NLS2013091, Response to Request for Additional Information Regarding Overall Integrated Plan for Reliable Spent Fuel Pool Instrumentation (Order EA-12-051)
| ML13294A027 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 10/14/2013 |
| From: | Limpias O Nebraska Public Power District (NPPD) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| EA-12-051, NLS2013091 | |
| Download: ML13294A027 (7) | |
Text
H Nebraska Public Power District Always there when you need us NLS2013091 October 14, 2013 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001
Subject:
Response to Request for Additional Information Regarding Overall Integrated Plan for Reliable Spent Fuel Pool Instrumentation (Order EA- 12-05 1)
Cooper Nuclear Station, Docket No. 50-298, DPR-46
References:
I. NRC Order Number EA- 12-051, Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation,dated March 12, 2012
- 2. NPPD Letter to NRC, Overall IntegratedPlan in Response to March 12, 2012, Commission Order Modifying Licenses with Regard to Reliable Spent Fuel Pool Instrumentation (OrderNumber EA-12-051), dated February 28, 2013 (NLS2013026)
- 3. Email from Lynnea Wilkins, NRC, to David Van Der Kamp, NPPD, RAIfor CooperRe: Reliable Spent Fuel Pool InstrumentationOrder Response (OverallIntegratedPlan) (MF0971), dated September 12, 2013
Dear Sir or Madam:
On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued an Order for Reliable Spent Fuel Pool Instrumentation (SFPI) (Reference 1) to Nebraska Public Power District (NPPD). Reference I required submission of a SFPI Overall Integrated Plan (OIP) for Cooper Nuclear Station (CNS) which was provided by Reference 2. In Reference 3, the NRC issued a request for information (RAI) regarding the SFPI OIP submitted in Reference 2.
The attachment to this letter provides NPPD's response to Reference 3. The NRC indicated in Reference 3 that if requested information is not available at the time of submittal, NPPD is to provide the date the information will be submitted. NPPD has started the design phase for the SFPI OIP and expects to complete the final design by July 2014. Based on this schedule, the RAIs cannot be fully answered at this time. The requested information will be provided in the August 2014, six-month status update, or sooner if available, as indicated in the individual RAI responses.
This letter contains no new regulatory commitments.
COOPER NUCLEAR STATION P.O. Box 98 / Brownville, NE 68321-0098 Telephone: (402) 825-3811 / Fax: (402) 825-5211 www.nppd.com
NLS2013091 Page 2 of 2 Should you have any questions regarding this report, please contact David Van Der Kamp, Licensing Manager, at (402) 825-2904.
I declare under penalty of perjury that the foregoing is true and correct.
Executed on: O- 4--
Sincer(y, 7 Oscar . Limpias Vice President - Nuclear and Chief Nuclear Officer
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Attachment:
Cooper Nuclear Station's Response to Request for Additional Information for Reliable Spent Fuel Pool Instrumentation (Order EA- 12-051) cc: Regional Administrator, w/attachment USNRC - Region IV Director, w/attachment USNRC - Office of Nuclear Reactor Regulation Cooper Project Manager, w/attachment USNRC - NRR Project Directorate IV-1 Senior Resident Inspector, w/attachment USNRC - CNS NPG Distribution, w/attachment CNS Records, w/attachment
NLS2013091 Attachment Page 1 of 5 Attachment Cooper Nuclear Station's Response to Request for Additional Information (RAI) for Reliable Spent Fuel Pool Instrumentation (SFPI) (Order EA-12-051)
Nuclear Regulatory Commission (NRC) RAI-]: Pleaseprovide a clearly labeled sketch depicting the elevation view of the proposed typical mounting arrangementfor the portionsof instrument channel consisting ofpermanentmeasurement channel equipment (e.g., fixed level sensors and/or stilling wells, and mounting brackets). Indicate on this sketch the datum values representingLevel 1, Level 2, and Level 3 as well as the top of the fuel racks. 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.
Nebraska Public Power District (NPPD) Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NRC RAI-2: Pleaseprovide the following:
a) A clearly labeled sketch or marked-up plant drawing of the plan view of the SFP area, depicting the SFP inside dimensions, the planned locations/placementof the primary and back-up SFP level sensors, and the proposed routing of the cables that will extendfrom the sensors toward the location of the local electronics cabinets and read-out/displaydevices in the main control room or alternateaccessible location.
b) In Figure 1 of your submittal, it appears that the sensors will be separated by a distance comparableto the longest side of the pool, however your text states that they will be "separatedby a distance that is comparableto the shortest side of the pool."
Please clarify this discrepancy.
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NRC RAI-3: Pleaseprovide the following:
a) The design criteriathat will be used to estimate the total loadingon 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 resultfrom pool sloshing or other effects that could accompany such seismic forces.
NLS2013091 Attachment Page 2 of 5 b) A description of the manner in which the level sensor (and stilling well, if appropriate)will be attached to the refuelingfloor and/or other supportstructures for each plannedpoint of attachment of the probe assembly. Indicate in a schematic the portions of the level sensor that will serve as points of attachmentfor mechanical/mountingor electricalconnections.
c) A descriptionof the manner by which the mechanical connections will attach the level instrument to permanent SFP structuresso as to support the level sensor assembly.
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NRC RAI-4: Pleaseprovide the following:
a) A description of the specific method or combination of methods you intend to apply to demonstrate the reliabilityof the permanently installed equipment under Beyond-Design-Basis (BDB) ambient temperature,humidity, shock, vibration, and radiationconditions.
b) A description of the testing and/or analyses that will 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 discussion of this seismic reliabilitydemonstration as it applies to: (a) the level sensor mounted in the SFP area, and (b) any control boxes, electronics, or read-out and re-transmittingdevices that will be employed to convey the level informationfrom the level sensor to the plant operatorsor emergency responders.
c) A description of the specific method or combination of methods that will be used to confirm the reliabilityof the permanently installed equipment such thatfollowing a seismic event the instrument will maintain its requiredaccuracy.
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NRC RAI-5: Pleaseprovide the following:
a) A description of how the two channels of the proposed level measurement system in each pool meet this requirementso that the potentialfora common cause event to adversely affect both channels is minimized to the extent practicable.
b) Furtherinformation describingthe design and installationof each level measurement system, consisting of level sensor electronics, cabling, and readoutdevices. Please address how independence of these components of the primary and back-up channels
NLS2013091 Attachment Page 3 of 5 is achieved through the applicationof independent power sources,physical and spatialseparation,independence of signals sent to the location(s) of the readout devices, and the independence of the displays.
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NRC RAI-6: Pleaseprovide the following:
a) A description of the electricalAC power sources and capacitiesfor the primary and backup channels.
b) If the level measurement channels are to be powered through a battery system (either directly or through an UninterruptiblePower Supply (UPS)), please provide the design criteria that will be applied to size the batter in a manner that ensures, with margin, that the channel will be available to run reliably and continuouslyfollowing the onset of the BDB event for the minimum durationneeded, consistent with the plant mitigationstrategiesfor BDB external events (OrderEA-12-049).
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NRC RAI-7: Pleaseprovide the following:
a) An estimate of the expected instrument channel accuracyperformance (e.g., in % of span) under both: (a) normal SFP level conditions (approximatelyLevel 1 or higher) and (b) at the BDB conditions (i.e., radiation,temperaturehumidity, 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 usedfor determiningthe maximum allowed deviationfrom the instrument channel design accuracy that will be employed under normaloperatingconditions as an acceptance criterionfor a calibration procedure to flag to operatorsand to technicians that the channel requires adjustment to within the normal condition design accuracy.
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NLS2013091 Attachment Page 4 of 5 NRC RAI- 8: Pleaseprovide the following:
a) A descriptionof the capabilityand 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.
b) A descriptionof how such testing and calibrationwill enable the conduct of regular channel checks of each independent channel againstthe other, and against any other permanently-installedSFP level instrumentation.
c) A descriptionof how calibrationtests andfunctional checks will be performed and the frequency at which they will be conducted. Discuss how these surveillances will be incorporatedinto the plant surveillanceprogram.
d) A descriptionof what preventive maintenance tasks are requiredto be performed during normal operation, and the planned maximum surveillance interval that is necessary to ensure that the channels arefully conditioned to accurately and reliably perform theirfunctions when needed.
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The final design will include aspects such as procedure guidance, maintenance, and testing requirements. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NRC RAI-9: Pleaseprovide the following:
a) The specific locationfor the primary and backup instrument channel display.
b) If the primary and backup display locations are not in the main controlroom, please provide a descriptionof the display location that addressesprimary and alternate access route evaluation, continuous habitabilityat display location(s), continual resource availabilityfor personnel responsible to promptly read displays, and provisionsfor verbal communications with decision makers for the various SFP drain down scenariosand external events.
c) The reasonsjustifying why the locations selected will enable the informationfrom these instruments to be considered '"promptlyaccessible." Include considerationof various drain-down scenarios.
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NLS2013091 Attachment Page 5 of 5 NRC RAI-IO: Pleaseprovide the following:
a) A list of the operating(both normal and abnormalresponse)procedures, calibration/testprocedures,maintenanceprocedures,and inspectionprocedures that will be developedfor use of the spentfuel pool instrumentationin a manner that addresses the orderrequirements.
b) A briefdescriptionof the specific technical objectives to be achieved within each procedure. Ifyour plan incorporatesthe use ofportable spentfuel level monitoring components, please include a descriptionof the objectives to be achieved with regard to the storage location and provisionsfor installationof the portable components when needed.
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The final design will include aspects such as procedure guidance, maintenance, and testing requirements. The requested information will be provided with the August 2014, six-month status report, or sooner if available.
NRC RAI-11: Pleaseprovide the following:
a) Furtherinformation describingthe maintenanceand testing program the licensee will establish and implement to ensure that regulartesting and calibrationis performed and verified by inspection and audit to demonstrate conformance with design and system readinessrequirements. Include a descriptionof the plansfor ensuring that necessary channel checks,functional tests, periodic calibration,and maintenance will be conductedfor the level measurement system and its supportingequipment.
b) A description of how the guidance in NEI 12-02 Section 4.3 regardingcompensatory actionsfor one or both non-functioning channels will be addressed.
c) A description of the compensatory actions to be taken in the event that one of the instrument channels cannot be restoredto functional status within 90 days.
NPPD Response: NPPD has started the design phase for the SFPI Order and expects to have final design completion by July 2014. The final design will include aspects such as procedure guidance, maintenance, and testing requirements. The requested information will be provided with the August 2014, six-month status report, or sooner if available.