CP-201300788, Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (Order No. EA-12-051), Response to Request for Additional Information
| ML13193A014 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 07/03/2013 |
| From: | Flores R, Madden F Luminant Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| CP-201300788, EA-12-051, TXX-13103 | |
| Download: ML13193A014 (25) | |
Text
Rafael Flores Luminant Power Senior Vice President P 0 Box 1002
& Chief Nuclear Officer 6322 North FM 56 Lum inant Rafael.Flores@Luminant.com Glen Rose, TX 76043 T 254 897 5550 C 817 559 0403 F 254 897 6652 CP-201300788 TXX-13103 10 CFR 2.202 July 3, 2013 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-001
SUBJECT:
COMANCHE PEAK NUCLEAR POWER PLANT DOCKET NOS. 50-445 AND 50-446 OVERALL INTEGRATED PLAN IN RESPONSE TO MARCH 12,2012 COMMISSION ORDER MODIFYING LICENSES WITH REGARD TO RELIABLE SPENT FUEL POOL INSTRUMENTATION (ORDER NUMBER EA-12-051), RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION
REFERENCES:
- 1.
NRC Order Number EA-12-051, "Issuance of Order To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation", dated March 12, 2012
- 2.
Luminant Generation Company LLC's Initial Status Report in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051) dated October 25, 2012
- 3.
Luminant Generation Company LLC's Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation (Order Number EA-12-051) dated February 28, 2013
- 4.
NRC Letter from Balwant Singal to Rafael Flores, "Request for Additional Information RE: Overall Integrated Plan in Response to Order EA-12-051, "Reliable Spent Fuel Pool Instrumentation", dated June 7, 2013
Dear Sir or Madam:
On March 12, 2012, the Nuclear Regulatory Commission ("NRC" or "Commission") issued an order (Reference 1) to Luminant Generation Company LLC (Luminant). Reference 1 was immediately effective and directs Luminant to have a reliable indication of the water level in associated spent fuel storage pools capable of supporting identification of specified levels in the pool water by trained personnel. Specific requirements are outlined in Attachment 2 of Reference 1.
Reference 1 required submission of an initial status report 60 days following issuance of final Interim Staff Guidance (ISG) and an Overall Integrated Plan by February 28, 2013. Luminant provided those responses in References 2 and 3 respectively.
A member of the STARS Alliance Callaway. Comanche Peak. Diablo Canyon. Palo Verde San Onofre. South Texas Project Wolf Creek
U. S. Nuclear Regulatory Commission TXX-13103 Page 2 07/03/2013 Reference 4 transmitted and requested Luminant's response to eleven Requests for Additional Information (RAIs) with a requested response by June 21, 2011. Following several communication's between Luminant and the Staff;,the response date was revised to July 5, 2013 in arn email dited Juhe 14, 2013.
The purpose of this letter is to provide Luminant's response to the RAIs requested in Reference 4.
Responses are contained in the Attachment to this letter.
This letter contains no new regulatory commitments.
If there are any questions regarding this plan, please contact Mr. Dennis Buschbaum at (254) 897-5851 or dennis.buschbaum@luminant.com.
I state under penalty of perjury that the foregoing is true and correct. Executed on July 3, 2013.
Sincerely, Luminant Generation Company LLC Rafael Flores By:
/,FredW. Madden Director, Oversight & Regulatory Affaiirs
Attachment:
Response to Request for Additional Information, Overall Integrated Plan in response to the Commission Order Modifying Licenses With Regard to Requirements for Reliable Spent Fuel Instrumentation (Order Number EA "
051) Comanche Peak Nuclear Power Plant Units 1 & 2, Docket Numbers 50-445 and 50-446 c -
E. J. Leeds, Director, Office of Nuclear Reactor Regulation A. T. Howell, Region IV B. K. Singal, NRR Resident Inspectors, Comanche Peak
Attachment to TXX-13103 Page 1 of 23 REQULUTFORADDIIOALWIN HR/M![N OVERALL INTEGRATED PLAN IN RESPNSE-3O THE COM.ASI*,ON ORDER MODIFYIN UCFIE WTREGAHRD TO BEMIM§M!ENTS FOBEUW. SPENT IUM..
09.pO I
QNSTR MENTTIN RER02 NUMBER E4J.*A
.1 COMANCHE PEAK NUCLEAR POWER PLANT. UNITS 1 & 2'.
DOKET UMBE W
AND MR RAWI Issue:
The 0IP states In part, that I. Level adequate t support operaton of the norma fuel pool cooling syltem -
Indicated level on either the primary or backup instrument channel of 22 feet 1.25 Inches above the top of the fuel storage racks plus the accuracy of the SFP level Instrument, which is to be determined. This level aligns with the LO-LO level process setpolnt that trips the fuel cooling pump as described in Comanche Peak FInal Safety Analysls Report (FSAR) Section 9.1.3.2 (Reference 5).
- 2. Lvel alequate to provide substanttall rdiaton shielding for a pme n standing on the spent fuel pool operating deck - Indicated level on either the primary or backup instrument channel of greater than 10 feet (t 1 foot) above the top of the fuel storage racks based on Reference 2 and 3. This monitoring level ensures there is an adequate level to provide substantial radiation shielding for a person standing on the spent fuel pool operating deck.
- 3. Level where fuel remains covered - Indicated level on either the primary
- r, backup instrument channel of greater than I foot above the top of the fuel storage racks lus the accuracy of the SFP level instrument channel, which is to be determined. This monitoring level assures that there Is adequate water level above the stored fuel seated in the rack.
In addition, uinder section for "Instruments," the OIP states, In part, that The primary and backup Instrument channels wil provide continuous level indication over a range of 23 feet 9.25 Inches, from 12 Inches above the top of the fuel storage racks (plant level 835 feet 2.75 Inches) to the high pool level elevation (plant elevation 859 feet).-
Attachment to TXX-13103 Page 2 of 23 Please provide the following:
a) The specific functional reasons for Identification of the elevations within the SFP as levels 1, 2 and 3. For level 1, specify how the Identified location represents the HIGHER of the two points described In the NE1.12-02 guidance for this level.
b) A clearly labeled sketch depicting the elevation view of the proposed typical mounting arrangement for the. portions of instrument channel consisting of permanent measurement channel equipment (e.g., fixed level sensors and/or stilling wells, and mounting brackets). Indicate on this sketch the datum values representing Level 1, Level 2, and Level 3 as well as the top of the fuel. Indicate on this sketch the portion of the level sensor measurement range that is sensitive to measurement of the fuel pool level, with respect to the Level 1, Level 2, and Level 3 datum points.
Comanche Peak Response:
a)
Level 1, the level that is adequate to support operation of the normal fuel pool cooling system, Is defined In NEI 12-02 as the higher of the following two points:
" The level at which reliable suction loss occurs due to uncovering of the coolant Inlet pipe, weir or vacuum breaker (depending on the design), or
" The level at which the water height, assumingsaturatd conditions, above the centerline of the cooling pump suction provides the required net positive suction head specified by the pump manufacturer or engineerng analysis Comanche Peak designated Level I to be EL. 656 feet 4 Inches (22 feeti, 1.25 Inches above the top of the fuel racks). This level coresponds to the L04LO level process setpoint that trips the fuel pool cooling pump as described In Comanche Peak Final Safety Analysis Report (FSAR) Section 9.1.3.2. The LO-LO eell process set point Is selected to ensure that the pump will trip prior to a point where a void will occur in the suction Oines. Analysis has demonstrated that there is adequate NPSH for pump operation at saturated conditions for water at plant elevation 856 feet The LO-LO level setpoint Is thus the higher of the two pump-limiting condtlions specified In NEI 12-02.
Attachment to TXX-13103 Page 3 of 23 As described In NEI 12-02, Level 2 is the level that Is adequate to provide substantial radiation shielding for a person standing on the spent fuel pool operating deck. It represents the range of water level where any necessary operations In the vicinity of the spent fuel pool can be completed without significant dose consequences from direct gamma radiation from the stored spent fuel. Level 2 Is based on either of the following:
10 feet (+/- I foot) above the highest point of any fuel rack seated In the spent fuel pools, or that level, which provides adequate radiation shielding to protect personnel performing local operations in the vicinity of the pool to Install or maintain SFP instrument channel components, based on either plant-specific or appropriate generic shielding calculations, considering the emergency conditions that may apply at the time. Additional guidance can be found In EPA-400 (Reference 4), USNRC Regulatory Guide 1.13 (Reference 5) and ANSI/ANS-57.2-1983 (Reference 6).
Comanche Peak designated as Level 2 the water level 10 feet (* 1.0 foot) above the top of the fuel racks, consistent with the first option above.
Level 3 NEI 12-02 describes Level 3 as the level where fuel remains covered and actions to Implement make-up water addition should no longer be deferred. Level 3 corresponds nominally (I.e., +/- 1 foot) to the highest point of any fuel rack seated In the spent fuel pool. Level 3 is defined In this manner to provide the maximum range of Iformation to operators, decision makers and emergency response personnel.
Comanche Peak designated as Level 3 the water level greater than I foot above the top of the fuel storage racks plus the accuracy of the 8FP level Instrument channel, which is to be determined. Designation of this level as Level 3 Is conservative; Its selection assures that the fuel will remain covered, and at that point there would be no functional or operational reason to defer actlon to Implement the addition of make-up water to the pool.
Attachment to TXX-13103 Page 4 of 23 Response to RAI Item Ib:
The sketch below contains Infommation requested In RAI lb (Instrument uncertainty, which Is to be determined, Is not inclued In the elwation values for Levels I and 3).
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Attachment to TXX-13103 Page 5 of 23
RAI-2
Issue:,
- i.
The OIP states in part, "The preliminry'locations of thepdmar and backup Instrument
.'Ing components are at.the plant southeast and south*est corners qf I-northeasftand nptthiest comers of SFP 2 (X-02)..
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- ~t*i
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The desilgi for inisiallation will Include Ohysfcal separation of the two se~n, eepaýatq extens*on cAbles from the electronics to thi sensors, routing all cables In separate conduft trays, separ UPS power supplied from jlferen4 ac sources, and seismlly qualified poupting vphysial separtion of both the level sensing and Indications.
Mlountig Brackets: The final location of the prtmaie and VARWp y
Montn heprmryan bckpsystemianngraks be detqrminedby the detailed design Witonsidet of power avalllabl sparatlon requiirments to~protect against missiles.
Electrnics:1the level sensing electronics for.botihrimary and backup systems a.. located In the shared building, compliant with Reference2aend Referer
.for sepa=98 S
a.
accessibility. The primary system Indicator wil be located In the vicinity of the -
- 6om. The backup system Indications will be located In accessible locations.
Provide responses to the following:
a) A clearly labeled sketch or marked-up plant drawing of the plan view of the SPP area, depicting the SFP inside dimensions, the planned locations/ placement of the primary and back-up SFP level sensor and mounting brackets, and the proposed routing of the cables that will extend from the sensors toward the location of the read-out/display device.
b) In the event any part of this information is not available with the submittal of your response to this RAI, provide the date this Information will be submitted.
Comanche Peak Response:
Below are excerpts from plant drawings being used as sketches that depict the conceptual locations of the two permanently mounted level probes within the SPP area and the cable routing to locte the eleotronlcs to a non-harsh environment outside the SFP area.
The level transmitter electronics will be located In the Auxiliary Building EL 852W0", which Is separated from the SFP area by pressure boundary doors. The level transmitters located In the Auxiliary Building have a local display, although the credited display units will be located in the main control room on the east wail, just off the control board area. The final locatiors of the channel components and cable routig wil be determined during the design phase, anticipated to be completed by December 31, 2013.
Attachment to TXX-13103 Page 6 of 23
Attachment to TXX-13103 Page 7 of 23
Attachment to TXX-13103 Page 8 of 23
Attachment to TXX-13103 Page 9 of 23 The Inside dimensions of the 2 SFPs are 300" by 40'-3". Reference excerpt from plant drawing below.
I b) Not Opiable.
Attachment to TXX-13103 Page 10 of 23 RA-3 Issue:
The OIP states, "The mounting of both primary and backup system will be installed to maintain Its integrity during and following a design bases seismic event. All locations will be reviewed for two-over-one seismic interference."
Provide responses to the following:
a) The design criteria that will be used to estimate the total loading on the mounting device(s), Including static weight loads and dynamic loads. Describe the methodology that will be used to estimate the total loading, Inclusive of design basis maximum seismic loads and the hydrodynamic loads that could result from pool sloshing or other effects that could accompany such seismic forces.
b) A description of the manner In which the level sensor (and stilling well, If appropriate) will be attached to the refueling floor and/or other support structures for each planned point of attachment of the probe assembly. Indicate in a schematic the portions of the level sensor that will serve as points of attachment for mechanical/mounting or electrical connections.
c) A description of the manner by which the mechanical connections will attach the level instrument to permanent SFP structures so as to support the level sensor assembly.
Comanche Peak Response:
a) The mounting bracket for the sensing probe will be designed according to the plant design basis for SSE seismic hazard curve at the appropriate plant elevation. Loads that will be considered in the evaluation of the.bracket and Its mounting are: 1-Static loads Including the dead weight of the mounting bracket In addition to the weight of the level sensing Instruments and cabling; 2-Dynamic loads Including the seismic load due to excitation of the dead weight of the system In addition to the hydrodynamic effects (If credible considering the geometry and the flexibility of the sensin probe and the water sloshing height) resulting from the excitation of the spent fuel pool water. A response spectra analysis will be performed for the seismic evaluation of the mounting bracket using a Finite Element Analysis (FEA) software and using floor response spectrum at Elevation 8W in the Fuel Building (i.e. mounting floor elation). Damping values will be acoording to the Safe Shutdown Earthquake (SSE) and consistent with the design basis of the station. The material properties that will be used for the bracket and its mounting will take Into considemrton the environmental conditions In the Spent Fuel Pool area following an SSE. Hydrodynamic effects on the mounting bracket will be evaluated using TID-7024 (Nuclear Reactors and Earthquakes, dated 1963). Plant acceptance criteria and applicable codes will be used for the design of the bracket and its anchorage.
b) The typical schematic below details the pedestal that will attach to the pool deck. The bracket will be attached to the pool deck using Installed anchors that will be designed
Attachment to TXX-13103 Page 11 of 23 according to the plant exting speciftiton for design of Concrete anchors. The pedestal will be ajustmed to the helgt of the poolside curb to enmure the SWP bracket extends over the pool hrizontaly level.
am" N=U
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SECiON A6 A The probe a*tcsm to he bra" via a 1 T
ih th dbd connec*n. The scherra*c below detailse tovtcW portion of t bradck where th probe wit Mred into th bradat Non-movW* connetios of peft wllw be welder.ensions wme nomirnal nd may be ajust for selnc qu*_.lioston and fina delivery. It Is undetrined I a sUng well wil be Wead. Te stn well opo will be deemined drn the desin phass,, anipe o be m plete by Deceber 31, 2013& If a stilling well Is kitalled, It will be welled to th lower porWn of to bracket, sumni te senso probe cal.
Attachment to TXX-13103 Page 12 of 23 c) The a0tacet of the senlsm cl fe "
to the poo dock wI be trough permanently el ed aoncho.
Withe o
Wh mianelk y Is*tue ths brac"t t
pedsta wit be secured to the pool"id dock with adequat. washers and bob.
Attachment to TXX-13103 Page 13 of 23 RAJ-4 Issue:
The OIP states In part, "The instrument channel reliability shall be demonstrated via an appropriate combination of design, analyses, operating experience, and/or testing of channel components for the following sets of parameters...
The normal operational, event and post-event for temperature, humidity, and radiation will be addressed for no fewer than seven days post-event or until off-site resources can be deployed by mitigating strategies resulting from the NRC Issued Order EA-12-049, "Issuance of Order to Modify Licenses with Regard to Requirements for Mitigating Strategies for. Beyond Design-Basis External Events."
The instrument channel rellability will be demonstrated via an appropriate combination of design, analysis, operating experience, and/or testing of channel components for the effects of shock and vibration. Demonstration of shock and vibration will be consistent with the guidelines in Reference 2 and Reference 3."
Provide responses to the following:
a) A description of the specific method or combination of methods you intend to apply to demonstrate the reliability of the permanently Installed equipment under beyond-design-basis ambient temperature, humidity, shock, vibration, and radiation conditions.
b) A description of the testing and/or analyses that wiN be conducted to provide assurance that the equipment will perform reliably under the worst-case credible design basis loading at the location where the equipment will be mounted. Include a dlscusslon of this seismic reliability demonstration as it applies to a) the level sensor mounted in the SFP area, and b) any control boxes, electronims, or read-out and re-transmitting devices that will be employed to convey the level information from the level sensor to the plant operators or emergency responders.
c) A description of the specific method or combinaton of methods that will be used to confirm the reliability of the permanently Installed equipment following seismic conditions to maintain its required accuracy.
Comanche Peak Response:
item a)
Demonstration of the reliability of the permanently installed SFP1S equipment under the beyond-design-basis conditions will be by design, analysis, operating experience and testln by the system vendor and the equipment manufacturer(s), as described below for each of the Identified conditions.
Temperature and Humidity
Attachment to TXX-13103 Page 14 of 23 SFPIS materials and components were selected and specified by design to meet or exceed the temperature and humidity requirements of 212 OF and 100% humidity In the SFP area, and design basis conditions for locations of sensor and system electronics. Design is supplemented by tests of system components as shown below.
y!stem Component aB9le for Demonstration Sensor Probe By design. Stainless steel cable probe is inherently tolerant of the effects of the specified temperature and humidity.
Sensor Bracket By design and analysis. Stainless steel bracket Is inherently tolerant of the effects of the specified temperature and humidity.
Sensor Coupler By design. The coupler Is primarily stainless steel, and is specifically designed by the manufacturer for high temperature and humidity
_alicatlons.
Coaxial Cable By design and testing. Selected by design for conditions; tested for performance at 212 OF, saturated steam.
Sensor Electronics By design. Sensor electronics design temperature exceeds requirements for the sensor electronics mounting.locations.
System Electronics and By design and testing. Component design temperature exceeds Display requirements for equipment mounting locations; tested for performance under conditions of temperature and humidity coying.
Shock and Vibration Ali components located within the spent fuel pool are passive components, Inherently resistant to shock and vibration loadings. These Include the stainless steel sensor cable probe, sensor bracket, coupler and Interconnecting cable.
Active electronic components, located outside the spent fuel pool area, are permanently and rigidly attached to seismic racks or structural walls, and are not subject to shock and vibration loadings. However, assurance of reliability under conditions of shock and vibration Is supported by manufacturer operating experience, which Includes use of components in high vibration Installations, such as compressed air systems and transpotato Industries.
Radiation Components subject to significant radiation under beyond design basis conditions are those In the spent fuel pool area. These Include the sensor probe, bracket, coupler and Interconnecting cable. The sensor probe and bracket are stainless steel and will not be affected by the anticipated radiation. The coupler and cable are selected by design for the beyond design basis radiation service. Supplemental radlation testing of the Interconnecting cable will be completed to dor operation for more than one week with spent fuel pool water at level 3.
tem b)
The sensor cable probe and supporting bracket are functonally, passive components. Analysis will be used to demonstrate they will maintain their structural integrity and design configuration and to establish their reliability. The coupler and Interconnecting cable are also passive
Attachment to TXX-13103 Page 15 of 23 components; however, they will be included In the seismic testing of the sensor electronics. All active system components, including sensor electronics, system electronics, batteries, display and enclosures will be seismically tested based on rigid mounting conditions. Testing is tri-axial, using random multi-frequency Inputs, In accordance with IEEE 344 - 2004. Analyses and testing will envelope the conditions at equipment mounting locations resulting from the design basis ma)dmum ground motion.
Item C)
All components except for the stainless steel sensor cable probe and the stainless steel bracket will be seismically tested In a rigidly-mounted condition equivalent to their as-Installed condition.
The cable probe and bracket are passive components for which maintenance of structural or physical integrity is the only requirement. The active components of the spent fuel pool Instrumentation system will be functionally tested before and after seismic simulation. Water level Inputs to the system will be simulated by grounding the system probe at selected, repeatable positions. Comparison of system output will be made both to pre-test results and to the measured position of the cable probe Input.
Attachment to TXX-13103 Page 16 of 23
RAI-5
Issue:
The OIP states, "The backup Instrument system will be redundant to and independent of the primary instrument system. Independence of the two systems include: location, mounting, power sources, power and signal wiring, and indications, to prevent any failure of one system from affecting the other system."
Provide responses to the following:
a) A description of how the two channels of the proposed level measurement system meet this requirement so that the potential for a common cause event to adversely affect both channels is precluded.
b) Further information on how each level measurement system, consisting of level sensor electronics, cabling, and readout devices will be designed and installed to address Independence through the application and selection of Independent power sources, the use of physical and spatial separation, independence of signals sent to the location(s) of the readout devices, and the independence of the displays.
Comanche Peak Response:
a) Within the SFP area, the brackets will be mounted as close to the Southeast (primary sensor) and Southwest (back-up sensor) corners of the X-01 pool and the Northeast (primary sensor) and Northwest (back-up sensor) corners of the X-02 pool, as permanent plant structures allow. Placing the brackets and probes in the comers allows for natural protection from a single event or missile from disabling both systems. The cabling within the SFP area will be routed In separate hard-pipe conduit. All conduit routing and location of system components will be selected such that there will not be any seismic 2 over I hazard.
b) Each system will be Installed using oompletely Independent cabling structures, including routing of the interconnecting cable within the SFP area in separate hard-pipe conduits.
Power sources will be routed to the electronics enclosures from electriclly separated sources ensuring the loss of one train or bus will not disable both channels. The system displays will be installed In separate qualified NEMA 4X or better enclosures, with the primary and back-up display in the control room envelope. Primary and backup systems will be completely Independent of each other, having no shared components.
Attachment to TXX-13103 Page 17 of 23
RAI-6
The OIP states, In part, that An AC [alternating current] source will be selected for each system's 24-Vdc [Volts direct current] UPS, with power cables, with power cables routed separately through edsting or new tray / conduit and presentations.
Both channels will be powered by Independent batteries following a loss-of-AC power. The minimum battery life will be 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> battery life is sufficient amount of time for an alternate source of power to be provided by the plant-specific procedures to address Reference
- 6. Each channel will include an externally accessible bulkhead connector and a transfer switch for connection of an alternate power source.
Please provide the following:
a) A description of the electrical AC power sources and capacities for the primary and backup channels.
b) The document and/or the procedure that addresses the actions 4following a loss of-AC power."
c) If the level measurement channels are to be powered through a battery system (either directly or through an UPS, please provide the design criteria that will be applied to size the battery in a manner that ensures, with margin, that the channel will be available to run reliably and continuously following the onset of the beyond-design-basis event for the minimum duration needed, consistent with the plant FLEX Program plans.
Comanche Peak Response:
a) A description of the electrical AC power sources and capacities for the primary and backup channels will be developed as part of the detailed design and more information will be provided by November 30,2013.
b) With respect to operation and use of the SFPIS, no Immediate action Is required In the event of a loss of AC power. The SFPIS includes a battery-baked, unnterruptible power supply, with battery capacity to power the system for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The overall procedural response to a loss of AC power Is governed by the FLEX Support Guidelines which are being developed as a part of the response to NRC Order EA-12-049.
c) Battery sizing Is In accordance with standard IEEE 488-2010. Design criteria applied are: Continuous system operation for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> following lose of ac power. Calculation of system power consumption is based on the specified values listed In component manufacturer specifications. A 10% capacity margin Is added to battery sizing calculations, following guidelines of IEEE 485-2010, Section 6.22. The time to restore AC power to the primary and backup channels will be within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, and will be established In the FLEX Support Guidelines.
Attachment to TXX-13103 Page 18 of 23
RAI-7
The OIP states, in part, that Instrument channels will be designed such that they will maintain their specified accuracy without recalibration following a power interruption or change in power source. The accuracy will be within the resolution requirements of Reference 2, Figure 1. The instrument accuracy will be sufficient to allow personnel using plant procedures to determine when the water level reaches levels 1, 2, and 3 without conflicting or ambiguous indication.
Please provide the following:
a) An estimate of the expected Instrument channel accuracy performance under both (1) normal SFP level conditions (approximately level 1 or higher) and (2) at the beyond-design-basis conditions (i.e., radiation, temperature, humidity, post-seismic and post-shock conditions) that would be present if the SFP level were at the level 2 and level 3 datum points.
b) A description of the methodology that will be used for determining the maximum allowed deviation from the instrument channel design accuracy that will be employed under normal operating conditions as an acceptance criterion for a calibration procedure to flag to operators and to technicians that the channel requires adjustment to within the normal condition design accuracy.
Comanche Peak Response:
a) The instrument channel accuracy will be established during the design phase. An estimate of the expected instrument channel accuracy under normal and beyond-design-basis conditions will be provided by November 30, 2013.
b) The calibration procedure, and the methodology and basis for establishing both the criteria Indicating the need for recalibration, and the acceptance criterion to be used with the procedure, will be established during the design phase. The methodology for defining these criteria will be provided by November 30, 2013.
Attachment to TXX-13103 Page 19 of 23 RAI-S The OIP states, in part, that Instrument channel design will provide for routine testing and calibration consistent with Reference 2 and Reference 3.
Please provide the following:
c) A description of the capability and provisions the proposed level sensing equipment will have to enable periodic testing and calibration, Including how this capability enables the equipment to be tested in-situ.
d) A description of how such testing and calibration will enable the conduct of regular channel checks of each independent channel against the other, and against any other permanently-nstalled SPF level Instrumentation.
e) A description how functional checks will be performed, and the frequency at which they will be conducted. Please descrbe how calibration tests will be performed, and the frequency at which they will be conducted. Also, a discussion as to how these surveillances will be Incorporated Into the plant surveillance program.
f) A description what preventative maintenance tasks are required to be performed during normal operation, and the planned surveillance Interval that is necessary to ensure that the channels are fully conditioned to accurately and reliably perform their functions when needed.
Comanche Peak Response:
c) Details of the capabilities and provisions of the level Instrumentation for periodic calibration and testing will be established during the design phase. A description of these features and the way they will support In-situ testing will be provided November 30,2013.
d) A description of how the defined testing and calibration will enable th. conduct of regular channel checks of each independent channel against the other, and against any other permanently-installed SPF level Instrumentation will be provided November 30, 2013.
e) Details of functional checks and Instrument channel calibrations will be determined during the design phase. A description of how functional checks and calibration tests will be performed, and the frequency at which they will be conducted, will be provided November 30, 2013. An explanation of how these surveillances will be Incorporated Into the plant surveillance program will be Included.
Attachment to TXX-13103 Page 20 of 23 f) The preventative maintenance tasks required to be performed during normal operation, and the planned surveillance Intervals will be determined during the design phase. A description of these tasks and intervals will be provided November 30, 2013.
Attachment to TXX-13103 Page 21 of 23
RAI-9
The OIP states, In part, that The primary system indicator will be located In the vicinity of the control room. The backup system indicators will be located in accessible locations. The locations will allow for reading of the indicators following an event. The display will provide continuous Indication of the SFP water level and will be consistent with the guidelines of Reference 2 and Reference 3.
Provide responses to the following:
a) The specific location for the primary and backup instrument channel display.
b) If the primary or backup display location Is other than the main control room, then provide justification for prompt accessibility to displays Including primary and alternate route evaluation, habitability at display location(s), continual resource availability for personnel responsible to promptly read displays, and provisions for communications with decision makers for the various SFP drain down scenarios and external events.
c) The reasons justifying why the locations selected enable the Information from these instruments to be considered "promptly accessible" to various drain-down scenarios and external events.
Comanche Peak Response:
a) The recognized primary and backup displays, pursuant to NRC Order EA-12-051 will be In the Control Room, EL-630'-(T, on the approximate centerline of the East wall for each Unit.
b) The primary and backup displays for both units will be In the main control room.
c) During all drain-down scenarios and external events the main control room will be manned. With the displays Inside the main control room they are considered "promptly accessibleW.
Attachment to TXX-13103 Page 22 of 23 4.0 Pro-ram Ego 4.1 Procedures The OIP states, in part, that Procedures will be developed using guidelines and vendor instructions to address the maintenance, operation, and abnormal response issues associated with the new SFP level Instrumentation.
FLEX Support Guidelines will address strategy to ensure SFP water makeup Is initiated at an appropriate time consistent with implementation of NEI 12-06,
'Diverse and Rexible Coping Strategies (FLEX) Implementation Guide."
(Reference 8).
RAI-10
Please provide a description of the standards, guidelines and/or criteria that will be utilized to develop procedures for Inspection, maintenance, repair, operation, abnormal response, and administrative controls associated with the SFP level instrumentation, as well as storage and installation of portable Instruments.
Comanche Peak Response:
Appropriate quality assurance measures will be selected for spent fuel pool kvl Instrumentation (SFPLI) required by the order (EA-12-051) consistent with Appendix A-1 of NEI 12-2, similar to those imposed by Regulatory Guide 1.155. Site procedures for Inspection, maintenance, repair, operation, abnormal response and administrative controls for the SFP level Instrumentation will be developed In accordance with Comanche Peak procedure controls, using the vendor technical manual and other documenaton. The vendor technical manual and documentation will include principles of operation, Inspection and maintenance recommendations, drawings and technical documentation, individual component manufacturer manuals and documentation and recommended spare parts. Additional procedures for abnormal response will be developed In conjunction with FLEX Implementatim. As these procedures are developed, additional deails wil be provided In 6 month updates. These procedures are expected to be complete by June 30, 2014.
Attadhment to TXX-13103 Page 23 of 23 RAM-1 The OIP states, in part, that Processes will be established and maintained for scheduling and Implementing necessary testing and calibration of the primary and backup SFP level instrument channels to maintain the instrument channels at the design accuracy. Testing and calibration of the Instrumentation will be consistent with vendor recommendations and other documented basis as appropriate.
Please provide the following:
a) Further information describing the maintenance and testing program the licensee will establish and implement to ensure that regular testing and calibration is performed and verified by inspection and audit to demonstrate conformance with design and system readiness requirements. Please include a description of your plans for ensuring that necessary channel checks, functional tests, periodic calibration, and maintenance will be conducted for the level measurement system and its supporting equipment.
b) A description of how the guidance in NEI 12-02 Section 4.3 regarding compensatory actions for one or both non-functoning channels will be addressed. Please Include a description of what compensatory actions are planned in the event that one of the instrument channels cannot be restored to functional status within 90 days.
Comanche Peak Response:
a) Comanche Peak will establish and implement procedures for control and oversight of SFPIS maintenance and testing. The new procedure(s) will Include requirements for all necessary tests to be performed, frequency of testing, acceptance criteria, and requirements for Inspection and audit of test performance and results. As these procedures are developed Information will be provided to the NRC In 6 month updates.
These procedures are expected to be complete by June 30,2014.
b) Comanche Peak will Implement measures to minimize the possibility of either the primary or backup channel being out of service for any extended period. Sufficient spares components and materials will be maintined to be able to repair or replace defective components in a short time. Comanche Peak will follow the NEI 12-02 guidance with regard to time during which one or more channels may be out of service, including compensatory actions. As details are developed infomati will be provided to the NRC In 6 month updates. Final details will be provided by June 30,2014.