ML110470002

Issuance of an Amendment Regarding 3.3.2 Engineered Safety Features Actuation System Instrumentation and Section 3.3.6 Containment Ventilation Isolation Instrumentation

ML110470002
Person / Time
Site:	Robinson
Issue date:	03/07/2011
From:	Mozafari B Plant Licensing Branch II
To:	Duncan R Carolina Power & Light Co
Mozafari B, NRR/ADRO/DORL, 415-2020
References
TAC ME3507
Download: ML110470002 (14)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 March 7, 2011 Mr. Robert J. Duncan II, Vice President Carolina Power & Light Company H. B. Robinson Steam Electric Plant Unit No.2 3581 West Entrance Road Hartsville, South Carolina 29550

SUBJECT:

H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO.2 - ISSUANCE OF AMENDMENT REGARDING TECHNICAL SPECIFICATIONS SECTION 3.3.2, ENGINEERED SAFETY FEATURES ACTUATION SYSTEM INSTRUMENTATION AND SECTION 3.3.6, CONTAINMENT VENTILATION ISOLATION INSTRUMENTATION (TAC NO. ME3507)

Dear Mr. Duncan:

The Nuclear Regulatory Commission (NRC) has issued the enclosed Amendment No. 225 to Renewed Facility Operating License No. DPR-23 for the H. B. Robinson Steam Electric Plant, Unit No.2 (HBR). This amendment changes the HBR Technical Specifications (TSs) in response to your application dated March 5, 2010, as supplemented November 1, 2010.

The amendment revises HBR's TS Section 3.3.2, "Engineered Safety Feature Actuation System (ESFAS) Instrumentation." The changes would add notes to TS 3.3.2 Conditions D and E to allow a channel to be taken out of its required trip condition in order to support maintenance activities to restore channel operability. In addition, an editorial change is proposed for Table 3.3.6.1 to correct the function reference provided for the safety injection function.

A copy of the related safety evaluation is enclosed. A notice of issuance will be included in the NRC's biweekly Federal Register notice.

Sincerely, I

ilxal{/I/{, '1)&"7

'"-~ , /

JakL l

Brenda L. Mozafari, Senior Pr ec'Manager Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-261

Enclosures:

1. Amendment No. 225 to DPR-23

2. Safety Evaluation cc w/enclosures: Distribution via Listserv

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 CAROLINA POWER & LIGHT COMPANY DOCKET NO. 50-261 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO.2 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 225 Renewed License No. DPR-23

1. The Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment by Carolina Power & Light Company (the licensee), dated March 5, 2010, as supplemented November 1, 2010, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in Title 10 of the Code of Federal Regulations (10 CFR) Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.

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2. Accordingly, the license is amended by changes to the Technical Specifications, as indicated in the attachment to this license amendment; and paragraph 3.B. of Renewed Facility Operating License No. DPR-23 is hereby amended to read as follows:

B. Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 225 are hereby incorporated in the license.

The licensee shall operate the facility in accordance with the Technical Specifications.

3. This license amendment is effective as of the date of its issuance and shall be implemented within 60 days.

FOR THE NUCLEAR REGULATORY COMMISSION

~~a£-

Douglas A. Broaddus, Chief Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Attachment:

Changes to Operating License No. DPR-23 and the Technical Specifications Date of Issuance: March 7, 2011

ATTACHMENT TO LICENSE AMENDMENT NO. 225 RENEWED FACILITY OPERATING LICENSE NO. DPR-23 DOCKET NO. 50-261 Replace page 3 of Operating License No. DPR-23 with the attached page 3.

Replace the following pages of the Appendix A Technical Specifications with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.

Remove Pages Insert Pages 3.3-21 3.3-21 3.3-39 3.3-29

-3 neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required; D. Pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use in amounts as required any byproduct, source, or special nuclear material without restriction to chemical or physical form for sample analysis or instrument and equipment calibration or associated with radioactive apparatus or components; E. Pursuant to the Act and 10 CFR Parts 30 and 70, to possess, but not separate, such byproduct and special nuclear materials as may be produced by operation of the facility.

3. This renewed license shall be deemed to contain and is subject to the conditions specified in the following Commission regulations: 10 CFR Part 20, Section 30.34 of 10 CFR Part 30, Section 40.41 of 10 CFR Part 40, Section 50.54 and 50.59 of 10 CFR Part 50, and Section 70.32 of 10 CFR Part 70; and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect; and is subject to the additional conditions specified or incorporated below:

A. Maximum Power Level The licensee is authorized to operate the facility at a steady state reactor core power level not in excess of 2339 megawatts thermal.

B. Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 225 are hereby incorporated in the license.

The licensee shall operate the facility in accordance with the Technical Specifications.

(1) For Surveillance Requirements (SRs) that are new in Amendment 176 to Final Operating License DPR-23, the first performance is due at the end of the first surveillance interval that begins at implementation of Amendment 176. For SRs that existed prior to Amendment 176, including SRs with modified acceptance criteria and SRs whose frequency of performance is being extended, the first performance is due at the end of the first surveillance interval that begins on the date the Surveillance was last performed prior to implementation of Amendment 176.

Renewed Facility Operating License No. DPR-23 Amendment No. 225

ESFAS Instrumentation 3.3.2 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C. One tra'j n i noperab 1e. C.1 Restore train to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OPERABLE status.

-OR C.2.1 Be in MODE 3. 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br />

-AND C.2.2 Be in MODE 5. 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> D. One channel . ........ ---NOTE* . ---, -..... -

inoperable. For Function 4.c. a channel may be taken out of the trip condition for 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> for maintenance .

0.1 Place channel in 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> trip.

-OR 0.2.1 Be in MODE 3. 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />

-AND 0.2.2 Be in MODE 4. 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> E. One Containment ' ......... -. NOTE --. << *** - - - - - -

Pressure channel For Functions 2.c and 3.b.(3).

inoperable. a channel may be taken out of the trip condition for 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> for maintenance .

E.1 Place channel in 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> trip.

-OR E.2.1 Be in MODE 3. 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />

-AND E.2.2 Be in MODE 4. 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br />

-AND E.2.3 Be in MODE 5. 42 hours4.861111e-4 days <br />0.0117 hours <br />6.944444e-5 weeks <br />1.5981e-5 months <br /> (continued)

HBRSEP Unit No. 2 3.3-21 Amendment No. 225

Containment Ventilation Isolation Instrumentation 3.3.6 Table 3.3.6*1 (page 1 of 1)

Containment Ventilation Isolation Instrumentation FUNCTION APPLICABLE REQUIRED SURVEILLANCE TRIP MODES OR OTHER CHANNELS REQUIREMENTS SETPOINT SPECIFIED CONDITIONS

l. Manual Initiation 1.2.3.4. (a) 2 SR 3.3.6.6 NA

2. Automatic Actuation Logic and 2 trains SR 3.3.6.2 NA Actuation Relays 1.2.3.4. (a) SR 3.3.6.3 SR 3.3.6.5

3. Containment Radiation

a. Gaseous 1.2.3.4. (a) 1 SR 3.3.6.1 ( b)

SR 3.3.6.4 SR 3.3.6.7

b. Particul ate 1.2.3.4. (a) 1 SR 3.3.6.1 (b)

SR 3.3.6.4 SR 3.3.6.7

4. Safety Injection Refer to LCO 3.3.2, "ESFAS Instrumentation." Function 1. for all initiation functions and requirements.

(a) During movement of recently irradiated fuel assemblies within the containment.

(b) Trip Setpoint shall be in accordance with the methodology in the Offsite Dose Calculation Manual.

HBRSEP Unit No. 2 3.3-39 Amendment No. 225

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555*0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 225 TO RENEWED FACILITY OPERATING LICENSE NO. DPR-23 CAROLINA POWER & LIGHT COMPANY H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO.2 DOCKET NO. 50-261

1.0 INTRODUCTION

By letters dated March 5, 2010 (Agencywide Documents and Access Management System (ADAMS) Accession No. ML100710678), as supplemented November 1,2010 (ADAMS Accession No. ML103090167), Carolina Power & Light Company (CP&L, the licensee), now doing business as Progress Energy Carolinas, Inc., submitted a request to revise the Technical SpeCifications (TSs), to Facility Operating License No. DPR-23 for the H. B. Robinson Steam Electric Plant, Unit 2 (Robinson). The supplement dated November 1, 2010, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the staff's original proposed no significant hazards consideration determination as published in the Federal Register on June 1, 2010 (75 FR 30443). The changes would add notes to Technical Specification (TS) 3.3.2 Conditions D and E to allow a channel to be taken out of its required trip condition in order to support maintenance activities to restore channel operability. In addition, an editorial change is proposed for Table 3.3.6.1 to correct the function reference provided for the safety injection function.

2.0 REGULATORY EVALUATION

The regulatory requirements and guidance which the Nuclear Regulatory Commission (NRC) staff considered in its review of the applications are as follows:

1. Title 10 of the Code of Federal Regulations (10 CFR) Part 50 establishes the fundamental regulatory requirements with respect to the domestic licensing of nuclear production and utilization facilities. Specifically, Appendix A, "General Design Criteria for Nuclear Power Plants," to 10 CFR Part 50 provides, in part, the necessary design, fabrication, construction, testing, and performance requirements for structures, systems, and components important to safety.

2. General Design Criteria (GDC)-10, "Reactor design," requires that the reactor core and associated coolant, control, and protection systems be designed with appropriate margin to assure that specified acceptable fuel design limits are not exceeded during Enclosure

- 2 any condition of normal operation, including the effects of anticipated operational occurrences.

3. GDC-13, "Instrumentation and control," requires that instrumentation shall be provided to monitor variables and systems over their anticipated ranges for normal operation, for anticipated operational occurrences, and for accident conditions as appropriate to assure adequate safety, including those variables and systems that can affect the fission process, the integrity of the reactor core, the reactor coolant pressure boundary, and the containment and its associated systems. Appropriate controls shall be provided to maintain these variables and systems within prescribed operating ranges.

4. GDC-20, "Protective system functions," requires the protection system be designed (1) to initiate automatically the operation of appropriate systems including the reactivity control systems, to assure that specified acceptable fuel design limits are not exceeded as a result of anticipated operational occurrences and (2) to sense accident conditions and to initiate the operation of systems and components important to safety.

5. GDC-21, "Protection System Reliability and Testability," requires that the system be designed for high functional reliability and in service testability, with redundancy and independence sufficient to preclude loss of the protection function from a single failure and preservation of minimum redundancy despite removal from service of any component or channel.

6. GDC-22, "Protection System Independence," requires that the system be designed so that natural phenomena, operating, maintenance, testing and postulated accident conditions do not result in loss of the protection function.

7. GDC-23, "Protection System Failure Modes," requires that the system be designed to fail to a safe state in the event of conditions such as disconnection, loss of energy, or postulated adverse environments.

8. GDC-24, "Separation of Protection and Control Systems," requires that interconnection of the protection and control systems shall be limited to assure safety in case of failure or removal from service of common components.

9. 10 CFR 50.36 - "Technical specifications," states, "Each applicant for a license authorizing operation of a production or utilization facility shall include in his application proposed technical specifications in accordance with the requirements of this section." Specifically, 10 CFR 50.36(c)(2)(ii) sets forth four criteria to be used in determining whether a limiting condition for operation is required to be included in the TS.

10. 10 CFR 50.55a(h) requires that the protection systems meet the standards set by the Institute of Electrical and Electronic Engineers (IEEE) in IEEE 279. Section 4.2 of IEEE 279 -1971 discusses the general functional requirement for protection systems to assure they satisfy the single failure criterion.

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3.0 TECHNICAL EVALUATION

The license amendment request submitted by CP&L relates to the safety functions provided by the Robinson plant's containment pressure instrumentation. The containment pressure instrumentation supports the following safety functions that are performed by the plant's engineered safety features actuation system.

1. Main Steam Line Isolation, (function 4c as defined in Technical Specifications)

2. Containment Spray Initiation, and (function 2c as defined in Technical Specifications)

3. Containment Phase B Isolation Initiation (function 3b as defined by Technical Specifications)

Each of these safety functions is designed to initiate when the containment pressure exceeds a prescribed high-high setpoint. Six Containment Pressure - High High channels are included in the plant's design. These channels are divided into two groups of three as shown in Figure 1 below. The logic for actuation of the emergency safety features for the three specified safety functions is two-out-of-three on two sets of three channels.

Figure 1. Robinson ESFAS Two of Three Logic Taken twice.

(Reference Figure 7.2.1-24 of the Robinson UFSAR)

CP Sensor CP Sensor PC 951A PC 950 II PC 953A

'--..,.----..... III 1111 PC 955A PC 954 Containment Pressure Bistables are Energize to Actuate Both Actuation divisions must Energize to Actuate the Safety Function

-4 If one containment pressure channel's trip function is defeated, then the required safety functions will remain operable and will actuate when required by plant conditions as long as the other two sensor channel trip functions within the affected safety division remain operable.

For the case of the Main Steam Line Isolation function, two diverse safety system functions do exist that would ensure completion of the required Main Steam Line Isolation function even if the Containment Pressure - High High actuation did fail. The steam lines would still automatically isolate on either High Steam Flow in Two Steam Lines Coincident with Tavg - Low, or on High Steam Flow in Two Steam Lines Coincident with Steam Line Pressure - Low.

For the cases of Containment Spray Initiation, and Containment Phase B Isolation Initiation, no diverse automatic safety functions exist, however, manual actuation of these functions is available in the event that the Containment Pressure - High High actuation function fails.

The Containment Pressure - High High channels are uniquely designed in that they are required to be energized to be in the trip condition. This design feature was chosen to ensure that a loss of power would not result in an inadvertent initiation of containment spray, as the adverse consequences of initiating containment spray could be significant.

Current TS require initiation of a plant shutdown if the channel trip function is defeated after the initial 6-hour limiting condition for operation (LCO) action time has passed. When a channel trip function fails and cannot be restored to an operable status within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, the TSs allow for the channel to be placed into a tripped status to avoid the plant shutdown. Once tripped, the channel cannot be restored to a nontripped status until channel operability is restored.

3.1 Proposed Change The licensee has requested to add a note to the applicable TSs that would allow a temporary restoration of an inoperable channel to a nontripped status after the 6-hour LCO time has elapsed in order to support maintenance of the channel (for the purpose of restoring the channel operability) without requiring the extraordinary measures that would be needed to maintain the channel in a tripped state during the maintenance activity described in the licensee's submittal of March 5,2010. The length of time that would be allowed for this temporary restoration to a nontripped status is 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. This time would be separate from the existing LCO time and would be tracked on a cumulative basis such that the total amount of time that an inoperable channel could be in a nontripped condition would not exceed 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

The licensee has made an argument that the extraordinary measures that must be taken to maintain a failed channel in its tripped state pose an undue risk to plant safety because of the potential for causing a fault to a safety related alternating current power system during the maintenance activity. By allowing a temporary loss of power to the affected channel during the maintenance activity, the channel could be restored to an operable status without incurring the additional risks associated with maintaining the trip condition. The licensee also considers the proposed 6-hour additional allowance to be acceptable based on the following;

1. The low probability of an accident or transient occurring during that time period,

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2. The high probability that the Containment Pressure - High High channels will still perform their actuation function, and

3. The availability of other means to actuate the safety features.

For the case of the Main Steam Line Isolation safety function, the NRC staff agrees with the bases provided by the licensee since adequate diverse automatic means of actuating the safety features has been provided. For the Containment Spray Initiation and Containment Phase B Isolation Initiation functions, however, the only other means of actuating the safety features is through the use of manual actuation.

In the response dated November 1, 2010, to the NRC staff's request for additional information, the licensee provided an analysis of the effects of adding the 6-hour unavailability of the containment pressure signal on the large early release frequency of the probabilistic safety assessment. This analysis concluded that the proposed change will present a very small risk increase. The reliability of the unaffected channels is considered high based upon industry data.

The NRC staff has reviewed the licensee's proposed TS revision and concludes that the note proposed to be added to the technical specifications that allows an inoperable containment pressure channel to be placed in a non-tripped status to support maintenance activities is consistent with the principals of good maintenance practices. The NRC staff also agrees with the licensee's assertion that the alternative measures to maintain an inoperable channel in a tripped state during such maintenance activities would pose a higher level of risk to plant safety.

Based on this information the NRC staff finds the proposed TS change acceptable.

In addition, the licensee is proposing a change to TS 3.3.6 to revise the Note for Function 4, the initiation of Safety Injection, as listed in Table 3.3.6-1, as follows:

"Refer to LCO 3.3.2, "ESFAS Instrumentation," Function 1 for all initiation functions and requirements."

The current TS note is inaccurate as it references Functions 1. a-f, but fails to include Function 1g, which should be included. The proposed note, by referencing the Function 1 in general, indicates that each sUb-function is included. The NRC staff agrees that this change to TS 3.3.6 represents an administrative correction, as no actual changes to plant design or operation are involved.

4.0 STATE CONSULTATION

In accordance with the NRC's regulations, the State of South Carolina official was notified of the proposed issuance of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no

-6 significant increase in individual or cumulative occupational radiation exposure. The NRC has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (75 FR 30443).

Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

6.0 CONCLUSION

The NRC has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the NRC's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributor: Richard Stattel Date: March 7, 2011

March 7, 2011 Mr. Robert J. Duncan II, Vice President Carolina Power & Light Company H. B. Robinson Steam Electric Plant Unit NO.2 3581 West Entrance Road Hartsville, South Carolina 29550

SUBJECT:

H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO.2 - ISSUANCE OF AMENDMENT REGARDING TECHNICAL SPECIFICATIONS SECTION 3.3.2, ENGINEERED SAFETY FEATURES ACTUATION SYSTEM INSTRUMENTATION AND SECTION 3.3.6, CONTAINMENT VENTILATION ISOLATION INSTRUMENTATION (TAC NO. ME3507)

Dear Mr. Duncan:

The Nuclear Regulatory Commission (NRC) has issued the enclosed Amendment No. 225 to Renewed Facility Operating License No. DPR-23 for the H. B. Robinson Steam Electric Plant, Unit No.2 (HBR). This amendment changes the HBR Technical Specifications (TSs) in response to your application dated March 5, 2010, as supplemented November 1, 2010.

The amendment revises HBR's TS Section 3.3.2, "Engineered Safety Feature Actuation System (ESFAS) Instrumentation." The changes would add notes to TS 3.3.2 Conditions D and E to allow a channel to be taken out of its required trip condition in order to support maintenance activities to restore channel operability. In addition, an editorial change is proposed for Table 3.3.6.1 to correct the function reference provided for the safety injection function.

A copy of the related safety evaluation is enclosed. A notice of issuance will be included in the NRC's biweekly Federal Register notice.

Sincerely, IRA!

Brenda L. Mozafari, Senior Project Manager Plant Licensing Branch 11-2 Division of Operating Reactor licenSing Office of Nuclear Reactor Regulation Docket No. 50-261

Enclosures:

1. Amendment No. 225 to DPR-23

2. Safety Evaluation cc w/enclosures: Distribution via Listserv DISTRIBUTION:

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