ML12073A224

Instrumentation and Controls Staff Information Requests

ML12073A224
Person / Time
Site:	Watts Bar
Issue date:	03/02/2012
From:	Hruby R Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML12073A224 (15)

Text

Attachments 1 and 7 are to be withheld from public disclosure under 10 CFR § 2.390.

When separated from these attachments, this letter is decontrolled.

Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381-2000 March 2, 2012 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 2 10 CFR 50.4 NRC Docket No. 50-391

Subject:

WATTS BAR NUCLEAR PLANT (WBN) UNIT 2 - INSTRUMENTATION AND CONTROLS STAFF INFORMATION REQUESTS

Reference:

Supplemental Safety Evaluation Report (SSER) 22, 23, 24 and 25 Appendix HH Watts Bar Unit 2 Action Items Table The purpose of this letter is to provide TVA's responses to NRC information requests regarding:

• NRC to TVA letter dated November 18, 2011, "Watts Bar Nuclear Plant, Unit 2 - Request for Additional Information Regarding Supplemental Safety Evaluation Report Open Items 80, 81, 94, 105, and 108 (TAC NO. ME0853)" (ML113130218)

• NRC to TVA e-mail (J. Poole, NRC, to G. Arent, TVA), "Draft Request for Additional Information Regarding Open Item 98," sent December 12, 2011

" NRC to TVA e-mail (J. Poole, NRC, to G. Arent, TVA), "Draft Request for Additional Information Regarding Open Item 126," sent February 13, 2012 to this letter provides TVA's responses to the information requested by NRC. contains a list of attachments that support TVA's responses provided in . Enclosure 3 contains the list of references associated with TVA's commitments and responses. Enclosure 4 lists the new regulatory commitment contained in this letter. contains information proprietary to General Atomics Electronic Systems, Inc.,

(GA-ESI). TVA requests that the GA-ESI proprietary information be withheld from public disclosure in accordance with 10 CFR § 2.390. contains information proprietary to Westinghouse Electric Company LLC (WEC). contains the necessary information supporting the request for withholding such

U.S. Nuclear Regulatory Commission Page 2 March 2, 2012 information. TVA requests that the WEC proprietary information be withheld from public disclosure in accordance with 10 CFR § 2.390.

If you have any questions, please contact Gordon Arent at (423) 365-2004.

I declare under penalty of perjuryI that the foregoing is true and correct to the best of my knowledge. Executed on the 2 n day of March 2012.

Respectfully, Raymond. A. Hruby, Jr.

General Manager, Technical Services Watts Bar Unit 2

Enclosures:

1. TVA Responses to Instrumentation and Controls Staff Information Requests

2. List of Attachments

3. List of References

4. New Regulatory Commitment cc (Enclosures):

U. S. Nuclear Regulatory Commission Region II Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, Georgia 30303-1257 NRC Resident Inspector Unit 2 Watts Bar Nuclear Plant 1260 Nuclear Plant Road Spring City, Tennessee 37381

Enclosure 1 TVA Letter Dated March 2, 2012 TVA Responses to Instrumentation and Controls Staff Information Requests ACRONYMS AND ABBREVIATIONS The following acronyms/abbreviations are used in this letter:

ABB ASEA Brown Boveri BISI Bypassed and Inoperable Status Indication CIT/FAT Channel Integration Test/Factory Acceptance Test Common Q Common Qualified Platform CRC Cyclic Redundancy Check EDCR Engineering Document Change Request EDMS Enterprise Document Management System EQ Environmental Qualification FSAR Final Safety Analysis Report GA-ESI General Atomics-Electronic Systems, Inc.

ICI In-Core Instrument IITA In-Core Instrument Thimble Assembly IV&V Independent Verification and Validation MTP Maintenance and Test Panel NRC Nuclear Regulatory Commission PAMS Post Accident Monitoring System PLC Programmable Logic Controller QMS Quality Management System RAI Request for Additional Information RG Regulatory Guide SDOE Secure Development and Operating Environment SER Safety Evaluation Report SSER Supplemental Safety Evaluation Report TVA Tennessee Valley Authority V&V Verification and Validation WBN Watts Bar Nuclear Plant WEC Westinghouse Electric Company LLC NOTE

1. For some NRC requests for additional information (RAIs), this letter provides TVA's initial response. For the other NRC RAIs in this letter, a response has been provided in previous TVA letters to the NRC, and the NRC has subsequently requested additional information.

For these requests, the initial TVA response is not repeated below. The additional NRC information requests are identified in this letter as "Follow-up NRC Requests." TVA responses to these items are identified as "TVA Response to Follow-up NRC Request."

E1-1

Enclosure I TVA Letter Dated March 2, 2012 TVA Responses to Instrumentation and Controls Staff Information Requests RAI AND COMMITMENT RESPONSES

1. NRC Request (SSER 23 Appendix HH Item Number 98)

TVA should demonstrate that the WBN Unit 2 Common Q PAMS is in conformance with RG 1.152, Revision 2, or provide justification for not conforming. (Section 7.5.2.2.3)

Follow-up NRC Request The following RAIs are regardingthe Watts Bar 2 Common Q PAMS Secure Development and OperationalEnvironment. The action associatedwith this review area is captured in SSER 23 Appendix HH, Action Item 98 (ML11270A306). TVA submitted documents (reference below) on September 1, 2011 to address this item.

1) Platform Development - The US Nuclear Regulatory Commission staff notes that the Common Q platform was subject to commercial grade dedication and that a topical report on the platform was reviewed and approved by the staff (ML003740165).

However, at the time of the staff's previous review, no evaluation was performed regardingthe secure development environment for the Common Q platform and the staff is aware that the platform has undergone changes. Regulatory Guide 1.152, Revision 3, which is cited by the licensee as being used to conform to establishing a secure development environment, contains regulatorypositions related to ensuring that superfluous features are not present in software-based safety systems that could present the potential for degradingthe reliable operation of the system.

a) Since the Common Q platform was originally designed to potentially serve in several different plant applications,please provide references for and a description of any analyses that were performed to determine if there are any superfluous functions or features resident on the platform (i.e., in any of the platform software or software-driven components, such as PLCs) that are not utilized by the Common Q platform or post accident monitoring system (PA MS) application, as well as a summary of the results of such analyses. If any unnecessaryfunctions or features were identified,please explain what measures were taken to resolve any potential impact on the Common Q platform or PAMS application operation (i.e.,

were features disabled, removed or determined by analysis not to have potential to impact operations?). [e.g., the staff notes that in Attachment 9 of the September 1, 2011, Request for Additional Information responses (ML11257A050), it is stated that the Function Enable keyswitch on the OperatorsModule was not installedfor the Watts Bar Unit 2 PAMS application,and that the Operator'sModule has no connection to a printer.]

E1-2

Enclosure I TVA Letter Dated March 2, 2012 TVA Responses to Instrumentation and Controls Staff Information Requests b) It is essentialthat the Common Q platform operating system software be maintained in a fashion that protects it from unauthorizedchanges. Please confirm that WNA-LI-00058-WB T-P, Rev. 3, Sections 2.2.1 and 2.2.2 (ML110950334) describe the changes made to the platform. If not, please provide a description of changes made (including removal of unnecessary features) to the Common Q operatingsystem software since it was initially subject to commercial grade dedication and analyses were performed of the features resident on the platform.

Please describe the processes followed to ensure that only authorized changes have been made.

c) WCAP-1 7427-P, Revision 1 (ML11257A061) states that the approved version of the QNX software is protected by a CRC stamp to ensure that the correct configurationis used. Forthe WBN Unit 2 PAMS application,provide documentation indicatingyour confirmation that the CRC stamp for QNX was verified to be the correct version intended for use.

d) WCAP-1 7427-P, Revision 1 states that the ACI60 software is under strict configurationcontrols and that any changes are jointly approved by Westinghouse and ABB. Please confirm that the summary of changes provided in Section 2.2.2 of WNA-LI-00058-WB T-P, Revision 3 (ML110950334) accuratelyreflects modifications since dedication. Also, please describe what measures were taken to ensure that the correct,commercially-dedicatedversion of AC160 software is installed on the WBN Unit 2 PAMS system.

2) Application Development - Staff reviewed WCAP-1 7427-P, Revision I and found it to be largely consistent with APP-GW-JOR-012, Revision 1 (ML102170268 dated June 2010). However, much of the processes described are in future-tense and it is not clear to the staff what actions were accomplishedfor this particularWatts Bar Unit 2 PAMS application development to establish a secure development environment.

WCAP-1 7427-P, Rev 1 (MLI 1257A061 dated August 2011) describes the security assessment for the Common Q PAMS for Watts Bar Unit 2.

a. In Section 2.2.3.1. 1.a, the statement is made that the Westinghouse Quality Management System (QMS) "will be" followed to ensure documents from hardware and software development efforts are adequatelyprotected. Specifically, the section states that documents are to be stored in the Enterprise Document Management System (EDMS).

i)Please identify what documents related to the Common Q platform development (relevant to the Watts Bar 2 PAMS) are protected under the QMS / EDMS.

ii)Pleaseidentify what documents related to the Watts Bar 2 PAMS development are protected under the QMSIEDMS.

b. In Section 2.2.3.1.1.b, discussionsof controls contained in the Software Program Manual are detailed. Pleaseprovide a confirmatory statement that the Watts Bar 2 PAMS development process conformed to these controls.

E1-3

Enclosure 1 TVA Letter Dated March 2, 2012 TVA Responses to Instrumentation and Controls Staff Information Requests

c. In Section 2.2.3.2, items 2. and 3. are identical. Please clarify if one of these items is intended to state something else.

d. In Section 2.2.3.2, the statement is made that during the implementation phase, software "shallbe" code reviewed by IV&V using a defined checklist for adherence to coding standardsand applicationrequirements. Please clarify if this step was performed for the Watts Bar Unit 2 PAMS application. Please clarify if WNA-VR-00283-WBT-P, Rev.4 (ML110770540) contains this record. If not, please provide a reference for the code review results and provide a statement indicating the findings of the review.

e. In Section 2.3.1.5, the statement is made that the security requirements "shallbe" verified and validated as partof the overall system requirements. Please clarify if this step was performed for the Watts Bar Unit 2 PAMS application. Please clarify if WNA-VR-00283-WBT-P, Rev. 4 (MLI10770540) contains this record. If not, please provide a reference for the results of the V&V of the security requirements and provide a statement indicatingthe findings of the V& V.

f In Section 2.4.1, the statement is made that an assessment of the PAMS "will be" performed to verify that requirements for security controls are implemented correctly in the design. Please clarify if this step was performed for the Watts Bar Unit 2 PAMS application. Please clarify if WNA-VR-00283-WBT-P, Rev.4 (ML110770540) contains this record. If not, please provide a reference for the results of the V&V of the security requirements and provide a statement indicating the findings of the assessment.

g. In Section 2.5.1.1, the statement is made that an IV&V assessment "will be" performed of the security requirements during the implementation phase and that any anomalies will be documented. Please clarify if this step was performed for the Watts Bar Unit 2 PAMS application. Please clarify if WNA-VR-00283-WBT-P, Rev. 4 (ML110770540) contains this record. If not, please provide a reference for the results of the IV&V of the security requirements. Please provide a brief summary of any anomalies found and, if there were any, please confirm that they were resolved in accordancewith the Software ProgramManual processes.

h. In Section 2.5.3, IV&V Phase Summary Report and Software Release Records are given as outputs of the implementationphase. Please confirm if WNA-VR-00283-WBT P, Rev. 4 (MLI 10770540) is the appropriateIV&V Phase Summary Report Record. Please provide a reference for Software Release Records documents and submit on docket.

i. In Section 2.5.3, the statement is made that the code is maintained in a "locked" area of the configuration control system. Please provide further detail regarding the "locked"area of the configurationcontrol system. (e.g., is the code stored on a removable media and physically locked somewhere? Or, is the code on an isolated computer or network and protected by software controls?).

E1-4

Enclosure 1 TVA Letter Dated March 2, 2012 TVA Responses to Instrumentation and Controls Staff Information Requests

j. In Section 2.6 (and its subsections), testing activities are described in future-tense.

Pleaseprovide a brief summary of the testing results as they pertain to security requirements for the system. Do WNA-TR-02451-WB T (ML110950332) and WNA-VR-00283-WBT-NP, Rev. 4 (ML110770538) representthis evidence? If not, please provide references for the documents identified in Section 2.6.3 and submit on docket.

3. Secure OperationalEnvironment - In order to establish compliance with IEEE-603 Clauses 5.6.3 and 5.9, the staff needs to ensure that a secure operationalenvironment has been establishedfor the proposed digital safety system. Regulatory Guide 1.152, Revision 3 - which the licensee has indicated it used to conform to these requirements -

provides applicable regulatorypositions.

a. Please provide a description of the analyses performed to establish what digital systems are connected to the PAMS, what behaviors those systems are capable of either in a normal or failed operatingstate and what measures were taken in the PAMS design or Watts Bar operationsto ensure its reliable operation in the presence of those potentially adverse behaviors.

b. Please provide a description of the analyses performed to establish what points of physical and logical access are present to allow interaction with the PAMS and what measures were taken in the PAMS design or Watts Bar operationsto provide assurance that only authorized personnel can access the system.

c. The "Watts Bar Nuclear Unit 2 Common Q PostAccident Monitoring System Conformance to the Secure Development and OperationalEnvironment Requirements of Regulatory Guide 1.152 Revision 3" document (ML11257A050 dated September 1, 2011) describes the licensee's activities relative to SDOE.

i) In Section 1.e (on page 7), it is noted that the testing of the Maintenance and Test Panel (MTP) software data diode function was included in the CIT/FA T and that the software data diode is the "qualified"isolation device. Pleaseprovide a summary of testing performed for this software data diode (i.e., did the testing consist of just the "datastorm" testing or were there other tests?). Also, please elaborateon what is intended by the term "qualified"(i.e., Does it indicate that it has been formally tested? Or is there some otherpedigree implied by the term?)

ii) In Section 2.a.i.(1) (on page 8), the statement is made that the touch screen on the OperatorsModules could change constants or alarm setpoints if the Function Enable keyswitch was placed in the 'enable'position. In Section 1.b of the same document, it is noted that the Function Enable keyswitch was not installed on the OperatorsModule for the PAMS. Please confirm that the OperatorsPaneldoes not possess a Function Enable keyswitch. [Note: Sections 2. a.i. (2) and 2.a.vi. (1) also mention the Function Enable keyswitch in regard to the OperatorsModule.]

E1-5

Enclosure 1 TVA Letter Dated March 2, 2012 TVA Responses to Instrumentation and Controls Staff Information Requests iii) In Section 2.a.v (on page 9), use of a hardware data diode is noted. Please clarify if this is the device referenced in the response to RAI 14b submitted on July 30, 2010 (ML102160349). If not, please provide information on the specific hardware used (i.e., vendor and model number).

TVA Partial Response to Follow-up NRC Request Note: The response to "Draft Request for Additional Information Regarding Open Item 98,"

sent December 12, 2011, Item 3, was provided in TVA to NRC letter dated December 22, 2011 (Reference 1). With the exception of item 2.h, items 1 and 2 are addressed below.

The responses to items 1 and 2 are provided in WEC proprietary document WBT-D-3769 P-Enclosure, "Watts Bar 2 Common Q PAMS Secure Development and Operational Environment SSER 23 Appendix HH Action Item 98 Requests for Additional Information."

Attachment 1 contains WEC proprietary document WBT-D-3769 P-Enclosure, "Watts Bar 2 Common Q PAMS Secure Development and Operational Environment SSER 23 Appendix HH Action Item 98 Requests for Additional Information," dated February 2012.

Attachment 2 contains WEC non-proprietary document WBT-D-3769 NP-Enclosure, "Watts Bar 2 Common Q PAMS Secure Development and Operational Environment SSER 23 Appendix HH Action Item 98 Requests for Additional Information," dated February 2012.

Attachment 3 contains WEC non-proprietary document CAW-12-3385, "Application for Withholding Information From Public Disclosure WBT-D-3769 P-Enclosure, "Watts Bar 2 Common Q PAMS Secure Development and Operational Environment SSER 23 Appendix HH Action Item 98 Requests for Additional Information, (Proprietary)," dated February 6, 2012.

Item 2.h will be addressed by submittal of WNA-VR-00283-WBT-P, Revision 7, "IV&V Summary Report," which will be submitted within three weeks of receipt from WEC.

2. NRC Request (SSER 24 Appendix HH Item Number 126)

To enable the NRC staff to evaluate and review the IITA environmental qualification, TVA should provide the summary report of the environmental qualificationfor the IITA. (SSER 24, Section 7.7.1.9.5)

Follow-up NRC Request Action Item No. 126 identified in Nuclear Regulatory Commission (NRC) NUREG-0847 "Safety Evaluation Report Related to the Operationof Watts Bar Nuclear Plant, Unit 2,"

Supplement 24 (ADAMS Accession No. ML1277A148), Section 7.7.1.9, "In-Core InstrumentationSystem," requires Tennessee Valley Authority (TVA) to "provide the summary report of the environmental qualificationfor the IITA. "

E1-6

Enclosure I TVA Letter Dated March 2, 2012 TVA Responses to Instrumentation and Controls Staff Information Requests In TVA's November 30, 2011 submittal (ADAMS Accession No. ML113410393), TVA provided a response for this item. To complete our review on this item, the NRC requires TVA to clarify the scope of Westinghouse WBT-D-3566 qualificationsummary report, which was included as Attachment 9. Specifically, the report states that "ft]heClass 1E Qualification Program applies to only the ex-vessel portion of the ICI [in-Core Instrument]

assembly." However, the qualificationhardware and results provided in the report explain that the thermocouples were part of the qualificationtesting, which indicate that the in-vessel portion of the ICI assembly was tested. Please clarify the scope and results of the qualification testing performed on the ICI assembly.

TVA Response to Follow-up NRC Request Environmental Testing:

The following response was provided in WBT-D-3806 NP-Enclosure, dated February 2012, "Open Item No.126 and Request for Supplemental Information Watts Bar Unit 2," to WEC letter WBT-D-3806, dated February 29, 2012, "Response to NRC RAI on Open Item 126 (WINCISE)," (Reference 2).

The ex-vessel portion of the Incore Instrument Thimble Assembly (IITA) (i.e., from the Swagelok fitting to the electrical connector) was subjected to the conditions of the EQ test. This ex-vessel portion is representative of the IITA that will be installed at WBN Unit 2. All components of the in-vessel portion of the qualification assembly were not completely identical to the WBN Unit 2 IITA as shown below:

a. Due to limitations of the test bed, the in-vessel portion of the qualification assembly was not the full length of the production IITA.

b. Since the self-powered neutron detectors are not required to be qualified, they were simulated using copper wires.

The thermocouple used in the in-vessel portion of the qualification assembly was a Type K thermocouple, which is the same as in the production IITAs.

During the EQ testing, the sensing end of the thermocouple (located in the in-vessel portion of the qualification assembly) was heated to a known temperature. The ex-vessel portion of the IITA was subjected to the conditions described in WBT-D-3566 and CE-NPSD-240-P, and the thermocouple response was observed.

Seismic Testing Both the ex-vessel and in-vessel portions of the qualification assembly were located on the seismic table during the seismic testing described in WBT-D-3566 and CE-NPSD-240-P.

E1-7

Enclosure I TVA Letter Dated March 2, 2012 TVA Responses to Instrumentation and Controls Staff Information Requests

3. TVA Commitment As part of the review of FSAR Section 7.6.6, the NRC reviewer requested TVA to provide objective evidence that for FCV-62-98 and FCV-62-99 the motive power has been removed in accordancewith Final Safety Analysis Report (FSAR) Section 7.6.6 "Spurious Actuation Protection for Motor Operated Valves."

Commitment Closure The motive power for FCV-62-98 was removed under Engineering Document Change Request (EDCR) 53287. The motive power for FCV-62-99 was removed under EDCR 53292. Attachment 4 contains excerpts of TVA document EDCR 53287, dated February 1, 2012. Attachment 5 contains excerpts of TVA document EDCR 53292 dated October 10, 2011.

4. TVA Commitment In TVA to NRC letter dated October5, 2010 (Reference 3), TVA committed to submit the Bypassed and Inoperable Status Indication (BISI) calculation updated for WBN Unit 2.

Commitment Closure Attachment 6 contains TVA calculation WBPEVAR8807025, Revision 8, "Bypassed and Inoperable Status Indication Logic Input Indications," which has been updated to reflect WBN Unit 2.

5. NRC Request During a telecom with the NRC on January 11, 2012, the NRC reviewerprovided the following comment:

On page 4 of the power supply documentationpackage 04502050-001, Section 3, the "BasicComponent"box is checked "NO." The NRC reviewer believes that because this component is qualified by GA-ESI that it should be checked "YES." If the correct box is NO, then please providejustification for this position. Otherwise, please resubmit this page with the box changed to YES.

TVA Response to NRC Request GA-ESI agreed that the "Basic Component" box should be checked "YES." Attachment 7 contains proprietary GA-ESI replacement pages for power supply documentation package 04502050-001. Attachment 8 contains non-proprietary replacement pages for power supply documentation package 04502050-001. The NRC is requested to replace Pages 3 through 7 of the proprietary and non-proprietary versions of power supply documentation package 04502050-001 submitted in TVA to NRC letter dated January 19, 2012 (Reference 4) with Attachments 7 and 8 respectively. The GA-ESI affidavit for withholding submitted as Attachment 10 in TVA to NRC letter dated January 19, 2012 (Reference 4) is applicable to the revised pages.

E1-8

Enclosure I TVA Letter Dated March 2, 2012 TVA Responses to Instrumentation and Controls Staff Information Requests

6. NRC Request TVA Calculation WCGACQ0766 was submitted in TVA to NRC letter dated January19, 2012 (Reference 4) as Attachment 11. The NRC identified that multiple instances of proprietaryinformation statements existed in the calculation and that the calculation could not be accepted.

TVA Response to NRC Request TVA performed a review of Calculation WCGACQ0766 to determine which proprietary notations in the calculation were appropriate. The review found that the GA-ESI proprietary notation on Page 67, GA-ESI drawing 04034100, Revision C, "Outline High Range Area Monitor System," was the only appropriate notation. This drawing is included as a source reference for sheet 8 of the calculation for dimensional and weight information. TVA reviewed the GA-ESI drawing and certifies that the information shown on sheet 8 is correct.

Attachment 9 contains redacted TVA calculation WCGACQ0766, Revision 1, "Required Response Spectra for Evaluation of Radiation Monitoring Equipment." This replaces the calculation previously submitted as Attachment 11 in the TVA to NRC letter dated January 19, 2012 (Reference 4).

El-9

Enclosure 2 TVA Letter Dated March 2, 2012 List of Attachments Note: While project coversheets have not been included, the attachments have been reviewed and approved by Engineering prior to submittal.

1. WEC proprietary document WBT-D-3769 P-Enclosure, "Watts Bar 2 Common Q PAMS Secure Development and Operational Environment SSER 23 Appendix HH Action Item 98 Requests for Additional Information," dated February 2012 (Letter Item 1, SSER 23 Appendix HH Item Number 98)

2. WEC non-proprietary document WBT-D-3769 NP-Enclosure, "Watts Bar 2 Common Q PAMS Secure Development and Operational Environment SSER 23 Appendix HH Action Item 98 Requests for Additional Information," dated February 2012 (Letter Item 1, SSER 23 Appendix HH Item Number 98)

3. WEC non-proprietary document CAW-12-3385, "Application for Withholding Information From Public Disclosure WBT-D-3769 P-Enclosure, "Watts Bar 2 Common Q PAMS Secure Development and Operational Environment SSER 23 Appendix HH Action Item 98 Requests for Additional Information, (Proprietary)," dated February 6, 2012 (Letter Item 1, SSER 23 Appendix HH Item Number 98)

4. Excerpts of TVA document EDCR 53287, dated February 1, 2012 (Letter Item 3)

5. Excerpts of TVA document EDCR 53292, dated October 10, 2011 (Letter Item 3)

6. TVA calculation WBPEVAR8807025 Revision 8, "Bypassed and Inoperable Status Indication Logic Input Indications" (Letter Item 4)

7. Demarcated Proprietary GA-ESI replacement pages for power supply documentation package 04502050-001 (Letter Item 5)

8. Redacted Non-Proprietary GA-ESI replacement pages for power supply documentation package 04502050-001 (Letter Item 5)

9. Redacted TVA calculation WCGACQ0766, Revision 1, "Required Response Spectra for Evaluation of Radiation Monitoring Equipment" (Letter Item 6)

E2-1

Enclosure 3 TVA Letter Dated March 2, 2012 List of References

1. TVA to NRC letter dated December 22, 2011, "Watts Bar Nuclear Plant (WBN) Unit 2 -

Instrumentation and Controls Staff Information Requests" (Letter Item 1, SSER 23 Appendix HH Item Number 98)

2. WEC to TVA letter WBT-D-3806, dated February 29, 2012, "Response to NRC RAI on Open Item 126 (WINCISE)" (Letter Item 2, SSER 24 Appendix HH Item Number 126)

3. TVA to NRC letter dated October 5, 2010, "Watts Bar Nuclear Plant (WBN) Unit 2 -

Instrumentation and Controls Staff Information Requests" (Letter Item 4)

4. TVA to NRC letter dated January 19, 2012, "Watts Bar Nuclear Plant (WBN) Unit 2 -

Instrumentation and Controls Staff Information Requests" (Letter Items 5 and 6)

E3-1

Enclosure 4 TVA Letter Dated March 2, 2012 New Regulatory Commitment

1. Item 2.h will be addressed by submittal of WNA-VR-00283-WBT-P, Revision7, "IV&V Summary Report," which will be submitted within three weeks of receipt from WEC.

(Letter Item 1)

E4-1

Attachment 2, WEC non-proprietary document WBT-D-3769 NP-Enclosure, "Watts-Bar 2 Common Q PAMS Secure Development and Operational Environment SSER 23 Appendix HH Action Item 98 Requests for Additional Information," dated February 2012 (Letter Item 1, SSER 23 Appendix HH Item Number 98)