testing required to meet the recommendations of NUREG-0635.
therefore these proposed changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.
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4 BASIS FOR NO SIGNIFICANT HAZARDS CONSIDERATION (Continued):
(2)
Create the possibility of a new or different kind of accident from any accident previously evaluated.
There will be no physical alterations to the plant configuration or changes in operating modes.
The proposed change to delete the specific discharge pressure of the AFW pumps from the TS is consistent with the ASME Code Section XI requirements that are controlled by TS 3.3.
Testing requirements of TS 3.3 requires testing of ASME Code Class 1.
Class 2, and Class 3 pumps in accordance with Section XI of the ASME Boiler and Pressure Vessel Code, as required by 10 CFR 50.55a(g). except where specific written relief has been granted by the NRC.
The clarifications being provided to describe the flow paths only provides addition information for testing required to meet the recommendation of NUREG-0635.
Therefore, the proposed changes do not create the possibility cf a new or different kind of accident from any previously evaluated.
(3)
Involve a significant reduction in a margin of safety.
l The proposed changes will not result in any physical alterations to the plant configuration or changes to the application of setpoints or limits.
Therefore, the proposed change does not involve a significant reduction in a margin of safety.
Therefore based on the above considerations it is OPPD's position that this proposed amendment does not involve significant hazards considerations as defined by 10 CFR 50.92 and the proposed changes will not result in a condition which significantly alters the impact of the Station on the environment.
Thus, the proposed changes meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9) and pursuant to 10 CFR 51.22(b) no environmental assessment need be prepared.
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