ML20035E482
| ML20035E482 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 04/05/1993 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20035E478 | List: |
| References | |
| NUDOCS 9304160062 | |
| Download: ML20035E482 (31) | |
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'5, UNITED STATES 7.,
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NUCLEAR REGULATORY COMMISSION (Qiiigj I
WASWNGTON, D C. 20555 M 9'
p SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION
-j RELATED TO THE INSERVICE TESTING PROGRAM RELIEF RE00ESTS i
GEORGIA POWER COMPANY EDWIN 1. HATCH NUCLEAR PLANT. UNITS 1 AND 2 T
DOCKET NOS. 50-321 AND 50-366 j
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1.0 INTRODUCTION
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The Code of Federal Regulations,10 CFR 50.55a(f), requires that inservice f
testing (IST) of certain ASME Code Class 1, 2, and 3 pumps and valves be performed in accordance with Section XI of the ASME Boiler and Pressure Vessel i
Code and applicable addenda, except where specific written relief has been l
granted or an alternative has been authorized by the Commission pursuant to
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l Subsections (a)(3)(i), (a)(3)(ii), and (f)(6)(i) of 10 CFR 50.55a.
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requesting relief, the licensee must demonstrate that: (1) the proposed l
alternatives provide an acceptable level of quality and safety; (2) compliance
,2 would result in hardship or unusual difficulty without a compensating increase l
in the level of quality and safety; or (3) conformance with certain i
requirements of the applicable Code edition and addenda is impractical for its l
facility.
Generic Letter (GL) 89-04, " Guidance on Developing Acceptable l
Inservice Testing Programs," provides alternatives to Code requirements which i
have been determined by the staff to be acceptable, provided the alternatives are implemented in accordance with the guidance delineated in the applicable positions.
j Furthermore, in rulemaking to 10 CFR 50.55a effective September 8, 1992 (See l
57 Federal Reaister 34666), the 1989 edition of ASME Section XI was incorporated in paragraph (b) of 10 CFR 50.55a. The 1989 edition provides that the rules for IST of pumps and valves may meet the requirement + set forth in ASME Operations and Maintenance Standards Part 6 (OM-6), Inservice Testing of Pumps in Light-Water Reactor Power Plants, and Part 10 (OM-10), Inservice Testing of Valves in Light-Water Reactor Power Plants.
Pursuant to (f)(4)(iv), portions of editions or addenda may be used provided that all related requirements of the respective editions or addenda are met, and therefore, relief is not required for those inservice tests that are conducted in accordance with OM-6 and OM-10, or portions thereof. Whether all related requirements are met is subject to NRC inspection.
These regulations authorize the Commission to grant relief from or approve alternatives to the ASME Code requirements upon making the necessary findings.
The NRC staff's findings, with respect to approving the proposed alternative or granting or not granting the relief requested as part of the licensee's IST program, are contained in this safety evaluation (SE)..
The staff transmitted an Safety Evaluation (SE) to the licensee in a letter dated December 10, 1991.
This letter contained a Technical Evaluation Report 9304160062 930405 PDR ADOCK 05000321 P
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(TER) which addressed the licensee's second ten-year inservice testing i
program. Appendix A of the TER identified 29 anomalies which the licensee was i
requested to address within specified time periods. The licensee submitted a preliminary response to all the anomalies in a "HL-2142, Documents Verbal Agreement Between Util & NRR Re Technical Questions on Physical Installation of Containment Hardened Vent,Per Generic Ltr 89-16.Schematic of Proposed Torus [[Topic" contains a listed "[" character as part of the property label and has therefore been classified as invalid. Mod Encl|letter dated April 16, 1992]]. A i
4 response to 18 of the anomalies was submitted by the licensee in a letter
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dated June 5, 1992.
The responses are evaluated in this SE. By letter dated
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November 17, 1992, the licensee responded to the remaining anomalies, i
numbers 7, 10, 11, 13, 14, 15, 20, 22, 23, 24, and 26. These anomalies will j
be evaluated in a future SE.
l The licensee should address issues associated with relief requests that have i
been granted on a provisional or interim basis in this.SE within one year or.
i by the next refueling outage, whichever is later, unless otherwise specified in the SE. Testing associated with relief requests that have been denied is to be in compliance with applicable requirements within 90 days of the date of i
this SE.
I 2.0 RELIEF RE0 VESTS RELATED TO TER AN0MALIES l
2.0.1 General Comments The licensee stated in relief request RR-P-6, which is evaluated in Section 2.2 of this SE, that inservice testing of pumps will be conducted in j
accordance with the OM Code, 1990 Edition, Section ISTB.
The NRC has approved j-the use of ASME/ ANSI OMa-1988, Part 6 (OM-6), " Inservice Testing of Pumps in Light-W: iter Reactor Power Plants," for performance of inservice testing of i
pumps. The NRC has approved the use of OM-6 as alternative rules in lieu of l
Subsection IWP of Section XI through approval of Code Case N-465, " Alternative Rules for Pump Testing,Section XI, Divisicn 1."
The NRC's approval was j
provided in Regulatory Guide 1.147, " Inservice inspection Code Case Acceptability ASME Section XI Division 1," Revision 8, November, 1990, through r
footnote 6 of 10 CFR 50.55a.
In final rulemaking effective September 8,1992, published in the Federal Reaister, Volume 57, No. 152, Thursday, August 6, l
i-1992, the staff approved the 1989 Edition of ASME Section XI which references OM-6 as alternative rules for inservice testing of pumps.
Even though the Standard and the Code are similar, the licensee's use of the OM Code,_1990 g
Edition, is inappropriate. Therefore, the pump relief requests have been evaluated to the requirements of OM-6 rather than the OM Code, 1990 Edition.
The licensee should revise their IST program to reflect that their pump 3
testing will be performed in accordance with OM-6 which has been approved for use by NRC as alternative rules to IWP.
The licensee has stated in relief requests RR-P-6 and RR-P-7 (eva1uated in Sections 2.2 and 2.3 of this SE respectively) that the reactor core isolation 3
cooling system is not required to_be tested in accordance with ASME Section 1
XI. However, as stated in the response to question 53 in the meeting minutes on Generic Letter 89-04, for components important to safety, but not covered under Section XI of the ASME Code, the licensee has the obligation of i
demonstrating their continued operability. The Commission regulations do not require that relief requests for these components be submitted to the staff for evaluation, but documentation that provides assurance of the continued' l
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l l operability of the non-Code components should be available at the plant site for evaluation by NRC inspectors.
2.1 Relief Reauest RR-V-21 The licensee has requested relief from the full forward flow verification and reverse flow closure requirements of Section XI, Paragraph IWV-3520, for the 1
core spray pump minimum flow check valves E21-F036A & B and 2E21-F036A & B.
The licensee is proposing to disassemble and inspect one valve from each unit j
every refueling outage.
l 2.1.1 Licensee's Basis for Reauestino Relief j
The licensee states: "These valves are located in the core spray pump minimum flow lines discharging to the suppression pool. Valves must open to provide I
minimum flow protection for the core spray pumps and close to provide containment boundary.
Since there is no valve between the check valve and the suppression pool, the line cannot be pressurized to ensure closure of the j
valve. This valve is sealed from the primary containment atmosphere because the test line terminates below the water level of the torus and the leakage is not included in the Type C local leak rate testing."
i 2.1.2 Alternative Testino The licensee proposes: "Each valve is partial exercised open quarterly during j
core spray pump surveillance testing.
One valve for each unit will be disassembled, manually exercised and visually inspected each refueling outage per the guidance of GL 89-04. The valve internals will be confirmed as structurally sound (no loose or corroded parts) and the disk manually exercised to confirm full stroke capability.
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If the disassembled valve is not capable of being full stroke exercised or there is binding or failure of valve internals, the remaining valve will also
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be disassembled, inspected and manually full stroke exercised during the same outage.
1 There are no test connections provided to facilitate any measurements during j
pump testing. Therefore partial flow testing after re-assembly is not practical. The disassembled valve will be manually exercised just prior to re-installation of the cover flange to ensure stroke open capability."
2.1.3 Evaluation The core spray system at Hatch consists of two pumps, each drawing suction from the suppression chamber. The core spray pumps discharge into the reactor vessel through separate lines.
Each line has a test loop to facilitate flow testing of the core spray pumps. The pump minimum flow lines connect with their respective test loop lines and discharge back into the suppression chamber. The core spray pump minimum flow check valves are located between a i
. restricting orifice and the intertie to the test line. There are no test taps located between the minimum flow check valves and the suppression chamber.
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l The Code requires these valves to be exercised quarterly to the positions required to fulfill their safety function.
The core spray minimum flow check valves have a safety function in the open direction to allow water to flow through the minimum flow line and in the closed direction to prevent water from flowing out of the suppression chamber.
Closure verification of these valves is impractical because the system currently has no installed instrumentation which could facilitate testing.
l The licensee is proposing to partial-stroke exercise these valves quarterly and disassemble and inspect one valve from each unit every refueling outage in accordance with GL 89-04, Position 2.
The valves will be manually exercised prior to their return to service. Although GL 89-04 does provide guidance for the licensee to establish a disassembly and inspection program for valves that l
cannot be full-flow tested or tested for closure, Position 2 also states that partial valve stroking after reassembly must be performed if possible. The licensee states that partial flow testing after reassembly is not practical because there are no test taps in the system which provide pressure or flow I
data. However, no data acquisition is necessary in a partial-flow test. The i
objective of the testing is to verify that flow will pass through the valve.
Verification can be accomplished by simple means, such as observation of a l
temperature change in the pipe downstream of the check valve that is being
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tested.
l The post-inspection testing provides a degree of confidence that the disassembled valve has been reassembled properly and that the disk in the valve moves freely.
Disassembly and inspection is considered by the NRC to be a maintenance procedure with inherent risks which make its use as a routine substitute for Section XI testing undesirable when other testing methods are possible.
The licensee should actively pursue the use of non-intrusive diagnostic techniques to demonstrate that the disks in the valves full-stroke open during partial-flow testing.
If another method is developed to verify the full-stroke capability of these check valves, this relief should be revised or withdrawn.
Based on the determination that the Code requiremerts are impractical, and considering the licensee's proposed alternate testing, relief is granted, pursuant to 10 CFR 50.55a(f)(6)(i), provided that the licensee partial-stroke exercises the valves with flow after reassembly of the valve, if practical, even without direct process measurements.
The licensee should actively pursue the use of non-intrusive techniques to verify full-stroke opening and closure of these valves.
2.2 Relief Reauest RR-P-6 The licensee is requesting to conduct inservice testing for the pumps listed below in accordance with ASME OM Code-1990 in lieu of ASME Section XI, Subsection IWP. The licensee is also requesting relief from specific sections of the OM-1990 Code involving vibration testing.
Standby Liquid Control (SBLC)
Residual Heat Removal Service Water (RHRSW)
l i,I Core Spray (CS)
High Pressure Coolant Injection (HPCI)
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Reactor Core Isolation Cooling (RCIC)
Plant Service Water (PSW) 2.2.1 Licensee's Basis for Recuestino Relief i
The licensee states: "It has been recognized within the industry that the OM i
Code requirements for pump IST are more suitable than those of ASME XI IWP (Reference Code Case N-465)."
2.2.2 Alternative Testino The licensee proposes: "The testing requirements of the OM Code 1990, Section ISTB will be utilized for pump IST for those pumps required to be tested by ASME Section XI except as identified below."
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j Vibrational Points I
In lieu of the requirements of ISTB 4.6.4 (Note: licensee referenced ISTB 4.6.3 in June 5,1992, submittal) vibration measurements will be taken on each pump as outlined below.
a.
On centrifugal pumps measurements will be taken in a plane approximately perpendicular to the rotating shaft in two orthogonal directions.
These measurements shall be taken on each accessible pump bearing housing.
Measurements shall also be taken in the axial direction on each accessible pump thrust bearing housing.
If no pump bearing housings are accessible due to pump design or physical interference, then the measurements will be taken at the accessible location that gives the best indication of lateral / axial pump vibration.
This location is either on the pump casing, the motor bearing casing, or the motor casing.
b.
On vertical line shaft pumps measurements will be taken in a plane approximately perpendicular to the rotating shaft in two orthogonal directions in the area of the upper pump bearing housing. Thrust i
measurements will not be taken since measurements on top of the motor would be of limited benefit and would require installation of special ladders or scaffolding due to the height of the assembly for the RHR (Unit 1 only), Core Spray (Unit 1 only), RHRSW and PSW pumps.
Even with ladders or scaffolding, access is still limited due to interferences and personnel safety is of concern. The Standby Diesel Service Water Pump is equipped with a cooling fan in the top of the motor and a thin baffle plate prevents meaningful axial measurements.
It is recognized in the industry that the vibration testing of this type of pump has been of limited benefit for degradation detection due to the problems inherent with the design of the pumps.
The hydraulic testing requirements of the OM Code should provide adequate detection of pump degradation.
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On reciprocating pumps, a measurement will be taken on the bearing housing of the crankshaft, approximately perpendicular to both the crankshaft and the line of the plunger travel (As required by the OM Code).
Vibration Acceptance Criteria In lieu of the requirements of TABLE ISTB 5.2-2a, ranges for vibration acceptance criteria for smooth running pumps will be as outlined below.
Small absolute changes in vibration for smooth running pumps (e.g.,
s.075 in./sec.) would potentially result in Alert and Required Action Ranges being declared for exceeding the 2.5Vr or 6Vr limits even though the pump is operating satisfactorily.
The Alert Range for smooth running pumps will be > 0.19 to 0.45 in./sec.
and the Required Action Range starts at any value above 0.45 in./sec.
Frecuency Response Rance of Vibration Instrument In lieu of the requirements of ISTB 4.6.l(f), the vibration measuring instrument frequency response range will be as outlined below.
An I.R.D. Model 810 is utilized for IST vibration measurements.
This instrument has a frequency response range of 5.8 - 2,000 HZ for displacement measurement and 5.8 - 10,000 HZ velocity measurement.
The OM Code requires that the response range be one-third pump operating speed to at least 1000 Hertz. All pumps at Plant Hatch except the Standby Liquid Control (SBLC) Pump operate at 2 1150 RPM nominal, therefore, the frequency response range of the I.R.D Model 810 is acceptable.
The SBCL Pumps operate at 370 RPM (6.2 HZ), therefore, the vibration instrument frequency response range does not satisfy the code requirement for these pumps.
It would be impractical to require different types of vibration equipment for different pumps in the IST program from an implementation stand point.
Therefare, Plant Hatch proposes to utilize the existing equipment for vibration measurement on the Standby Liquid Control Pumps for consistency in the IST program.
These pumps are only placed in operation for required testing and therefore, see very little service, which would result in pump degradation.
In addition, the site maintenance department has the capability to perform spectral analysis with computerized equipment which would satisfy the frequency response range requirement of OM.
Therefore, if IST vibration measurements ever fall within the ALERT or ACTION P.ange, site maintenance department data will be utilized for evaluation of the operability / condition of these pumps.
The maintenance vibration analysis program was not developed to meet the same quality assurance
- - _. requirements as the IST program, however, past history has proven the program to be very effective in the monitoring and detection of vibration problems on rotating equipment at Plant Hatch.
2.2.3 Evaluation The licensee has stated that pump testing will be conducted in accordance with the OM Code, 1990 Edition.
The NRC has approved the use of ASME/ ANSI OMa-1988, Part 6 (OM-6), as alternative rules in lieu ef Subsection IWP of Section XI through approval of Code Case N-465, " Alternative Rules for Pump Testing.
Section XI, Division 1," and by rulemaking effective September 8, 1992.
Therefore, the exceptions to the requirements the licensee has described in this relief request will be evaluated in accordance with OH-6 (See Section 2.0.1 of this SE).
i Vibration Points The licensee is requesting relief to utilize the vibration measurement requirements of OM-6, Section 4.6.4(a), for all centrifugal pumps in the IST program.
The licensee's proposal is consistent with the Code requirements.
This relief request provides an acceptable level of quality and safety because the requirements are identical to the OM-6 requirements.
Therefore, the alternative is authorized, pursuant to 10 CFR 50.55a(a)(3)(1), as requested.
The licensee is requesting relief from the vibration measurement requirements of OM-6 Section 4.6.4(b), for certain vertical line shaft pumps in the IST program.
The Code requires measurements to be taken on the upper motor bearing housing in three orthogonal directions, one of which is the axial direction.
The licensee is requesting not to conduct axial vibration testing of the residual heat removal (RHR) and core spray pumps (unit 1 only), and the RHR service water, plant service water, and standby diesel service water (SDSW) pumps.
The staff is unaware of any relief requests of this type previously being submitted.
The staff understands the concerns raised by the licensee regarding safe access to components for the purposes of 131.
However, testing of this type on vertical line shaft pumps may be conducted safely by the use of ladders or scaffolding.
In addition, vibration testing on the motor bearing housing of vertical line shaft pumps is important because the design of the pump prevents access for taking thrust vibration data at any other location.
The ASME Operations and Maintenance Committee has recognized the importance of thrust vibration testing of vertical line shaft pumps by including these testing requirements in the 0Ma-1988 Code. The licensee has i
not pre:ented justification to address unique access problems that exist at
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Hatch with the exception of the SDSW pumps (see next paragraph).
Therefore, I
this relief request is denied and the licensee should either conduct axial vibration testing of these pumps in accordance with the Code or provide a revised relief request addressing specific access problems within 90 days.
The 50SW pump has a cooling fan mounted on top of the motor, limiting access to the bearing housing.
The design makes it is impractical for the licensee to measure axial vibration because access to the cooling fan is limited.
! However, alternate methods may exist.
For example, installation of permanent probes on the bearing housing with leads routed to a remote location may facilitate axial vibration measurement.
It would be a burden for the licensee to remove the cooling fan from the standby diesel pump mator each time to perform the Code-required testing. Requiring the licensee to meet the Code requirements immediately would also be a burden because a period of time is needed to investigate alternatin methods to measure axial vibration.
Therefore, interim relief is granted, pursuant to 10 CFR 50.55a(f)(6)(1), for a period of one year to allow the licensee to investigate methods to measure axial vibration of the SDSW pump bearing.
The licensee has also requested relief from the vibration requirements of OM-6, Section 4.6.4(c) pertaining to reciprocating pumps; however, the. licensee has pro;.osed alternate testing that is identical to the Code required testing.
Therefore, relief is not required.
Vibration Acceptance Criteria Relief from the vibration requirements of OM-6, Table 3a, for smooth. running pumps was granted in the TER transmitted to the licensee in a letter dated i
December 10, 1991. An evaluation of this portion of the relief request is not required in this SE.
Freauency Response Ranae of Vibration Instrument The licensee is requc :.ng relief from the vibration test requirements of OM-6, Section 4.6.1.6, for the standby liquid control pumps (SBLC). The Code l
requires that the frequency response range of the vibration measuring i
equipment to be from one-third minimum shaft rotational speed to 1000 Hz. The licensee is proposing to use the existing instrumentation, which does not meet the Code requirements, and utilize maintenance equipment if vibration test results for a SBLC pump fall within the alert or required action range.
The vibration monitoring instrumentation for the SBLC pumps would have a frequency response range of 2.06 to 21000 Hz to comply with OM-6.
This is based on one-third running speed of the SBLC pump (123 rpm) for the frequency response range.
The lower limit of the range is to allow for detection of problems such as bearing oil whirl. The licensee's current vibration instrument has a frequency response range from 5.8 to 10,000 Hz. Additional instrumentation available on site does not meet the Code requirements; therefore, the licensee has no means to comply with the requirements for measuring the vibration in the low frequency range for the SBLC pumps. Though the licensee has not discussed procurement of instrumentation that meets the requirements, the staff has determined that vibration equipment with the required frequency response range is commercially available.
Requiring the licensee to meet the Code requirements immediately is impractical because of the limitations of the currently available instrumentation.
Imposition would be a burden because a plant shutdown might result if the testing cannot be performed immediately which challenges safety systems and stresses equipment. A period of time is required to procure the vibration equipment..Therefore, based on the impracticality and considering
l i the burden of immediate compliance, interim relief is granted, pursuant to 10 CFR 50.55a(f)(6)(i), for a period of one year. During the interim period, the licensee should procure equipment that meets the Code frequency response range requirements or provide additional justification regarding the burden of obtaining measurements in the lower range compared to the information gained if the measurements were available. The licensee's proposed alternate method of testing, while not an acceptable long term solution, should provide i
reasonable assurance of operational readiness in the interim period because I
the frequency response range of the available instruments will allow identification of problems other than oil whirl.
2.3 Relief Recuest RR-P-7 The licensee has requested relief from the acceptable instrument accuracy requirements of ASME/ ANSI OMa-1988, Part 6, Section 4.6.1.2 and Table 1, for i
instruments which do not meet the Code full-scale range and instrument i
accuracy requirements. The licensee has proposed to utilize the installed instrumentation for several instruments listed to measure flow and pressure.
2.3.1 Licensee's Basis for Recuestina Relief i
i The licensee states: "The original installed instrumentation associated with these pumps was not designed with the instrument accuracy and ranges of OM Code ISTB Table 4.6.1-1 taken into consideration. The actual instrument ranges and loop accuracies are itemized on the attached sheets [see Section 2.3.2 below).
These attached sheets provide information relative to the range, individual accuracy and total loop accuracy of those instruments that i
do not satisfy the OM requirements."
2.3.2 Alternate Testina i
The licensee proposes: " Test gages calibrated to i 0.5% accuracy will be utilized for RHR and Core Spray pump inlet pressure measurement.
For all other pump parameters the installed instrumentation will be utilized. The installed instrumentation should provide data that is sufficiently accurate to i
allow assessment of pump condition and to detect pump degradation."
2 A discussion of each instrument not meeting the Code requirements is presented below.
1(2)E11-PI-R003A-D exceed the range limit of three times the reference value, however the additional gage range results in approximately 1 psig maximum allowable variance in the measured parameter.
(i.e.
02 x 550 -
11 versus.02 x 600 = 12).
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1(2) Ell-FI-R603A(B) exceed the range limit of three times the reference value and the total loop accuracy is greater than the code allowable.
The instrument range was selected due to design considerations for LPCI flow rate (17,000 gpm for two pumps), whereas, the IST pump test flow rate is approximately 7700 gpm. The code maximum allowable variance in measurement would be approximately 480 gpm (i.e.
02 x 24,000) and the actual maximum variance is 625 gpm (i.e.
025 x 25,000).
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1(2)E11-PI-R600A(B) exceed the maximum code allowable total loop accuracy, however, the indicator used has a full scale range less than that allowed.
The maximum code allowable variance in measurement is 17 psig (.02 x 870) for unit I and 18 psig for unit 2 (.02 x 924).
However, by using a gage with a range less than allowed, the actual maximum allowable variance is 14 psig (.028 x 500) for unit I and 11 psig (.021 x 500) for unit 2.
Therefore, the actual accuracy is within the code allowable for the maximum allowable range.
1(2)E41-PI-R004 exceed the range limit of three times the reference value. However, the gages are calibrated to i 1% full scale accuracy, i
which results in the final variance being within the maximum allowable by the code.
(i.e. 1.6 psig versus I psig for unit I and 1.8 psig versus I psig for unit 2) 1(2)E41-FI-R613 exceed the maximum code allowable total loop accuracy, however, the indicator used has a full scale range less than that allowed. The maximum variance allowable by the code is 255 gpm (.02 x 12750), whereas, the actual maximum variance is 125 gpm (.025 x 5000) for unit I and 145 gpm (.029 x 5000) for unit 2.
Therefore, the actual accuracy of the instrument loop is less than that allowable by the code.
1(2)E51-PI-R002 exceed the range limit of three times the reference value. However, the gages are calibrated to i 1% full scale accuracy,
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which results in the final variance being within the maximum allowable by the code.
(i.e. i.4 psig versus 1 psig for unit I and 1.8 psig versus 1 psig for unit 2).
1(2)E51-F1-R613 exceed the maximum code allowable total loop accuracy, however, the indicator used has a full scale range less than that allowed. The maximum variance allowable by the code is 24 gpm (.02 x 1200), whereas, the actual maximum variance is 15 gpm (.025 x 600) for unit I and 17 gpm (.029 x 600) for unit 2.
Therefore, the actual accuracy of the instrument loop is less than that allowable by the code.
2P41-PI-R306A-D exceed the maximum code allowable total loop accuracy, however, the indicator used has a full scale range less than that allowed. The maximum variance allowable by the code is 7 psig (.02 x 363), whereas, the actual maximum variance is 6 psig (.021 x 300).
Therefore, the actual accuracy of the instrument loop is less than that allowable by the code.
2.3.3 Evaluation The licensee has requested relief from the Code accuracy and full-scale range requirements for several pressure and flow indicators used for inservice testing of pumps.
The eight RHR pump discharge pressure indicators, 1(2)E11-PI-R003A-D, exceed the full-scale range requirements of OM-6, Section 4.6.1.2(a). The maximum variation in the pressure measurement with the current instrumentation is 12 psig.
Compared with the Code allowable maximum accuracy variance of
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11 psig, there is a 1 psig variance above the Code accuracy requirement.
Requiring the licensee to install instrumentation that meets the Code i
requirements would not be justified by the limited difference in the information obtained. Compliance with the Code requirements would result in a hardship without a compensating increase in safety because the information gained from a more accurate pressure indicator would not greatly effect the ability to assess the condition of an RHR pump if it were operating in the alert or required action range. The installed RHR pump discharge pressure indicators provide an acceptable level of assurance of their operational readiness; therefore, the alternative is authorized, pursuant to 10 CFR 50.55a(a)(3)(ii), as requested.
The four flow indicators in the RHR systems,1(2) Ell-FI-R603A(B), exceed the i
full-scale range requirements of OM-6, Section 4.6.1.2(a) and the maximum Code l
allowable total loop accuracy requirements of OM-6, Table 1.
The maximum i
variation in the flow measurement with the current instrumentation is 625 gpm.
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Compared with the Code allowable maximum accuracy variance of 480 gpm,-there is a 145 gpm variance above the Code accuracy requirement. This large j
variance could potentially impact the determination of operation of the pump in the alert or required action ranges.
Immediate imposition of the Code i
requirements is impractical based on the design limitations of the installed instrumentation and would be a burden on the licensee. Therefore, interim relief is granted, pursuant to 10 CFR 50.55a(f)(6)(i), for a period of one year to allow the licensee to determine a method to measure flow within the accuracy requirements of the Code or to describe an alternate method to compensate for the variance, such as tightening the acceptance criteria for these pumps.
The following instruments exceed the maximum Code allowable total loop accuracy requirements given in OM-6, Table 1:
the four core spray discharge pressure indicators, 1(2) Ell-PI-R600A(B); the two high pressure coolant injection flow indicators,1(2)E41-FI-R613; the two reactor core isolation cooling (RCIC) flow indicators,1(2)E51-FI-R613; and the four plant service water discharge pressure indicators (unit 2 only), 2P41-PI-R306A-D.
These indicators have a full-scale range less than the maximum allowed by the Code.
This results in the actual variance having a value less than the maximum variance allowed by the Code. The installed instrumentation provides an acceptable level of safety because the variance in the actual test results is more conservative than that allowed by the Code. Therefore, the alternative is authorized, pursuant to 10 CFR 50.55a(a)(3)(i), as requested.
The following instruments exceed the full-scale range requirements of OM-6, Section 4.6.1.2(a): the two high pressure coolant injection pump inlet pressure indicators,1(2)E41-PI-R004 and the two reactor core isolation cooling (RCIC) pump inlet pressure indicators,1(2)E51-PI-R002.
These indicators are calibrated to an accuracy of 11% of full scale. This results in the actual variance having a value less than the maximum variance allowed by the Code. The installed instrumentation provides an acceptable level of quality and safety because the variance in the actual test results is more conservative than that allowed by the Code. Therefore, the alternative is authorized, pursuant to 10 CFR 50.55a(a)(3)(1), as requested.
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t i 2.4 Relief Reouest RR-P-2 l
The licensee has requested relief-from the flow rate measurement requirements of OM-6, Section 4.6.5, for the standby liquid control pumps. The licensee is proposing to measure flow rate by measuring the change in tank level over the i
duration of the test.
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2.4.1 Licensee's Basis for Reauestina Relief The licensee states: " Instrumentation was not provided during construction to i
measure the required flow rate."
e 2.4.2 Alternate Testina The licensee proposes: The system is aligned so that it forms a closed loop l
through the test tank. Flow is recirculate through the pump and tank until j
j conditions stabilize, and then the system is realigned to perform the testing described below.
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i Flow rate is measured by the change in the-standby liquid control test tank level during a two minute test period.
The standby liquid control (SBCL)
I 4
system is aligned so that each pump takes suction from a demineralized water i
source and discharges through a throttle valve adjusted to obtain a reference i
discharge pressure. The level of the test tank is.then measured and the pump is run for two minutes. After the two minute run, the tank level is again i
measured. Flow rate is then determined by the following equation.
l Flow (gpm) - a Tank level (in.) x 4.91 aal/in.
2 min.
i For a situation in which the flow rate is measured by instrument, a' 0-100 gpm instrument would normally be used for the SBCL pump flow rate of approximately l
43 gpm. The required accuracy of this instrument would be i 2% or i 2 gpm.
This corresponds to a i 4 gallons total in'two minutes, which is equivalent to 1
i 0.81 inches level change in the test tank. Therefore, the accuracy of the measured flow rate should be well within Code allowance."
y i
i 2.4.3 Evaluation The Code requires that a flow meter be installed in the pump test circuit.
Since no flow meter is installed in the system in order to meet the Code, the licensee must either develop a method that will provide the flow rate within the Code accuracy requirements or install a flow meter. The licensee has proposed to measure the change in tank level over the duration of the test and a
calculate the flow rate. The licensee has shown=that the Code accuracy j
requirements are equivalent to measuring tank level to within a 0.81" band-width in the SBLC tank. The use of tank level to calculate flow, therefore, provides an acceptable level of safety as an alternative to the Code e
requirements. The calculation should be included in the test procedure.
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Based on the determination that calculating a flow rate based on the change in SBLC tank level provides an acceptable level of safety to the Code requirements, the alternative is authorized, pursuant to 10 CFR 50.55a(a)(3)(i), as requested.
l 2.5 Relief Reauest RR-P-3 i
The licensee has requested relief from the differential pressure measurement requirements of OM-6, Section 4.6.2.2, for the three sets of residual heat a
removal service water, plant service water, and standby diesel generator pumps. The licensee has proposed to utilize a measurement of the river water level at the intake structure to calculate the inlet pressure for these submersible pumps.
i i
2.5.1 Licensee's Basis for Reauestina Relief The licensee states: "No inlet pressure instrumentation is provided."
i 4
2.5.2 Alternate Testina j
j The licensee proposes: " Inlet pressure is determined for this group by measuring the river level at the intake structure. The differential pressure is then:
i AP = P + (114.5 ft - River Water Level) x 0.433 Where AP is the differential pressure and P is the outlet pressure. This method of measurement is well within the code requirements for the determination of the differential pressure."
{
2.5.3 Evaluation I
Inlet pressure measurement is not required by OM-6 except as used to determine differential pressure.
Paragraph 4.6.2.2, " Differential Pressure," of OM-6 allows that differential pressure may be determined by taking the difference between the pressure in the inlet pipe and the pressure at a point in the j
discharge pipe.
For submersible pumps such as these, the inlet pressure is i
effected by the pressure of the bay and this must be factored into the a
4 calculation as the licensee has proposed. The calculation must be included in the implementing procedure. The licensee's proposal for determining differential pressure is in accordance with the Code requirements, including accuracy, and relief is not required.
l t
2.6 Relief Recuest RR-V-4 The licensee is requesting relief from the corrective action requirements of Section XI, Paragraphs IWV-3417(b) and IWV-3523, for valves exercised only during cold shutdorn: :nd refueling outages.
The licensee is proposing to not enter a mode of plant 'operattor, that requires a specific component to be operable if the component is discovered to be inoperable based on inservice testing. The Code requires the corrective action to be completed prior to plant startup.
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2.6.1 Licensee's Basis for Reouestino Relief I
5 i
The licensee states: "The Technical Specifications provide the requirements and plant conditions necessary for plant startup."
1 2.6.2 Alternate Testino 3
The licensee proposes: "The Technical Specifications shall be utilized to determine the status of the plant required for startup. However, assurance will be made that if the plant is started up from the cold shutdown or refueling mode with a component being inoperable due to corrective action as required by IWV-3417(b) or IWV-3523, a mode of operation that would prevent performance of the post corrective action testing will not be entered into."
2.6.3 Evaluation The Code requires that, for valves tested during cold shutdown or refueling 1
outages which are declared inoperable and require corrective action, the condition shall be corrected prior to plant startup. This is to allow valve i
replacement or repair in a plant operating mode where the valve will not be e
required to perform its safety function.
The licensee has proposed to allow the plant Technical Specifications (TS) to govern the conditions for plant i
startup.
In addition, the licensee has stated that assurances will be made l
l such that a mode of plant operation will not be entered if a component was declared inoperable and corrective action could not be implemented in that mode of operation.
i As stated in the contractor's Technical Evaluation Report enclosed in the a
Safety Evaluation dated December 10, 1991, it is impractical to require the licensee to delay plant startup in order to repair a valve in a flow path addressed in the plant TS which is not required to be operabl for plant startup and operation by the plant TS.
Relief was granted for valves which were addressed in the licensee's TS. However, relief was denied for valves in 9
flow paths which are not specifically addressed in the plant TS. The licensee was advised that if relief was desired from IWV-3417(b) for cny of these valves, the licensee should submit relief requests for specific valves. Al so, 1
j in these relief requests, the licensee should provide the basis to justify the relief request in terms of the safety function of the specific valves. The revised relief request does not address the remaining valves.
Therefore, the status of this relief request remains unchanged.
2.7 Relief Reouest RR-V-30A i
The licensee has requested relief from the check valve testing requirements of Section XI, Paragraph IWV-3520, for the containment isolation valves listed below. The licensee is proposing to verify reverse flow closure each refueling outage by performance of a leak test.
These valves are not subject to a local leak rate (Type C) test per 10 CFR 50, Appendix J.
J E21-F044A & B E41-F021 E41-F022 2E51-F040 E41-F040 E41-F046 E41-F049 E51-F001 E51-F002 E51-F021 E51-F028 E51-F040 2E21-F044A & B
. I 2E41-F021 2E41-F022 2E41-F040 2E41-F046 2E41-F049 2E51-F001 2E51-F002 2E51-F021 2E51-F028 2.7.1 Licensee's Basis for Reouestino Relief The licensee states: "These valves function as containment isolation barriers.
i The only viable means of proving closure is by performing a leak rate or pressure test. To perform the tests quarterly would require removing the associated systems from operation. To perform the tests at cold shutdown poses additional requirements on testing and operations personnel involved in other shutdown related activities.
i Since these valves only provide a containment barrier function and allowable leakage limits are significantly greater than allowed for containment isolation valves, and the fact that these valves are not exposed to severe operating conditions which would promote rapid degradation, leak rate or pressure testing at a refueling outage frequency will provide sufficient test results to ensure a margin of safe component operability.
Appendix J testing requirements were deleted in 1988.
Review of testing and j
maintenance history since that time does not indicate any abnormal failure rate or maintenance requirements for these valves.
l 1(2)E21-F044A,B: These valves are located in the jockey pump recirculation line back to the suppression pool.
Performing the pressure test quarterly would require removing the associated jockey i
pump (s) from service and would likely result in not maintaining the associated train of RHR and Core Spray piping full of water as required by Technical Specifications. This would result in unnecessary ECCS unavailability and potential entries into Technical Specification 3.0.3.
Per Technical Specifications the RHR i
and Core Spray Systems are normally required to be operable during brief periods of cold shutdown. This testing can be safely and efficiently performed during refueling outage.
1(2)E41-F021 and F049 - Turbine Exhaust to suppression pool check valves 1(2)E41-F022 AND F040 - Turbine Exhaust Drain to suppression pool check valves 1(2)E41-F046
- Minimum flow to suppression pool check valve i
Testing any of these valves quarterly during power operation will result in removing the HPCI system from the operable condition and would cause unnecessary system unavailability.
To perform the required valve line ups, equipment set up and perform the test would take approximately eight (8) hours for each test.
Performing the tests at cold shutdown poses additional test requirements on testing and operations personnel already involved in other shutdown activities.
Because HPCI is a standby system, which is normally operated during surveillance testing, these valves do not experience service conditions, which would promote rapid degradation.
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1(2)E51-F001 and F040 - Turbine Exhaust to suppression pool check valves j
1(2)E51-F002 and F028 - Turbine Exhaust Drain to suppression pool check valves-l 1(2)E51-F021
- Minimum flow line to suppression pool check value Testing any of these valves quarterly during power operation j
will result in removing the RCIC system from the operable condition and would cause unnecessary system unavailability.
To perform the required valve line ups, equipment set up and l
q perform the test would take approximately eight (8) hours-i for each test.
Performing the tests at cold shutdown poses additional test requirements on testing and operations 3
personnel already involved in other shutdown activities.
i i
Because RCIC is a standby system, which is only operated during surveillance testing, these valves do not experience i
service conditions which would promote rapid degradation.
l 2.7.2 Alternate Testina i
The licensee proposes: " Reverse flow closure at each refueling outage by performance of leak rate test similar to an Appendix J type test. The equipment utilized for this testing allows measurement of the leakage rate from the test boundary and trending of any significant changes in leakage characteristics. Testing at a frequency commensurate with that prescribed by 10 CFR 50, Appendix J is appropriate considering the containment isolation function of the valves in question."
2.7.3 Evaluation l
The licensee has requested relief from the Code frequency test requirements 4
for closure verification of check valves in the jockey pump recirculation line back to the suppression pool, the HPCI system, and the RCIC system. The Code require that these valves be tested quarterly to verify the functioning of the valve. The licensee has proposed to verify closure of these valves on a refueling outage frequency with an Appendix J type test.
Each system is 4
discussed separately below.
j Jockey pump Recirculation Check Valves j
Relief was granted from the Code frequency test requirements in a previous NRC SE which was transmitted to the licensee in a letter dated December 10, 1991.
4
)
HpCI Check Valves 1
The licensee stated in their June 5,1992, submittal that to conduct the check valve testing would require removing the HPCI system from operable status.
The licensee also stated that each of the check valve tests would take 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to complete.
Considering there are 5 check valves to be tested in each system, the total test time should be approximately 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br />.
Requiring the licensee to conduct this testing quarterly would be a burden and impractical because the HPCI system would be required to remain in a limiting condition of operation (LCO) for an extended period of time.
Performing tnis testing during cold shutdowns would also be a burden and impractical because it could delay plant startup.
i
- j The licensee has proposed to perform reverse flow closure testing every refueling outage by using a leak rate test similar to an Appendix J test.
In final rulemaking effective September 8,1992, published in the Federal Reaister, Volume 57, No. 152, Thursday, August 6, 1992, the staff approved the 1989 Edition of ASME Section XI which references OM-10 as alternative rules i
for inservice testing of valves. Section 4.3.2.2 of OM-10 states that if l
exercising is not practicable during plant operation or cold shutdowns, it may be limited to refueling outages. The licensee's proposed testing frequency is l
consistent with the testing frequency recommended by the OM-10~ Code which has l
been approved for use by the NRC.
Relief is no longer required, related to full-stroko exercising during refueling outages, based on rulemaking effective September 8, 1992, pursuant to 10 CFR 50.55a(f)(4)(iv), provided the licensee implement all related OM-10 t
requirements.
I fLGIC Check Valves l
The licensee stated in their June 5, 1992, submittal that to conduct the check valve testing would require removing the RCIC system from operable status.
The licensee also stated that each of the check valve tests would take 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to complete. Considering there are 5 check valves to be tested in each system, the total test time should be approximately 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br />. Requiring the l
licensee to conduct this testing quarterly would be a burden and impractical-l because the RCIC system would be required to remain in a LC0 for an extended period of time.
Performing this testing during cold shutdowns would also be a burden and impractical because it could delay plant startup.
The licensee has proposed to perform reverse flow closure testing every refueling outage by using a leak rate test similar to an Appendix J test.
In final rulemaking effective September 8, 1992, published in the Federal Reaister, Volume 57, No.152, Thursday, August 6,1992, the staff approved the 1989 Edition of ASME Section XI which references OM-10 as alternative rules for inservice testing of valves. Section 4.3.2.2 of OM-10 states that if exercising is not practicable during plant operation or cold shutdowns, it may be limited to refueling outages. The licensee's proposed testing frequency is consistent with the testing frequency recommended by the OM-10 Code which has been approved for use by the NRC.
Relief is no longer required, related to full-stroke exercising during i
refueling outages, based on rulemaking effective September 8,1992, pursuant to 10 CFR 50.55a(f)(4)(iv), provided the licensee implement all related OH-10 requirements.
2.8 Relief Reauest RR-V-18 The licensee has requested relief from the check valve exercise procedure requirements of IWV-3522(a) for the reactor water clean up (RWCU) valves G31-F039 and G31-F203. The licensee is proposing to verify closure of these check valves each refueling outage during local leak rate testing.
2.8.1 Licensee's Basis For Reouestina Relief The licensee states: "The normally open check valves are located in the RWCU return flow path to the reactor vessel via each feedwater line. To establish the necessary test boundary for each of these valves will require closure of the manual feedwater valve, B21-F0llA(B), which is located inside primary containment.
Entry into primary containment is not possible during normal operation due to the nitrogen inerted atmosphere.
To perform the test during cold shutdown would require the same test bounJary as above. Therefore, performing the test would require: de-inertion of the primary containment, multiple personnel entries into potential high radiation exposure area, valve manipulation, set up of test equipment, actual test performance, evaluation of test results, re-establishment of normal system alignments and Technical Specification required nitrogen inertion of the containment upon startup. The minimum estimated time to perform such testing, not including time to de-inert and re-inert the containment, is eight hours.
Therefore, due to the problems associated with an inerted containment, multiple personnel containment entries to support the test, ALARA concerns and the actual test duration, performance during cold shutdown seems unwarranted."
2.8.2 Alternate Testina The licensee proposes: "The check valve will be confirmed to close each refueling cutage during the local leak rate tests."
2.8.3 Evaluation The Code requires that these check valves be tested quarterly to verify their functional capability. The valves are simple check valves that do not have local or remote position indication. The only practical method to verify closure is with a leak test.
As stated in the staff's SE of December 10, 1991, testing these valves quarterly would be impractical because flow in one of the feedwater lines would have to be interrupted which would cause a reactor water level transient and could result in a reactor trip. The licensee stated that in order to perform testing during cold shutdowns, the licensee would require access to manual feedwater valve B21-F011A(B) which is located in primary containment.
Access to primary containment is restricted during power operations and cold shutdowns because the containment is inerted.
Requiring the licensee to de-inert the containment to conduct the check valve testing would be impractical and a burden because this could delay the plant start-up.
The licensee has proposed to conduct local leak rate testing to confirm check valve closure during refueling outages.
Access to the manual feedwater valve would be available during refueling outages.
In final rulemaking effective September 8,1992, published in the Federal Reaister, Volume 57, No.152, Thursday, August 6, 1992, the staff approved the 1989 Edition of ASME Section XI which references OM-10 as alternative rules for inservice testing of valves. Section 4.3.2.2 of OM-10 states that if exercising is not practicable during plant operation or cold shutdowns, it may be limited to refueling outages.
The licensee's proposed testing frequency is consistent with the
- testing frequency recommended by the OM-10 Code which has been approved for use by the NRC.
Relief is no longer required, related to full-stroke exercising during refueling outages, based on rulemaking effective September 8, 1992, pursuant to 10 CFR 50.55a(f)(4)(iv), provided the licensee implement all related OM-10 requirements.
2.9 Relief Reauest RR-V-25 The licensee has requested relief from the exercise procedure requirements of Section XI, Paragraph IWV-3522(a), for the plant service wzter pump discharge check valves, P41-F311A thru D and 2P41-F311A thru D.
The licensee is a
proposing to verify closure quarterly by the performance of the operating pump and observation of the idle pump in the train.
2.9.1 Licensee's Basis for Recuestino Relief The licensee states: "There are no direct means to verify closcre of these valves."
2.9.2 Alternate Testino The licensee proposes: " Closure must be verified to ensure that flow from an operating pump on the train is not diverted back through a non-operating pump and thereby degrading the performance of the operating pump.
Closure of each valve is confirmed quarterly during service water pump testing.
Each pump in each train is tested individually for IST. During the i
pump test, the discharge check valve on the idle pump is proven to be closed i
sufficiently to perform its safety related function by satisfactory performance of the pump being tested and by visual observation that the idle pump is not rotating backwards.
Note: Opening of each check valve is verified by the associated pump satisfying its Technical Specification required flow."
2.9.3 Evaluation In the ASME Code,Section XI, Paragraph IWV-3522(a), the Code states that conformation of closure can be made by visual observation, by an electrical signal initiated by a position indication device, by observation of appropriate pressure indications in the system, or by other positive means.
The method of testing proposed by the licensee is considered a positive means of verifying check valve closure.
In addition, since the licensee has proposed to conduct this testing quarterly, relief is not required.
3.0 NEW RELIEF RE0 VESTS 3.1 Relief Reauest RR-V-42 The licensee has requested relief from the stroke-time and corrective action requirements of Section XI, Paragraphs IWV-3413(a) and IWV-3417(a), for the i
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1
' main steam isolation valves listed below.
The licensee is proposing to set a minimum and maximum allowable stroke time for the valves.
If any of the valves do not meet this stroke time criteria, the specific valve will be declared inoperable and the applicable Technical Specification action statement will be entered.
1821-F022A-D-IB21-F028A-D 2B21-F022A-D 2B21-F028A-D 3.1.1 Licensee's Basis for Reauestino Relief The licensee states: "IWV-3413(a) requires that the Owner specify the limiting value of full-stroke time for each power operated valve.
For all valves, l
l except the MSIV's, which require stroke timing this limiting value is a maximum allowable stroke time. However, the design basis for the MSIVs j
imposes a minimum and a maximum allowable stroke time of 3 to 5 seconds respectively. Therefore, the MSIVs have a 2 second window of acceptable i
operating times. Applying a 50% increase limit from the previous test to a valve which must stroke in a 2 second window is impractical. When the criteria of IWV-3413(b) are also applied, valves with stroke time of s 10 seconds only require timing to the nearest second, then the requirements of IWV-3417(a) become even more impractical."
i 3.1.2 Alternate Testina i
The licensee proposes: "The MSIVs will be stroke timed during cold shutdown per Cold Shutdown Justification CS-9 and their closing time will be confirmed to be between 3 seconds and 5 seconds. As soon as it is recognized that an' MSIV does not meet this criteria, it will be declared inoperable'and the i
applicable Technical Specification Action statement entered."
3.1.3 Evaluation I
Each unit at Hatch has eight main steam isolation valves (MSIVs) in four main j
steam lines. When closed, these valves form part of the-nuclear system process barrier for openings outside containment and part of the pressure l
barrier for nuclear system breaks inside containment.
The Code requires that the limiting value of full stroke time of the MSIVs be specified by the licensee.
For valves that have stroke times of 10 seconds or 1ess, the stroke times shall be measured to the nearest second. The licensee j
has proposed to set upper and lower limits to the stroke time based on the Technical Specification (TS) limits.
The TS require the valves to close between 3 - 5 seconds. According to the UFSAR, the upper 5 second limit is set to protect the fuel barrier against a loss of cooling in the event of-a main steam line break. The lower 3 second limit is established in order for the action of the valve closure not to exceed NSSS design limits. According to the TS, the valves are declared inoperable if the stroke time falls outside of this window and an 8-hour LCO is entered. The upper and lower limits defined in the TS establish a very narrow window of acceptance which is more conservative than the' criteria to establish an increased frequency of testing as stated in IWV-3417(a).
l I !
i Therefore, the licensee's proposed method of testing provides an acceptable i
level of quality and safety as an alternative to the Code requirements.
f i
Based on the determination that the proposed alternate method of testing provides an acceptable level of safety, the alternative is authorized, j
pursuant to 10 CFR 50.55a(a)(3)(1), as requested.
j l
3.2 Relief Reauest RR-V-43 l
The licensee has requested relief from the valve leak rate test requirements of Section XI, Paragraphs IWV-3421 and IWV-3422, for the transverse incore l-l probe (TIP) system outboard isolation explosively actuated shear valves, IC51-l l
Shear A thru D and 2C51-Shear A thru D.
The licensee has proposed to allow l
the manufacturer to leak test a sample lot of valyes prior to delivery.
3.2.1 Licensee's Basis for Reauestina Relief i
The licensee states: "These valves are explosive actuated shear valves. The l
shear valve isolates the TIP tubing by shearing the tube and TIP drive cable, and by jamming the sheared ends of the tubing into a teflon coating on the l
shear valve disc. Thus, the shear valves cannot be local leak rate tested l
without destroying the drive tube."
3.2.2 Alternate Testino 1
The licensee proposes: "Each lot of shear valves is sample leakage tested by the manufacturer prior to delivery."
3.2.3 Evaluation Each transversing incore probe (TIP) drive mechanism has a shear valve located between the mechanism and a ball valve in the guide tube to provide outboard isolation of the guide tube in the event that containment isolation is j
required. When the TIP is beyond the ball valve, which is normally used to provide outboard isolation, and power to the TIP system has failed,'the shear valve is actuated manually from the control room. This action actuates the shear valve detonation squib which shears the guide tube and drive cable and isolates the guide tube.
The licensee stated that these valves are Category A which are subject to leak rate testing. However, these valves should be designated Category D valves which are subject to the requirements of IWV-3600.
Table IWV-3700-1 states that leak testing of Category D valves is not required. Testing of Category D valves involves a sample of the explosive charges. The licensee should correctly categorize these valves and review the requirements of IWV-3600 to determine if the testing can be performed in accordance with the Code and revise the IST program appropriately. Relief as requested is inappropriate.
3.3 Relief Recuest RR-V-44 The licensee has requested relief from the exercise procedure requirements of IWV-3412(a) and the test procedure requirements of IWV-3522 for all valves tested at cold shutdowns. The licensee is proposing to use the ASME OM Code, i
1990 Edition, Section ISTC 4.2.2(g), for scheduling testing of valves during cold shutdowns.
3.3.1 Licensee's Basis for Reauestino Relief The licensee states: "The ASME OM Code-1990 Edition, paragraph ISTC 4.2.2(g) provides acceptable guidance for testing of valves, which are justifiably tested at cold shutdown frequency."
3.3.2 Alternate Testino The licensee proposes: " Testing of valves that is justified on a cold shutdown testing frequency will be performed per 0M Code paragraph ISTC 4.2.2(g) as outlined below.
a.
Testing will commence as soon as cold shutdown is achieved, but no later than 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after shutdown, and continue until complete or the plant is ready to return to power.
b.
Completion of all valve testing is not a pre-requisite to return to power.
c.
Any testing not completed during one cold shutdown should be performed during any subsequent cold shutdowns starting from the last test performed at the previous cold shutdown.
d.
For planned cold shutdowns, where ample time is available and testing of all valves identified for cold shutdown test frequency in the IST program will be accomplished, exceptions to the 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> may be taken."
3.3.3 Evaluation The Code requires that valves that cannot be full-stroke exercised during plant operation shall be full-stroke exercised during cold shutdowns.
In addition, if only limited operation of the valve is practical during plant operation, then the valve should be part-stroke exercised during power operation and full-stroke exercised during cold shutdowns.
The licensee has proposed to conduct cold shutdown testing of valves, which have been designated for testing at a cold shutdown frequency, in accordance with criteria outlined in Section 3.3.2 of this SE.
These conditions are similar to the requirements of the 1990 Edition of the OM Code, Paragraph ISTC 4.2.2(g).
In final rulemaking effective September 8,1992, published in the Federal Recister, Volume 57, Number 152, Thursday, August 6,1992, the staff approved the 1989 Edition of ASME Section XI. The requirements for pump and valve testing in the 1989 Edition of ASME Section XI reference the Operations and Maintenance (OM) Standard, Part 6 and Part 10, as alternative rules for Subsections IWP and IWV.
The OM Code, 1990 Edition, Section ISTC 4.2.2(g) is identical to Section 4.2.1.2(g) in OMa-1988, Part 10.
The OM Code, 1990 Edition, Section ISTC 4.2.2(g) provides an acceptable level of safety compared with ASME Section XI, Paragraph IWV-3412(a).
. Based on the determination that the alternate method of testing proposed-provides an acceptable level of quality and safety, the alternative is authorized, pursuant to 10 CFR 50.55a(a)(3)(i), as requested.
Principal Contributor: Joseph Colaccino j
Date:
April 5, 1993 1
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Table Georgia Power Company Edwin I. Hatch Nuclear Plant, Units 1 and 2 NRC Safety Evaluation Docket Numbers 50-321 and 50-366 Itm Nunter Description from NRC SE GPC Actions as Described in April 16, 1992, Current SE ard (Relief Dated Decewber 10, 1991 and June 5, 1992, IST Program StAmittels Remaining Actions Request)
Item 1 The licensee requested relief from severat section XI Items 1 and 2 were concerned with the use of Relief reques*
(RR P 6) requirements and proposed to measure vibration the ASME ON Code in lieu of ASME Section XI for evaluated using velocity, delete bearing terperature measurements, and pwp testing at Plant Match. This relief ASME/ ANSI OMa-1988, analyze hydraulic parameters in accordance with OM-6.
request was initially developed to apply only Part 6 (OM 6).
The purp test guidelines of ASME/ ANSI OMa-1988, Part 6 portions of the OM Code while still utilizing (OM-6) are allowed by ASME Code Case N-465 and portions of the ASME Section XI. Code Case N-Relief granted for referenced in NRC Regulatory Guide 1.147 and allowed 465 attows the use of the OM Code in its centrifugat pwps by 10 CFR 50.55a. However, the Licensee was requested entirety in lieu of ASME XI. Therefore, RR P-6 (a)(3)(1),
to ensure that pwp testing conplies with all testing has been revised to address the use of the ASME requirements of OH-6.
Relief is not required if OM-6 OM Code 1990 Edition, Section ISTB, for those Relief denied for att is used in its entirety.
pw ys required to be tested by ASME Section XI vertical line shaft and incitMes justification for portions of the pwps except SOSW pupp.
OM Code which GPC requests relief.
Interim relief granted Relief Requests RR-P-2 and RR-P-3 were revised f or SDSW pwp as a result of this relief request and (f)(6)(i).
evaluations for these relief requests were included in the SE.
Interim relief granted for frequency response range of SBLC rw ps.
Item 2 This relief request did not specifically define the See it m 1.
See item 1.
(RR P-6) sections that the licensee wanted the staff to review and grant relief. The licensee should comply with att requirements of Section NI, IWP, unless the staff has granted relief from specific requirements. - - -
Item Nunber Description f rom NRC SE GPC Actions as Described in April 16, 1992, Current SE and (Relief Dated Decemler 10, 1991 and June 5, 1992, tsi Program submittats Remaining Actions Request)
Item 3 A letter dated October 8, 1990, requested relief from Item 3 concerned the status of an interim The licensee has the Code vibration instrunent accuracy requirements relief request, dated 10/8/90, regarding the addressed the concerns until January 1, 1991. After the deadline, use of vibration instrunents that did not meet of the anomaty. New instruments meeting the Code vibration instrunent the calibration accuracy requirements of ASME instrunents are in use accuracy requirements would be used. Since the section XI.
The interim relief was effective and relief is no longer deadline had passed when the SE/TER was issued, the until 1/1/91. New instrunents meeting the regJired. No further licensee was requested to withdraw the relief request, accuracy requirements are now used at Plant NRC action is required.
Match. As the interim relief has empired and is no longer requised, no further actions are
- required, item 4 Relief was denied for the instrument range item 4 stated this relief request did not Relief granted for RMR (RR P-7) reqJirements of several punps in the 157 program provide sufficient detail for all system ptrp discharge pressure because the licensee did not provide adequate instrunentation involved. Therefore, the indicators (a)(3)(ii).
technical justification for not complying with the relief request was revised to list all Code instrument accuracy requirements.
applicable instrumentation and to provide Interim relief granted adjitional justification for each individual for RNR flow indicators case.
(f)(6)(1).
Relief granted for following: CS discharge pressure indicators; HPCI flow indicators; RCIC flow indicators; PSW discharge pressure indicators (unit 2 only); NPCI ptep intet pressure indicators; RCIC punp intet pressure indicators (a)(3)(1).
Item 5 Relief request RR-P-4 adjressed the requirement to Relief request RR-P-4 has been withdrawn.
No further NRC action RR P 4 measure or observe bearing lubricant level or pressure is required.
f rom several punps in the IST program. Since these bearings are in the process fluid flow paths, there is no parameter to be observed and relief is not necessary..
s Item Nutber Description from NRC 5E GPC Actions as Described in April 16, 1992, Current SE and (Relief Dated Deceerter 10, 1991 and June 5, 1992, Isi Program Sulaittels Remaining Actions Request)
Item 6 Relief was denied for valve E51 F016 because the valve Relief Request RR V-2 contained a typographical Relief is granted for (RR-V 2) was only identified in the relief request and is not error. Valve 1E51 7007 was incorrectly valve 1E517007 based included in the IST program, referenced as 1E51-F016. Valve 1E51-F007 is on relief being granted identical to the unit 2 valve 2E51 F007 which for valve 2E51-F007 in was included in this relief request and the Decenber 10, 1991, approved in the December 10, 1991, SE.
Relief SE.
No further from the Code requirements for valve 1E51 F007 evaluation of this would have been granted if the valve had been relief request is listed correctly in the original relief required.
request.
Item 7 The licensee indicated in section 2.10 of their IST Calculations performed using equations in Response provided to program that valves that perform both CIV and Piv Section XI indicate that the CIV teak rate test the NRC Nuvenber 17, functions are tested to CIV acceptance criteria. In is conservative. Additional calculations and 1992.
order to use only CIV testing for dual function testing will be performed to surport RR V-4.
valves, documentation should be provided in the IST program that demonstrates for each effected valve that the proposed CIV teak rate testing bounds the Section XI leak rate testing or otherwise verifles the PIV function of the valves.
Item 8 Relief was denied to attow plant Technical Plant Startup will be governed by the Technical The revised relief (RR V 4)
Specifications (TS) to determine initiation of Specifications. Therefore, relief request RR-request did not provide corrective action for valves in flow paths which are V-4 has been revised to clarify the application additionat information not specificat ty ediressed in TS.
If the testing of a of the Technical Specifications for valves on the valves that are valve is deferred to attow plant start-up, testing which f all the ASME Section XI testing during not addressed in 15.
shall be conducted which demonstrates acceptable cold shutdown or refueling.
Therefore, the status operation of the valve prior to returning the valve to of this relief request
- service, has not thenged.
Item 9 Relief was granted from testing the vacuan breakers on Relief request RR V-11 was developed to test The licensee has (RR V-11) the relief and ADS valve discharge lines quarterly and the safety relief valve (SRV) vacuun breakers addressed the concerns during all cold shutdowns provided the vacuun breakers on a f requency determined by their function of the anomaty. No are tested at cold shutdowns when the contairment is (i.e., pressure relief and automatic further NRC action is de-inerted.
depressuritauon system or pressure relief and required.
tow-low set). The retlef request was granted provided all $RV vacuun breakers are tested at each cold shutdown. The relief request has been revised to specify testing (i.e., visual inspection erut force push test) at each cold shutdown if the drywelI is de-inerted.
k ltem Number Description from NRC SE GPC Actions as Described in April 16, 1992, Current SE and (Relief Dated Decenber 10, 1991 and June 5, 1992, IST Program submittats Remaining Actions Request)
Item 10 Interim relief was granted for a period of time to Att 6 valves are controtted with a single Response provided to (RR V 39) attow the licensee to develop a method to detect switch in the main control room. This method the NRC by Novenoer 17, individual valve degradation of the scram discharge actuates a single pilot solenoid which is not 1992.
volume vent and drain valves.
connected to RPS togic and does not result in stroke times which are comparable to those obtained during each refueling outage.
l Stroking each valve individually would require manipulating energized control circuits (RPS) which could result in a reactor scram.
Also, the licensee did not identify the required The relief request has been revised to provide the licensee has 4
closing time for the Unit 1 valves and incorrectly the correct closing time for the scram addressed the concerns described the operation of valve F011 in relief discharge volune vent and drain valves and a of this portion of the request NR V-39 description of the correct operation of valves anomaly. No further 1(2)C11-F011. A revised copy is included in NRC action is required.
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the June 5,1992, stenittet.
1 Item 11 Interim relief was granted for a period of time to System Modifications would be required to Response provided to (RR V-32 atlow the licensee to develop a method to detect install position indication. The licensee the NRC by Noventer 17, 6
and individual valve degradation of the ilP purge supply proposed to perform a study to determine if an 1992.
RR-V 40) valves and valves 2C51 F3012 and C51 f3012.
acceptable method of monitoring and detection l
degradation is available and make any necessary program revisions as a result of this study.
Item 12 valves (2)C11 HCU-115, NCU accumulator charging header Relief request RR-V-26 specified an incorrect The licensee has (RR V-26) checks, are categorized B instead of C.
ASME Section RI category for the hydraulic addressed the concerns j
control unit (HCU) accumulator charging water of the anomaly. No check valves. The retlef request has been further NRC action is revised to correctly categorlie these valves as required.
4 category C.
Item 13 Interim relief was granted to attow the licensee to these check valves may be partial stroke Response provided to (RR-V 14 investigate the use of non-intrusive diagnostic exercised during SDC mode of RHR. During a the NRC by November 17, i
and techniques to verify that the RNR injection check cold shutdown, both loops of RHR might not be 1992.
l RR-V-17) valves futt-stroke exercise open when subjected to utilized for sDC (depending on outage flow either during cold shutdowns or during refueling darat ion). Testing both valves may delay j
1 outages.
reactor starttp and increase personnel exposure. Relief requests RR-V-13 and RR V 17 l
will be revised to add justification for not i
partial stroke esercising both valves during cold shutdown. In addition, studies of alternatives to disassenbly and inspection for 4
these valves will be performed, i
s i l
1 4
Item Nunber Description from NRC SE GPC Actions as Described in April 16, 1992, Curreat SE and (Retief Dated Dececber 10, 1991 and Jtsie 5,1992, IST Program $tdeittels Remaining Actions Requast)
Item 14 Interim relief was granted to allow the licensee to In order to full stroke these valves, the Response provided to (RR V-22) develop a method of monitoring for degradation of the permissive logic must be disabled. A study the NRC by Noveeer 17, RNR heat exchanger service water outlet valves, will be performed to determine if an acceptable
- 1992, method of monitoring and detection degradation is avaltable, item 15 Interim retlef was granted to attow the licensee to since these valves do not see flow during any Response provided to (RR V-13 investigate methods to test the core spray injection normal mode of operation or shutdown conditions the NRC by Novenber 17, and check valves during cold shutdowns and refueling and the instatted test actuator is unreliable, 1992.
RR V 16) outages. If these methods are f ound to be disassenbty and inspection of one of the two ippractical, the licensee should document the reasons valves every second refueling outage is the these test methods cannot be epptoyed.
only viable testing technique to verify forward flow operability. the licensee will conduct a study of possible alternatives for disassently and inspection of these valves.
Item 16 Relief was denied to verify closure of the HPCI Items 16 and 18 concern reverse flow closure Relief already granted (RR V-30A) minipun flow line and turbine eshaust drain check testing of nicerous check valves which provide for Jockey ptrp valves by performing a reverse flow test during contairment boundary in the jockey ptrp, MPCI recirculation Line refueling outages. The licensee did not provide en and RCIC systems. Att of the stbject valves check valves in the adequate technical justification for not performing are containment isolation valves but do not Decentw e "1
1991 SE.
this testing quarterly during power operations or require Appendix J Leak rate testing because during cold shutdowns, the pipe lines are postulated to remain covered R* Met no longer with water during att accident conditions.
required for HPCI and RCIC ptro check valves The licensee revised the relief request to (f)(4)(iv).
provide additional information to sutvort their proposed testing of these valves during refueling outages.
Item 17 Relief was granted to atlow testing of the NPCI torus Item 17 concerned partial flow exercising of the licensee providad (RR-V-7 suction check valve by disasseably, inspection, and the NPCI torus suction check valves af ter additional information and manual exercising, provided the licensee develop a reassecbly. The valves are disassenbled and in the revised relief RR V-12) method to partist-stroke exercise this valve with flow inspected periodically as an alternative to request which clarified after reassenbty every refueling outage. Extension of futt flow exercising per ASMC Section XI.
that partial-stroke the testing interval can be ecceptable if att the Currently, no practical method exists to exercising is guidelines presented in Generic Letter 89 04, Position partially exercise these valves after impractical for the 2, are followed and the basis for extending the reassently.
same reasons that futt-interval is justified and docteented.
stroke exercising is inprac t ic al, j
therefore, no further NRC action is required.
1 -
Item Ntrtier Description from NRC SC GPC Actions BS Described in April 16, 1992, Current SE and (Relief Dated Deceder 10, 1991 and June 5, 1992, IST Program Submittats Remaining Actions Request)
Item 18 Relief was denied to verify closure of the RCIC See item 16.
See item 16.
(RR-V-304) minimum flow line and turbine exhaust drain check valves by performing a reverse flow closure test during refueling outages. The licensee did not provide an adequate technical justification for not performing this testing quarterly during power operations or during cold shutdowns.
Item 19 Cold shutdown justification CS-7 referenced only the The cold shutdown justification has been the concerns of the (CS 7) high pressure coolant injection (NPCI) system but revised to reference both HPCl and RCIC system anomaly have been included justification for both HPCI and reactor core valves.
addressed by the isolation cooling (RCIC) system, revision of the cold shutdown justification.
No further NRC action is required.
Item 20 The licensee was informed that all RCic system valves The licensee stated that RCIC is not required Response provided to other than those performing a containment isolation for safe shutdown of the plant and only RCIC the NRC by Novendier 17, function could be deleted from the IST program if conponents required for conteirnent isolation 1992.
credit was not taken for the operability of the system should be in the IST program. Additional in the station accident analysis. However, the NRC justification for this position will be now recommds that all appropriate RCit system valves provided by the licensee, should be included in the 1st program and tested per Section XI to the extent practical. This is because the RCIC system is designated a " safe shutdown system" and is addressed in the station 15 which specify operability and testing requirements in addition to placing limiting conditions for operation in effect in the event the system becomes unavailable.
Item 21 Relief was denied for verifying closure of the RWCU This item concerned reverse flow closure Relief no longer (RR V-18) return header check valves on a refueling outage testing of the Unit 1 RWCU system return check required (f)(4)(iv).
frequency. The licensee did not provided an ade<pate valves at cold shutdown. Retlef request technical justification for not exercising these RR V 18 has been revised to provide additional valves during cold shutdowns. A review of the system justification for testing these valves at P&lD shownf that the necessary test connections and refueling only, isolation valves are instatted. -
[
Iteet Nuter Description f rom NRC st GPC Actions as Described in April 16, 1992, Current SC and (Retief Dated Decentier 10, 1991 and June 5,1992,1st Program sutnittats Remaining Actions Request)
Item 22 Interim relief was granted to at tow the licensee to These valves have no indicating lights or Response provided to (RR V-20) develop a method of monitoring valve degradation in position control switches. stroke timing is the NRC by Nove'$er 17, the ptep room cooter atspty lines for the RNR, HPCI, accomplished by observing stem movement ervi
- 1992, and core sprey pape, and for the dieset generators.
verifying the time is less than a pre-determined value. The licensee will conduct a study to determine if other acceptable methods of monitoring and detecting degradation are avettable.
in addition, the licensee categorized these valves in This relief request specified en incorrect AsME The licensee has relief request RR-V-20 es C however, the proper section NI category for the plant service water ediressed the concerns categorization is B.
ECCs room cooter air operated valves. The of this portion of the relief request has been revised to correctly enomaly. No further categorite these volves as category 8.
NRC sction is required.
Item 23 Relief was granted to senple disasseable and inspect There is no suitable instat ted instrunentation Response provided to (RR V-19) the HPCI end RMR prp cooler outlet check volves in sveitable to determine if the CV strokes open the NRC by Novenber 17, accordance with Generic Letter 89 04, Position 2, when the associated ptmp room cooter is 1992.
provided that the velves are partiet-stroke exercised operated. The licensee will perf orm a stisfy of with flow following reassen6ty but prior to returning alternettves to disassenbty and inspection for them to service. In addition, the licensee was these valves, advised to investigate the use of non intrusive diagnostic techniques to verify these valves full-stroke exercise open when stbjected to partial flow.
Item 24 Interim relief was granted for one year, or until the Flow elements installed downstream of the Response provided to (RR V-41) next refueling outage, to ottow the licensee to subject check valves were used for pre op flow the NRC by Novenber 17, develop or verify a method of futt stroke exercising betencing but have not been maintained. D/G 1992.
the diesel generator service water outlet check power levels achieved during testing should be volves.
odequate to exercise the stbject check valves.
The Licensee will perform a study of D/G power levels achieved during refueling outage testing to show that moitimte required accident flow through the st.bject check valves will be achieved.
Item 25 Relief was denied for verifying reverse flow closure Relief req;est RR V-25 did not cteerly describe The testing method is (RR-V-25) of the service water punp discharge check valves the frew;ency of testing for the plant service in accordance with the during normal equipment rotetton.
water prp discharge check valves. The present Code requirements. No testing is in coppliance with the AsME Code.
further NRC action is Relief request RR-V 25 has been revised to more required.
clearly explain the actual testing inplemented.
.+
Item Ntober Description from NRC SE GPC Actions as Described in April 16, 1992, Current SE and (Retief Dated Deceeber 10, 1991 and Jme 5,1992, IST Program Sutsnittats Remaining Actions Request)
Item 26 Interim relief was granted for one year, or until the the subject solenoid valves are passive Response provided to (RR-V-31) next refueling outage, to allow the licensee a period containmant isolation valves which are only the NRC by Noveneer 17, of time to develop a means of monitoring the condition opened to exercise the torus to drywell vacum 1992.
of the torua to drywett vectun breaker air supply breakers per NRC request. Since position solenoid valves.
Indication is not available for these 50V's and they have no active safety fmetion, the licensee stated that the testing described in RR-V-31 should be appropriate.
Item 27 The licensee f ailed to provide the necessary technical CS-4 has been revised to pre, vide additional the justification (CS-4) information to evaluate cold shutdown justification justification for testing at cold shutdown.
provided is sufficient.
CS-4.
Therefore the licensee was to either esercise No further action is the turbine building service surply water valves necessary.
quarterly or provide information that clearly explains why these valves either cannot or should not be esercised during power operation.
Item 2F Note 10 of the IST program stated that check valves The Licensee revised note 10 to provide The licensee has will be disassecbled on a rotating basis per Generic clarification. Specific relief requests will addressed the concerns Letter 89 04. but gave no further explanation of the be sutsnitted f or any check valve disassenbled of the anomaty, disassently and inspection program, it did not appear for IST that cannot be partially esercised with Additional relief that the licensee made provisions for esercising the flow af ter reassenbty. Any additional relief requests may be valves identified for disassenbly and inspection with requests will be subnitted within 6 months of necessary.
flow following reasseably.
receipt of a response from the NRC.
Item 29 in the second 10 year program submitted by letter The licensee submitted relief request RR-V 21 Provisional relief (RR-v 21) dated August 20, 1990, the licensee withdrew relief which proposes to verify valve closure granted (f)(6)(1).
request RR V 21 and stated in note 10 that the core capability by the use of disassenbty because spray pop mininue flow line check valves will be verification by flow or pressure measurement is disassenbted on a rotating basis in accordance with not practical.
Generic Letter 89-04, Position 2.
The licensee was to investigate the use of non-intrusive test techniques to demonstrate that these valves close upon cessation or reversal of flow.
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