ML20056H409
| ML20056H409 | |
| Person / Time | |
|---|---|
| Site: | Duane Arnold  |
| Issue date: | 04/14/1993 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20056H405 | List: |
| References | |
| NUDOCS 9309090278 | |
| Download: ML20056H409 (17) | |
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UNITED STATES
[
j NUCLEAR REGULATORY COMMISSION WASHINGTON. D.C. 20556-0001
%.~....]
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION
{
RELATED TO AMENDMENT NO.193 TO FACILITY OPERATING LICENSE NO. DPR-49 IOWA ELECTRIC LIGHT AND POWER COMPANY CENTRAL IOWA POWER COOPERATIVE CORN BELT POWER COOPERATIVE l
DUANE ARNOLD ENERGY CENTER DOCKET NO. 50-331 l
L l.0 INTRODUCTION In a letter dated Decwber 19, 1991 and supplemented by additional information f
on August 25, October 8, and November 24, 1992, and March 8, 1993, Iowa i
Electric Light and Power Company (IELP), the licensee, proposed changes to the i
l Technical Specifications (TS) for the Duane Arnold Energy Center (DAEC).
The proposed TS changes: 1) incorporate the extended surveillance test intervals (STIs) and allowable out-of-service times (A0Ts) for Reactor Protection System (RPS) Instrumentation, Isolation Actuation Instrumentation, Emergency Core i
Cooling Systems (ECCS) Actuation Instrumentation, and Control Rod Block function Instrumentation, in accordance with NRC-approved Licensing Topical Reports (LTRs) previously. submitted by the Boiling Water Reactor Owners Group l
(BWROG), of which IELP is a member; 2) revise Sections 3.1 and 3.2 to improve clarity and provide consistency with the NRC Standard Technical Specifications (NUREG-0123); 3) incorporate Operating Modes into the Technical Specifications (TS) requirements for instrumentation; and 4) make editorial changes to TS l
Sections 3.1 and 3.2 to correct errors and for consistency with STS and the other changes in this amendment. This safety evaluation verifies that the TS changes proposed by the licensee in item 1) above and their associated justifications are bounded by the analyses provided in the approved topical reports and that any plant-specific issues are adequately addressed.
For items 2) through 4), this safety evaluation verifies that the licensee provided adequate justification that the proposed changes are acceptable.
l j
2.0 EVALUATIONS For the changes made in accordance with LTRs, the licensee's proposal is divided into four separate packages: (1) Reactor Protection System (RPS)
Instrumentation; (2) Isolation Actuation Instrumentation; (3) Emergency Core l
Cooling System (ECCS) Actuation Instrumentation; and (4) Control Rod Block
-Function Instrumentation. The staff evaluation is divided in'the same manner
- below, i
The editorial changes to other sections are addressed separately in subsequent paragraphs.
5 9309090278 930814 ~
PDR ADOCK 05000331 P
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. 2.1 REACTOR PROTECTION SYSTEM (RPS)
On July 15, 1987, the staff forwarded its safety evaluation report (SER) on the review of the following General Electric (GE) Licensing Topical Reports (LTRs):
(1) NEDC 30844, "BWR Owners Group Response to NRC Generic Letter 83-28," and (2) NEDC 30851-P, " Technical Specification Improvement Analysis for BWR RPS."
NEDC 30844 forwarded the BWR0G's technical basis that current BWR RPS surveillance test intervals (STIs) meet the recommendations of GL 83-28, Item 4.5.3.
NEDC 30851-P utilized the base case results of NEDC 30844 and fault tree modeling to establish a basis for extending the current RPS STIs and allowable out-of-service times (A0Ts).
The staff's review of the above-mentioned LTRs concluded that GE used a valid procedure to determine that there would be no significant increase of RPS failure frequency for the relay RPS BWR plants that were reviewed, and that the proposed changes in the TS for the relay RPS are generally acceptable.
l 2.1.1 CONDITIONS TO CLOSEOUT PLANTS The staff's Safety Evaluation (SE) is presented in a letter from Mr. A.
Thadani, NRC, to Mr. T. Pickens, BWROG, dated July 15, 1987. To implement the extended STIs and A0Ts for the RPS, the SE requires the licensee to do the following:
Confirm the applicability of the generic analyses of NEDC 30851-P to its plant.
Demonstrate, through the use of actual instrument drift information from the equipment vendor or from plant-specific data, that the drift characteristics for instrumentation used in the RPS channels in the plant are bounded by the assumptions used in NEDC 30851-P when the functional test interval is extended from monthly to quarterly.
Confirm that the differences between the RPS in the plant and the RPS of the generic analysis plant were included in the plant-specific analysis using the procedures of Appendix K of NEDC 30851-P (and the results presented in
' to letter 0G5-491-12 from L. Rash (GE) to T. Collins (NRC) dated November 25,1985), or provide plant-specific analyses to demonstrate that there is no appreciable change in RPS availability or public risk.
2.1.1.1 APPLICABILITY OF NEDC 30851-P-A: The Duane Arnold Energy Center j
(DAEC) is a BWR-4 relay reactor protection system facility. The licensee, in a sworn application, confirmed the applicability of the generic analysis for NEDC 30851-P-A to the DAEC.
i 2.1.1.2 INSTRUMENT DRIFT ANALYSIS:
Instrument setpoint drift is monitored during channel calibration tests when setpoints are required to be verified and/or set, not during the performance of the channel functional tests. However, for the sake of expediency, many licensees find it more efficient to also monitor setpoints in conjunction with the channel functional test.
For plants whose
l 8
h current TS require channel calibration tests at shorter intervals than the proposed quarterly interval for channel functional tests, a concern therefore exists because in these cases, when the extension of the channel functional test interval to quarterly was proposed, a change was also requested to extend the channel calibration interval.
This change in channel calibration interval would then require a consideration of the effects n setpoint drift. At DAEC, however, the channel calibratio.. intervals for the RPS instrumentation are already equal to or greater than quarterly.
Since the channel calibration intervals are not affected by the proposed changes, instrument drift is not a factor l
and the RPS channel setpoint drift that could be expected under r
the proposed quarterly STIs for the channel functional test will remain within the existing allowance in the RPS instrument setpoint calculation.
2.1.1.3 PLANT SPECIFIC ANALYSIS:
A plant-specific analysis for the DAEC was performed that utilized the procedures of NEDC-30851-P-A, Appendix K to identify and evaluate the differences between the parts of the RPS that perform the trip functions at the DAEC and those of the base case plant.
In a sworn application, the l
licensee confirmed that the differences that were found do not significantly affect the improvement in plant safety achieved in 1
tha generic analysis, and, therefore, the results of LTR NEDC-l 30851-P-A are applicable and the DAEC is bounded by the generic j
analysis and the corresponding NRC staff SE.
Based on the above, the findings of NEDC-30851-P-A and the conclusions of the NRC staff's July 15, 1987 SE are applicable to the Duane Arnold Energy Center.
l 2.1.2 Allowable Out-of-Service Times (A0Ts) 2.1.2.1 Discussion:
Trip functions which initiate RPS trips include (a) 1RM neutron flux, (b) APRM flow-referenced neutron flux, (c) reactor vessel steam dome pressure - high, (d) reactor water level - low, (e) main steam line isolation valve - closure, (f) main steam line radiation - high, (g) drywell pressure - high, (h) scram discharge volume water level - high, (1) turbine stop valve - closure, (j) turbine control valve fast closure, valve l
trip system oil pressure - low, (k) turbine first stage pressure l
permissive, (1) reactor mode switch shutdown position, and (m) manual scram. Trip level settings, applicable operating modes, i
minimum number of operable channels per trip system, and actions, are identified in TS 3.1.A and associated Table 3.1-1.
These TS require that, if fewer than the minimum operable channels per trip system (serving a trip function) are found or made inoperable, that trip system and/or the inoperable channel (s) must be placed in a tripped condition or the facility placed in a condition for l
which the trip function is not required.
The proposed amendment l
would change the TS to allow a 12-hour delay before placing thE s -,
a w
- ---- - ~,
{ inoperable channel and/or that trip system in a tripped condition when there is only one inoperable channel in a trip function.
In addition, an instrument channel would be permitted to be made inoperable for up to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> for required surveillance testing i
without placing the trip system in the tripped condition provided there remains at least one operable channel in the same trip i
system for that trip function.
Additional changes are also being proposed to the Table Notations for Table 3.1-1 to be consistent with the technical and format i
changes to the Table. These changes incorporate the format of the standard technical specifications while retaining the " Trip Level Setting" column in its current format tc lessen the impact the revisions have on the operators. The " Applicable Operating Modes" i
were revised to reflect the new definitions of the various Operating Modes that were added by Table 1.0-1.
The orientation of Table 3.1-2 was physically changed by rotating it on the page to be consistent with the other tables in Section 3.1.
The Table was also placed behind the actions and table j
notations for Table 3.1-1 to enhance the continuity of the section.
i 2.1.2.2 Evaluation:
The proposed changes are consistent with paragraph 5.8 of the SE issued July 18, 1987, which found that for applicable facilities, A0Ts for the repair or surveillance testing of a single instrument channel of up 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, respectively, would have a negligible impact on RPS failure frequency and could decrease operator error and decrease the I
likelihood of an inadvertent scram.
In addition, the proposed i
terminology precludes the possibility of misinterpretation of i
actions required in the event that more than one required channel j
is inoperable in the same trip system (
Reference:
C. Rossi (NRC) letter to G. Beck (BWROG) dated July 26,1991).
Accordingly, i
these proposed changes are acceptable.
The changes proposed to the Table Notations for Table 3.1-1 are consistent with the changes made to the Table itself and are, I
therefore, acceptable. The use of the Operating Modes is j
consistent with Table 1.0-1 and is, therefore, acceptable.
The change in the physical orientation and location of Table 3.1-2 is of format only, and does not change any technical information and is acceptable.
2.1.3 Surveillance Test Intervals (STIs) 2.1.3.1 Discussion: Table 4.1-1 presently specifies an STI for the channel functional tests of "Once per week" for the following RPS instrumentation channels:
- 1) APRM neutron flux - upscale, 2) APRM neutron flux - inoperative, and 3) Main Steam Line Radiation -
High.
For the following RPS instrumentation channels, the
~
L.
frequency is specified as "Every 1 month":
- 1) Reactor Vessel Steam Dome Pressure - High, 2) Reactor Water Level - Low, 3) Main Steam Line Isolation Valve - Closure, 4) Drywell Pressure - High,
- 5) Turbine Stop Valve - Closure, and 6) Turbine Control Valve Fast Closure, Valve Trip System Oil Pressure - Low.
The proposed amendment would change the Table 4.1-1 STIs for the channel functional test to quarterly for all these RPS instrumentatiun channels.
In addition, consistent with the LTR, the functional test interval for Manual Scram would be changed from "Every 3 months" to weekly.
The proposed amendment would also delete the surveillance requirements for the Reactor Pressure Permissive function, which refers to a permissive signal that enabled the MSIV closure scram. This permissive signal is not active at the DAEC, hence, this surveillance test requirement is not applicable.
The APRM Neutron Flux - Upscale in Startup calibration requirement is not currently specified. The proposed amendment would establish a semiannual channel calibration for this trip function, which is consistent with other DAEC calibration intervals.
The surveil-lance requirement currently listed as APRM - Flow Bias has been incorporated into the APRM Neutron Flux - Upscale requirements.
Additional changes also were proposed to the Table Notations for Table 4.1-1 to be consistent with the technical and format changes to the Table.
Tables 4.1-1 and 4.1-2 were combined into one table, and, in so doing, the licensee deleted notes from Table 4.1-2 that are no longer applicable or are redundant. All notes that still apply are in Table 4.1-1.
2.1.3.2 Evaluation: The revision of STIs as described above is consistent with the July 15, 1987 SE and is, therefore, acceptable.
Deletion of the surveillance requ rements for the Reactor Pressure Permissive i
function is acceptable since the permissive signal is not active at the DAEC.
The addition of the APRM Neutron Flux - Upscale in Startup semiannual calibration requirement is consistent with other DAEC calibration intervals and is acceptable.
Incorporation of the sur-veillance requirement currently listed as APRM - Flow Bias into the APRM Neutron Flux - Upscale requirements is also acceptable. The LTR determined that operator error disabling all scram contactors was the primary contributor to the RPS failure frequency. Under the proposed TS requirements, channel functional testing of the manual scram on a weekly instead of quarterly basis by actuating the channel manual scram / test switches in the control room will be performed.
The weekly testing of manual scram is an efficient way of detecting the common cause failures of scram contactors due to operator error and will maintain overall RPS availability and is acceptable.
I 1
1 i
! The changes to the notes for the former Tables 4.1-1 and 4.1-2 involve the deletion of notes that no longer apply and others that are reformatted and contained in the new Table 4.1-1.
The technical changes are consistent with changes to the A0Ts, STIs and the addition i
of Operating Modes and are therefore acceptable. The changes in l
format are editorial in nature and do not affect the requirements for minimum number of operable channels, A0Ts, or STis. On this basis, these changes are acceptable.
2.1.4 Excessive testina 2.1.4.1 Discussion:
TS Section 4.1.A.3 carrently requires that if, it is i
determined that an instrument channel has failed in the unsafe condi-l tion, the other RPS instrument channels that monitor the same variable
(
shall be functionally tested immediately, before the trip system con-taining the failure is tripped.
The licensee has proposed deleting this requirement.
1 2.1.4.2 Evaluation:
Requiring immediate testing of the other instrument j
channels is contrary to the topical report in that the additional i
j testing increases the potential for human error that could cause a l
reactor trip and a subsequent plant transient.
The requirement to perform immediate testing essentially places an allowable out-of-service time of zero on the failed instrument, increasing the stress l
of the testing, and, consequently, increasing the likelihood of l
operator error.
In Section 5.8 of the SE, the staff concluded that the allowable out-of-service time for testing of individual instrument channels could be extended to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. Deletion of the requirement to perform immediate testing is consistent with this conclusion.
for the above-mentioned reasons, deletion of the requirement to immediately functionally test the other RPS instrument channels that monitor the same variable, if it is determined that an instrument channel has failed in the unsafe condition, is acceptable.
2.1.5 Group Desianations - Table 4.1 Functional Test Frecuencies 2.1.5.1 Discussion:
TS Table 4.1-1 presently contains a column for group identification of each listed instrument as to whether it is an "A" on-off sensor, a "B" analog device coupled with bi-stable trips, or a "C" device which only serves a function during a restricted mode of operation or one for which the only practical test can be performed at shutdown.
In addition, the table contains a column titled " Functional Test" that briefly describes the method of performing the functional test.
The licensee proposes to delete these two columns of descriptive information from the table.
2.1.5.2 Evaluation:
The group identification information and the verbal descriptions of the functional test methods which the licensee l
proposes to delete are descriptive in nature. The group l
I f
! identification information also relates to information presented in the Bases section.
Elimination of the above information from the table would not affect the requirements for minimum number of operable i
channels, A0Ts, or STIs.
Such information is not typically included i
and serves no useful purpose in TS tables defining STI requirements.
1 On this basis, deletion of the above descriptive information from TS 1
Table 4.1-1 is acceptable.
i 2.1.6 Group Desionations - Table 4.1 Calibration Test Frecuencies t
l 2.1.6.1 Discussion: TS Table 4.1-2 presently contains a column for group identification of each listed instrument as to whether it is an "A" on-off sensor, "B" analog device coupled with bi-stable trips, or a "C" device which only serves a function during a restricted mode of operation or one for which the only practical test can be performed at shutdown.
In addition, the table contains a column titled "Cali-bration" that briefly describes the method of performing the calibra-tion test. The licensee proposes to delete these two columns of descriptive information from the table.
t 2.1.6.2 Evaluatien:
The group identification information and the verbal descriptions of the calibration test methcds which the licensee proposes to delete are descriptive in nature. The group identif-ication information also relates to information presented in the Bases section.
Elimination of the above information from the table would not affect the requirements for minimum number of operable channels, A0Ts, or STIs. Such information is not typically included and serves i
no useful purpose in TS tables defining STI requirements. On this i
basis, deletion of the above descriptive information from TS Table 4.1-2 is acceptable.
i 2.1.7 Chances Common to Tables 4.1-1 and 4.1-2 2.1.7.1 Discussion:
The proposed change combines TS Tables 4.1-1 and 4.1-2 into a single table. The trip functions addressed have been changed in certain instances to be consistent with the changes in content of Table 3.1-1.
Applicable Operating Modes have been incorporated, consistent with new Table 1.0-1.
Channel check requirements for all instruments have been added, consistent with the staff's SE and the LTR.
l 2.1.7.2 Evaluation: The addition and changes of these requirements is i
conservative and provides consistency with the requirements of other instrumentation in the TS and is acceptable.
2.1.8 Reformattino 2.1.8.1 Discussion: The proposed amendment reformats the Limiting Conditions for Operation (LCOs) and Surveillance Requirements (SRs) for Sections 3.1.A and 4.1.A to use a format similar to the Standard Technical Specifications.
I i
} 2.1.8.2 Evaluation:
The changes associated with reformatting the sections are editorial in nature and are acceptable.
2.2 ISOLATION ACTUATION INSTRUMENTATION 2.2.1 Apolicability of Licensino Topical Reports The proposed changes are based on NEDC-30851-P-A, Supplement 2, " Technical Specification Improvement Analysis for BWR Isolation Instrumentation Common to RPS and ECCS Instrumentation," and NEDC-31677-P-A " Technical Specifi-cation improvement Analysis for BWR Isolation Actuation Instrumentation."
SEs for these topical reports were issued on January 6, 1989, and June 18, 1990, respectively.
These SEs state that individual plants must:
1)
Confirm applicability of the generic analyses to the plant, and 2)
Confirm that any increase in instrument drift due to the extended STIs is properly accounted for in the setpoint methodology.
The licer.see confirmed 1) above in its application.
Regarding 2) above, (instrument drift) the same argument used in Section 2.1.1.2 applies.
Based on the above, the findings of NEDC-30851-P-A, Supplement 2, and NEDC-31677-P-A, and the conclusions of the staff's January 6, 1989, and June 18, 1990, SEs, respectively, are applicable to the Duane Arnold Energy Center.
2.2.2 Allowable Out-of-Service Times (A0Ts) 2.2.2.1 Discussion:
TS 3.2. A, in conjunction with Table 3.2-A, specifies total and minimum number of operable instrument channels per trip system, the trip level setting, number of instrument channels provided by design, valve groups operated by signal, and the applicable action.
The action statements are contained in the Notes for Table 3.2-A, and state the A0Ts for the instruments whose actuation signals isolate the following groups of valves:
(1)
Main Steam, Drains, and Recirculation Sample Isolation Valves (2)
Radwaste Isolation Valves (3)
Containment Atmosphere Isolation Cooling Valves (4)
Residual Heat Removal Shutdown Cooling Isolation Valves (5)
Residual Heat Removal Low Pressure Coolant Injection Isolation Valves (6)
Reactor Water Cleanup Isolation Valves (7)
Reactor Core Isolation Cooling (RCIC) Isolation Valves (8)
High Pressure Coolant Injection (HPCI) Isolation Valves (9)
Reactor Building Closed Cooling Water and Well Water Containment Cooling Isolation Valves (10)
Reactor Core Isolation Cooling and High Pressure Coolant Injection Condensate Return Isolation Valves
_g.
l (11) Reactor Core Isolation Cooling and High Pressure Coolant Injection Vacuum Breaker Line Isolation Valves The proposed amendment applies to groups (1), (2), (3), (4), (5), (8),
(9), and manual initiation of isolation for HPCI and RCIC.
Instruments or switches serving these groups or functions include the following:
(A)
Reactor Water Level - Low (B)
Drywell Pressure - High (C)
Reactor Water Level - Low-tow-Low (D)
Main Steam Line Radiation - High (E)
Main Steam Line Pressure - Low (F)
Main Steam Line Flow - High (G)
Condenser Backpressure - High (H)
Main Steam Line Tunnel Temperature - High (I)
Turbine Building Temperature - High (J)
Refuel Floor Exhaust Duct - High Radiation (K)
Reactor Building Exhaust Shaft - High Radiation s
(L)
Offgas Vent Stack - High Radiation (M)
Manual Initiation of RCIC Isolation (N)
Manual Initiation of HPCI Isolation The present TS requires that if the Minimum Number of Operable Instrument Channels per Trip System cannot be met for one of the trip systems, that trip system shall be placed in the tripped conditicA, or the appropriate action taken.
The proposed amendment would allow continued operation without placing an instrument system in the tripped condition, for up to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> if the Minimum Operable Channels per Trip System cannot be met.
It would also allow a channel to be placed in an inoperable status for up to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> for required surveillance testing without placing the trip system in the tripped condition provided at least one operable channel in the same trip system is monitoring that parameter.
2.2.2.2 Evaluation:
For instruments (A) and (B) above, the proposed changes I
are within the scope of NEDC 31677-P-A and the staff's June 18, 1990 i
SE. The proposed changes for instruments (C) through (N) above are within the scope of NEDC-30851-P-A and the staff's January 6,1989 SE.
The changes are acceptable on the basis of the conclusions reported in those SEs.
2.2.3 Surveillance Test Intervals (STIs) 2.2.3.1 Discussion:
STIs for functional tests of isolation instrumentation are contained in TS 4.2.A.
Table 4.2-A presently specifies an STI of monthly for the channel functional test of the following instruments:
1)
All common isolation signals 2)
All Main Steam Line Isolation Signals 3)
Reactor Vessel Pressure - High
4)
All Reactor Water Cleanup Signals Ta.
4.2-B presently specifies an STI of monthly for the channel t
functional test of the following instruments:
I)
HPCI and RCIC Isolation on Steam Line Differential Pressure (Flow) - High 2)
HPCI and RCIC Isolation on Equipment Room Temperature - High, Room Ventilation Differential Temperature - High, Suppression Pool Area Temperature - High, Suppression Pool Area Ventilation Differential Temperature - High 3)
HPCI and RCIC Isolation on Steam Supply Pressure - Low The proposed amendment extends the channel functional test interval for these instruments to quarterly.
The HPCI and RCIC requirements formerly contained in Table 4.2-8 have been moved to Table 4.2-A for consistency.
The channel functional test STI for RCIC and HPCI Turbine Exhaust Diaphragm Pressure - High and RCIC and HPCI Manual Initiation are not presently addressed in the TS.
They have been added to TLble 4.2-A with a monthly STI.
The channel functional test of Standby Liquid Control System Initiation is not presently addressed in the TS and is being added by the proposed amendment.
It is being assigned an STI of once every operating cycle since the performance of this functional test will cause the isolation of the RWCU system.
Table 4.2-A presently contains a requirement for a channel functional test of Reactor low-Low Water Level. The isolation function that actually occurs is due to HPCI or RCIC system initiation in that when HPCI or RCIC is initiated its steam supply valve starts to open.
This valve not being fully closed causes an isolation of the HPCI or RCIC condensate return line valves. For the purpose of clarification, the Reactor Low-Low Water Level entry in the present Table 4.2-A is being reworded as HPCI or RCIC System Initiation. These trip functions are being assigned channel functional test intervals of once per operating cycle, to be consistent with similar trips initiated by valve position limit switches and with the Manual Initiation, which also requires the cycling of the steam supply valves.
The proposed amendment relocates the Logic System Functional Tests presently contained in Table 4.2-A to TS Section 4.2.A.2 but does not change any technical requirements.
Requirements for HPCI and RCIC Leak Detection Time Delay are presently addressed in Table 4.2-B by the single line item Auto Sequencing Timers.
For the purpose of clarity, this line item has been split into two separate items as HPCI and RCIC Leak Detection Time Delay and added to Table 4.2-A.
The channel functional test and calibration i
' intervals are assigned consistent with the STS and the requirements of similar trip functions for room temperature and ventilation differential temperature.
Consistent with Table 1.0-1, Operating Modes have been added to Table 4.2-A.
Changes have been made to the Notes of Table 4.2-A for consistency and clarification.
i The proposed note (#) for Main Steam Line Radiation - High # was removed because Amendment 182 eliminated the Reartor Protection System trip function and the Main Steam Line Isolation i,
an from the Main l
Steam Line Radiation Monitors.
i The remaining trip functions retain their current surveillance requirements.
2.2.3.2 Evaluation:
The proposed changes of STIs from monthly to quarterly are in accordance with the requirements of NEDC-30851-P-A, Supplement 2 or NEOC-31677-P-A and the staff's SEs of January 6, 1989, and 1
June 18, 1990, respectively, and are acceptable.
The remaining l
changes are either editorial in nature or consisteat with the STS, and are also acceptable, 2.3 CCRE AND CONTAINMENT COOLING SYSTEMS INITIATION / CONTROL INSTRUMENTATION 2.3.1 Applicability of Licensino Topical Reports On November 14, 1985, the BWROG submitted LTR NEDC-30936P, "BWR Owners' Group Technical Specification Improvement Methodology (with Demonstration for BWR ECCS Actuation Instrumentation), Part 1."
This LTR utilized a probabilistic risk assessment methodole;y for determining the impact due to l
The change in water injection unavailability was calculated by changing STI and A0T requirements one component at a time, the cnange being so small that the average unavailability with respect to time was ignored. A demonstration case, using a sample ECCS instrumentation STI and A0T, was analyzed for BWRs.
In addition, the LTR provided a set of guidelines for licensees on how to perform plant-specific evaluations of TS improvement analysis for STIs and A0Ts related to ECCS actuation instru-mentation.
The BWROG also committed to submitting additional analyses of the remaining ECCS actuation instrumentation as an addendum (Part 2) to NEDC-30936-P Part 1 of the TS improvement methodology.
Part 2 was to include evaluation of STIs and A0Ts for the remaining ECCS actuation instru-mentation, and plant-specific verification of the applicability of the generic results.
In an SE dated December 9,1988, the staff's SE concluded that the BWROG analyses demonstrated the acceptability of general methodology for con-t sidering TS changes to the ECCS instrumentation used in the BWR facilities.
i
. lt also identified a list of plant-specific issues which needed to be addressed by each licensee to make any proposed ECCS TS changes acceptable.
Od July 23, 1987, the BWROG submitted LTR NEDC-30936P, "BWR Owners' Group Technical Specification Improvement Methodology (with Demonstration for BWR ECCS Actuation Instrumentation) Part 2," for staff review. This LTR utilized fault tree methodology to estimate the impact of the proposed changes on the average water injection function failure frequency utilizing only the loss of Offsite Power (LOSP).
Different from Part 1, in the Part 2 LTR, changes to the STIs and A0Ts for all ECCS actuation instrumentation are l
proposed. The Part 2 LTR analyzes only the Loss of Offsite Power (LOSP) initiating event since most BWR FRA experience indicates that LOSP contributes from 40% to 90% of the overall core damage frequency. The selection of this event as sufficiently representative was approved by the staff in an earlier study.
In a letter to the BWROG dated December 9, 1988, the staff forwarded its SE on the GE Topical Report NEDC-30936P Part 2.
The staff's review of the LTR focused on the acceptability of the bases for extending the STIs from 31 days to 92 days, the A0T for surveillance from 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, i
and the A0T for repair from I bour to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
The staff approved the I
analytic methods and general conclusions of the LTR indicating that licensees must confirm the LTR applicability to the specific plant and ad-j dress instrument drift.
The changes of Part 2 encompass those of Part 1, so satisfaction of the plant-specific conditions of Part 2 meets the require-ments of Part 1.
Therefore, licensees were only required to address the requirements of Part 2.
s The plant-specific conditions that individual plants must meet to make any proposed STl or A0T changes fully acceptable are as follows:
1)
Confirm applicability of the generic analyses to the plant, and 2)
Confirm that any increase in instrument drift due to the extended STIs is properly accounted for in the setpoint methodology.
The licensee confirmed 1) above in its application.
Regarding 2) above, (instrument drift) the same argument used in Section 2.1.1.2 applies.
Based on the above, the findings of NEDC-30936-P-A, Parts 1 and 2, and the l
conclusions of the NRC staff's December 9,1988, SEs are applicable to the Duane Arnold Energy Center.
2.3.2 Allowable Out-of-service Times (A0Ts) 2.3.2.1 Discussion:
The licensee proposed the following changes to the A0Ts of the ECCS Actuation TS which have generally been reviewed and approved in the staff's SE dated December 9, 1988 for LTR NEDC-30936-P, Part 2.
t
. In the Notes of Table 3.2-B, Note (a) has been modified to reflect the extended A0T of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
In the Actions of Table 3.2-B, the extended A0Ts have been implemented in the action statements instead of the LCOs. This is in accordance with the guidance provided in letter OG090-319-32D, J. F. Klapproth (GE BWROG) to M. L. Wohl (h90), Clarification of Technical Specification Changes Given in ECCS Actuation Instrumentation Analysis, March 22, 1990.
2.3.2.2 Evaluation:
The above changes to Table 3.2-B are consistent with the conclusions of NEDC-30936-P-A, Part 2, and the staff's SE dated December 9, 1988, and are, therefore, acceptable.
2.3.3 Surveillance Test Intervals (STis) 2.3.3.1 Discussion:
The licensee proposed the following changes to the STIs of the ECCS Actuation TS which have generally been reviewed and ap-proved in the staff's SE dated December 9, 1988 for LTR NEDC-30936-P, Part 2:
The channel functional test intervals in Table 4.2-B were extended from monthly to quarterly for the following instruments.
1.
Reactor Water Level-Low-Low-Low 2.
Drywell Pressure - High 3.
Reactor Pressure - Low (Permissive) 4.
All HPCI initiation / control signals 5.
All RCIC initiation / control signals 6.
Reactor Water Level - Low (Confirmatory) (ADS) 7.
Core Spray Pump Discharge Pressure - High (Permissive) 8.
RHR (LPCI) Pump Discharge Pressure - High (Pernissive)
The surveillance requirements for the ADS timer are not clearly addressed in Table 4.2-B.
The channel functional test will be designated as quarterly, consistent with the LTR, and the calibration interval will be once per operating cycle consistent with the current DAEC test interval.
2.3.3.2 Evaluation:
The above changes to Table 4.2-B are consistent with the conclusions of NEDC-30936-P-A, Part 2, and the staff's SE dated December 9,1988, and are, therefore, acceptable.
2.3.4 Editorial Chances 2.3.4.1 Discussion: The licensee proposed additional changes to this TS and Tables 3.2-8 and 4.2-B that are editorial in nature.
They were made to be consistent with other changes to the TS, for consistency with the STS, or for clarity.
2.3.4.2 Evaluation: These changes are either not technical in nature, or
a
- approved by the staff or are being reviewed and approved by the staff in this amendment.
For these reasons, these additional editorial changes are acceptable.
2.4 CONTROL ROD BLOCK FUNCTION INSTRUMENTATION 2.4.1 Applicability of Licensino Topical Reports On June 23, 1986, the BWROG submitted LTR NEDC-30851P, Supplement 1, " Technical Specification improvement Analysis for BWR Control Rod Block Instrumentation." for t
NRC review.
The LTR provides a basis for extending the STI for control rod block function instrumentation. The control rod block function instrumentation shares common instrumentation with the RPS.
To gain the full safety benefit of the proposed RPS instrumentation TS changes, a corresponding STI extension for the control rod block function (CRBF) instrumentation is necessary.
Unlike the analyses discussed in Sections 2.1 and 2.3 above, no specific fault trees were developed for the control rod block function instrumentation.
- Instead, the impact on the average control rod block failure rate was estimated based upon the results in NEDC-30851P-A.
NEDC-30851P concluded that the benefits associated with the proposed changes to the RPS instrumentation TS offset any potential negative impact of extending the control rod block function instrumentation surveillance intervals.
In a letter dated September 22, 1988, the staff forwarded its SE on NEDC-30851?,
Supplement 1.
The staff approved the analytic methods and general conclusions of the LTR, indicating that licensees must confirm the LTR applicability to the specific plant and address instrument drift.
Specifically, the SE states that individual plants must:
1)
Confirm applicability of the generic analyses to the plant, and 2)
Confirm that any increase in instrument drift due to the extended STIs is properly accounted for in the setpoint methodology.
The licensee confirmed 1) above in its application.
Regarding 2) above, (instrument drift) the same argument used in Section 2.1.1.2 applies.
Based on the above, the findings of NEDC-30851-P-A, Supplement 1, and the conclusions of the NRC staff's September 22, 1988, SE are applicable to the Duane Arnold Energy Center.
The licensee proposed the following.hanges to the CRBF instrumentation TS which have generally been reviewed and generically approved in the staff's SE dated September 22, 1988, on LTR NEDC-30851-P-A, Supplement 1:
2.4.2 Surveillance Test Intervals 2.4.2.1 Discussion: The channel functional test STI specified in TS Table 4.2-C, " Control Rod Block Instrumentation Surveillance Requirements,"
is increased from monthly (M) to quarterly (Q) for all Rod Block e
Monitor and APRM trip functions.
In addition, the following instru-ments have been added to the table and will use STIs consistent with STS and include the extensions for the channel functional test ETI allowed by the staff's SE:
(I)
RBM Inoperative (2)
APRM Inoperative (3)
IRM Inoperative (4)
SRM Inoperative (5)
Recirculatior Flow Upscale Inoperative Comparator The SRM Downscale trip function will use a channel functional test STI consistent with existing SRM and IRM trip functions.
2.4.2.2 Evaluation:
The proposed changes to the STIs are in accordance with the staff's SE for the LTR, and are, therefore, acceptable.
2.4.3 Editorial Chanaes 2.4.3.1 Discussion: The licensee has proposed changes to TS Sections 3.2.C and 4.2.C and Tables 3.2-C and 4.2-C that are editorial, for clarification, to be consistent with the STS, to be consistent with other changes in this amendment, or to incorporate the use of Operating Modes.
The proposed change referenced Specification 3.2.C.2.a under Action 40.
Since this amendment request Amendment 180 was issued changing the referenced to 3.3.C.3.
2.4.3.2 Evaluation:
These changes do not alter the technical content of the TS requirements and are, therefore, acceptable.
2.5 Radiation Monitorino Instrumentation 2.5.1 Editorial Chanaes i
2.5.1.1 Discussion:
The licensee has proposed changes to TS Sections 3.2.0 and 4.2.0 and Tables 3.2-D and 4.2-D that are editorial, for clarification, to be consistent with the STS, to be consistent with j
other changes in this amendment, or to incorporate the use of Operating Modes.
a 2.5.1.2 Evaluation: These changes do not alter the technical content of the TS requirements and, therefore, are acceptable.
l 2.6 Drywell Leak Detection Instrumentation il
+
! 2.6.1 Editorial Chances 2.6.1.1 Discussion:
The licensee has proposed changes to TS Sections 3.2.E and 4.2.E and Tables 3.2-E and 4.2-E that are editorial, for clarification, to be consistent with the STS, to be consistent with other changes in this amendment, or to incorporate the use of Operating Modes.
2.6.1.2 Evaluation:
These changes do not alter the technical content of the TS requirements and, therefore, are acceptable.
2.7 Surveillance Instrumentation 2.7.1 Editorial Chances 2.7.1.1 Discussion:
The licensee has proposed changes to TS Sections 3.2.F and 4.2.F and Tables 3.2-F and 4.2-F that are editorial, for clarification, to be consistent with the STS, to be consistent with other changes in this amendment, or to incorporate the use of Operating Modes.
2.7.1.2 Evaluation: These changes do not alter the technical content of the TS requirements and are, therefore, acceptable.
2.8 Recirculation Pump Trio (RPT) and Alternate Rod Insertion (ARI)
Instrumentation l
2.8.1 Editorial Chances 2.8.1.1 Discussion:
The licensee has proposed changes to TS Sections 3.2.G and 4.2.G and Tables 3.2-G and 4.2-G that are editorial, for clarification, to be consistent with the STS, to be consistent with other changes in this amendment, or to incorporate the use of Operating Modes.
2.8.1.2 Evaluation:
These changes do not alter the technical content of the l
TS requirements and are, therefore, acceptable.
2.9 Accident Monitorina Instrumentation i
2.9.1 Editorial Chanaes 2.9.1.1 Discussion: The licensee has proposed changes to TS Sections 3.2.H and 4.2.H and Tables 3.2-H and 4.2-H that are editorial, for clarification, to be consistent with the STS, to be consistent with other changes in this amendment, or to incorporate the use of Operating Modes.
2.9.1.2 Evaluation:
These changes do not alter the technical content of the TS requirements and are, therefore, acceptable.
l
b t
I t -
2.10 Bases 2.10.1 Discussion:
The proposed amendment also includes changes to the Bases.
2.10.2 Evaluation:
Editorial changes have been made to the Bases to be consistent with the above changes, for clarity, for consistency with the STS, and to incorporate the use of Operating Modes. These changes do not alter the technical content of the TS Bases and are, therefore, acceptable.
2.11 Sucolemental Information i
The supplemental information in letters dated August 25, October 8, and November 24, 1992, and March 8, 1993 were either administrative or editorial in nature to clarify the original request and did not contain substantive changes to the original submittal.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations,.
.ppropriate Iowa State official was notified of the proposed issuance of the amendment.
The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
t This amendment changes requirements with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 or changes surveillance requirements.
The staff has determined that the amendment involves 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 proposed finding that the amendment involves no significant hazards consideration and there has been no public comment on such finding (57 FR 32573). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
5.0 CONCLUSION
l The staff 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) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of f
the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributors:
Clyde Y. Shiraki Date:
April 14,1993
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