ML112660001

Relief Request ADS-VR-01 for Fourth 10-year Inservice Testing Interval

ML112660001
Person / Time
Site:	Nine Mile Point
Issue date:	09/28/2011
From:	Nancy Salgado Plant Licensing Branch 1
To:	Lynch T Nine Mile Point
Guzman R, NRR/DORL 415-1030
References
TAC ME4848
Download: ML112660001 (11)

Text

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• • • • 1C Mr. Thomas A. Lynch Vice President Nine Mile Point Nine Mile Point Nuclear Station, LLC P.O. Box 63 Lycoming, NY 13093 SUB..IECT: NINE MILE POINT NUCLEAR STATION, UNIT NO.1 - REQUEST FOR ALTERNATIVE: AUTOMATIC DEPRESSURIZATION SYSTEM (ADS)-VR-01 FOR THE TESTING OF MAIN STEAM ELECTROMATIC RELIEF VALVES ASSOCIATED WITH THE FOURTH 10-YEAR INSERVICE TESTING INTERVAL (TAC NO. ME4848)

Dear Mr. Lynch:

By letter dated September 29, 2010, Agencywide Documents Access and Management System (ADAMS) Accession No. ML102800415), Nine Mile Point Nuclear Station, LLC (NMPNS, the licensee), submitted a relief request to the Nuclear Regulatory Commission (NRC), requesting to use an alternative to certain American Society of Mechanical Engineers, Code for Operation and Maintenance of Nuclear Power Plants (ASME OM Code), inservice testing (1ST) requirements pertaining to testing of the main steam Electromatic Relief Valves (ERVs). The licensee's request seeks relief from performing certain stroke testing of the main steam ERVs, PSV-01-102A thru 102F. Specifically, pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Section 55a(a)(3)(i), the licensee requested to use the proposed alternative, ADS-VR-01, on the basis that the alternative provides an acceptable level of quality and safety.

The NRC staff has reviewed the subject request, and concludes that the proposed alternative provides an acceptable level of quality and safety. Therefore, the NRC staff authorizes the proposed alternative in accordance with 10 CFR 50.55a(a)(3)(i) for the licensee's fourth 10 year 1ST interval. The results of the NRC staff's review are provided in the enclosed safety evaluation.

If you have any questions regarding this approval, please contact Richard Guzman, at 301-415-1030 or Richard.Guzman@nrc.gov.

Sincerely, 4~z/~

Nancy L. Salgado, Chief Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-220

Enclosure:

As stated cc w/encl: Distribution via Listserv

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555*0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION ALTERNATIVE REQUEST: AUTOMATIC DEPRESSURIZATION SYSTEM (ADS)-VR-01 FOR THE PUMP AND VALVE INSERVICE TESTING PROGRAM PLAN NINE MILE POINT NUCLEAR STATION, LLC NINE MILE POINT NUCLEAR STATION, UNIT NO.1 DOCKET NO. 50-220

1.0 INTRODUCTION

By letter dated September 29,2010, Agencywide Documents Access and Management System (ADAMS) Accession No. ML102800415), Nine Mile Point Nuclear Station, LLC (f'lIMPNS, the licensee), submitted a relief request to the Nuclear Regulatory Commission (NRC), requesting to use an alternative to certain American Society of Mechanical Engineers, Code for Operation and Maintenance of Nuclear Power Plants (ASME OM Code), inservice testing (1ST) requirements pertaining to testing of the main steam Electromatic Relief Valves (ERVs). The licensee's request seeks relief from performing certain stroke testing of the main steam ERVs, PSV-01-102A thru 102F. Specifically, pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Section 55a{a){3)(i), the licensee requested to use the proposed alternative, RR-ADS-VR-01, on the basis that the alternative provides an acceptable level of quality and safety. The licensee requested implementation of this alternative during the fourth 10-year 1ST interval for NMP1 which commenced on January 1, 2009, and is scheduled to end on December 31,2018.

2.0 REGULATORY EVALUATION

10 CFR 50.55a{f), "Inservice testing reqUirements," requires, in part, that ASME Class 1,2, and 3 components must meet the requirements of the ASME OM Code and applicable addenda, except where alternatives have been authorized pursuant to paragraphs (a)(3)(i) or (a)(3){ii).

In proposing alternatives, a licensee must demonstrate that the proposed alternative provides an acceptable level of quality and safety (1 0 CFR 50.55a(a)(3)(i)); or compliance would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety (10 CFR 50.55a{a)(3){ii)). Section 50.55a allows the NRC to authorize alternatives to ASME OM Code requirements upon making necessary findings. The NRC's findings with respect to authorizing RR-ADS-VR-01 are given below:

Enclosure

- 2

3.0 TECHNICAL EVALUATION

3.1 Licensee's Alternative Request RR-ADS-VR-01 The NMP1 fourth 10-year 1ST program Interval commenced on January 1, 2009, and ends on December 31, 2018. The relief request proposes an alternative to performing in-situ ERV steam pressure testing every refueling outage. The proposed alternative consists of a combination of offsite steam testing of the main valves, actuator cycling, and other inspections and maintenance activities. The basis of the request is that the proposed alternative would provide an acceptable level of quality and safety. The applicable ASME OM Code is 2004 Edition, and the licensee requested relief from the following Code requirements:

• ISTC-3510, "Exercising Test Frequency," requires that power-operated relief valves shall be exercise tested once per fuel cycle.

• ISTC-3700, "Position Verification Testing," requires that valves with remote position indicators shall be observed at least once every 2 years to verify that valve operation is accurately indicated.

• ISTC-5111, "Valve Testing Requirements," requires that position indication testing be performed.

• ISTC-5113, "Valve Stroke Testing," requires that active valves shall have their stroke times measured, and stroke testing shall be performed during normal operating conditions.

• ISTC-5114, "Stroke Test Acceptance Criteria," requires that test results shall be compared to established reference values.

Reason for Request

The licensee states that proposed alternative will allow testing of the ERVs that is appropriate to demonstrate functionality without cycling the valves in place using reactor steam pressure. The request is consistent with NUREG-0737, "Clarification of TMI Action Item Requirements," Item 11.K.3.16, "Reduction of Challenges and Failures of Relief Valves," which recommended that the number of relief valve openings be reduced as much as possible and that unnecessary challenges should be avoided.

System Description (as stated by NMPNS)

There are six Dresser Model 1525VX solenoid-actuated, pilot-operated ERVs installed at NMP1.

The ERVs are connected to the main steam lines between the main steam line flow restrictor and the inboard main steam isolation valve. Each ERV has its own discharge pipe that is equipped with an acoustic monitor to detect flow noise and a thermocouple to sense discharge fluid temperature to monitor for valve actuation and/or leakage.

- 3 The ERVs have two functional modes of operation: the ADS mode and the overpressurization relief mode. In the ADS mode, the ERVs depressurize the reactor vessel in the event of a small break loss-of-coolant accident (SBLOCA) by relieving steam to the torus, allowing the core spray system to inject (spray) cooling water into the reactor vessel. The ADS mode actuates on concurrent "10-10-10" reactor water level and high drywell pressure signals. The six ERVs, three primary valves and three backup valves, are required to be operable for the ADS mode.

Operation of three ERVs is sufficient to depressurize the reactor coolant system and permit full core spray system flow. The ERVs also provide overpressure protection (relief mode) for the reactor and main steam piping by limiting reactor pressure during transients that result in a pressure increase. In the overpressurization relief mode, pressure switches that monitor reactor vessel pressure actuate six ERVs at staggered setpoints to ensure sufficient margin between the analyzed peak transient pressure and the lowest setpoint for the reactor head safety valves to prevent safety valve actuation during anticipated transients.

Valve Operation Steam under pressure from the reactor enters the main valve and passes upward around the disc guide. Steam enters the chamber below the main disc through a small orifice located in the disc retainer plate. Inlet steam pressure holds the main valve disc closed. A main disc spring is provided to keep the main valve disc in the closed position at low pressures or while depressurized. The pilot valve disc is held in the closed position by a pilot valve spring and steam pressure in the chamber below the pilot disc. When the solenoid actuator is energized, the actuator plunger depresses the pilot valve operating lever, thereby opening the pilot valve.

When the pilot valve is opened, steam is released through the outlet port at a faster rate than supplied through the inlet orifice. This causes the chamber below the main disc to depressurize, causing the valve to open. To close the valve, the solenoid actuator is de energized, thereby closing the pilot valve and allowing steam pressure to reseat the main valve.

Each ERV consists of a main valve, a pilot valve assembly, and a solenoid actuator. The ERVs are opened by either signals from automatic actuation instrumentation or manually and, thus, do not rely on spring setpoints for valve actuation. Currently, the ASME OM Code 2004 Edition required testing for the six ERVs is satisfied by manually stroking open each ERV with the reactor at pressure once every operating cycle, which is performed during plant startup following a refueling outage. Experience in the industry and at NMP 1 indicates that manually opening the ERVs during plant operation can increase the potential for main disc seat leakage and pilot valve seat leakage. NMP1 experienced main disc seat leakage in March 2001 and pilot valve seat leakage in December 2002, both of which were attributed to debris on the seats caused by testing the valves using steam. Leakage from the main valve disc can cause increases in suppression pool (torus) temperature and level, requiring more frequent suppression pool cooling and pump-down operations, and diverts steam from the power generation steam cycle.

Excessive leakage from the pilot valve can cause inadvertent opening of the main valve and impair its ability to re-close.

The proposed alternative will allow testing of the ERVs that is appropriate to demonstrate functionality without cycling the valves in place using reactor steam pressure. This is consistent with NUREG-0737, "Clarification of TMI Action Item Requirements," Item II.K.3.16, "Reduction of Challenges and Failures of Relief Valves," which recommended that the number of relief

-4 valve openings be reduced as much as possible and that unnecessary challenges should be avoided.

3.1.1 Exercise Test Frequency Alternative to ISTC-3510 As stated by the licensee, the six ERVs are currently exercised once each operating cycle with steam during plant startup. For the proposed alternative, all six of the ERV solenoid actuators will be exercised each refueling oUfage, and three of the six main valves will be replaced with pretested spare valves each refueling outage. Inspections and precision preventive maintenance (described below) will be performed each refueling outage for all six of the solenoid actuators and pilot valve assemblies, with the 1ST requirements incorporated as part of the preventive maintenance activities. This combination of testing, inspections, and maintenance activities provides an acceptable level of quality and safety without requiring the six ERVs to be stroked with reactor steam during plant startup.

Solenoid Actuator Each ERV solenoid actuator will be exercised each refueling outage. The closing stroke de energizes the solenoid and allows the actuator to return to its fail-safe (closed) position. This test will be performed with the pilot valve and solenoid actuator mounted in their normal installed positions inside the drywell, which allows the solenoid actuator to be actuated electrically from the control room by placing the control switch in the open position. The pilot valve operating lever and pilot valve stem will be secured in the open position during this test to prevent damage to the pilot valve assembly which could result from dry-stroking with no backpressure. The maintenance activities include detailed inspections of the electrical and mechanical components of the solenoid actuator.

NMP1 Licensee Event Report (LER)03-001 reported an event involving an ERV that failed to open due to high resistance in the solenoid actuator cutout switch contacts. The high resistance contacts limited the current through the solenoid operating coil, which reduced the force that the plunger applied to the pilot valve operating lever. Further investigation and examination showed that the high contact resistance was due to the tin coating having been worn off the cutout switch contacts, allowing excessive contact oxidation to occur.

Preventive maintenance activities now include inspection and cleaning of the cutout switch contacts, as necessary. to assure that the contact surfaces are clean and free of oxidation.

corrosion, and discoloration. The contact tin plating will be verified to be intact and not worn off exposing the copper base material. Associated springs and mechanisms will be inspected, and the as-left contact resistances will be verified. Resistance checks will be performed on both actuator coils, and actuator operating currents during electrical actuation will be verified to be within acceptance limits. These steps provide substantial indication that the solenoid actuator is capable of functioning as designed and producing its full output force. Stroke timing of the solenoid actuator will not be performed since the actuator is a SUb-component of the total ERV.

Degradation is monitored through the preventive maintenance inspections in lieu of trending millisecond stroke time variations.

- 5 Pilot Valve Each ERV pilot valve will be exercised each refueling outage when the new/refurbished pilot valve assembly is installed in the pilot housing. The pilot valve housing is permanently welded to the outside of the ERV enclosure located in the drywell. Removal and reinstallation of the pilot valve assembly does not affect the ERV main valve. The maintenance activities will include inspections of the pilot valve assembly parts and the pilot valve housing interior to identify any damage or wear that could impair free movement of the stem or proper valve seating. Parts will be refurbished or replaced as necessary. Cleanliness of parts and components and absence of foreign material will be verified prior to reassembly. NMP1 has experienced a stuck-open ERV event caused by improper maintenance. This condition allowed steam to bypass the pilot valve seat, thereby preventing steam pressure from building up under the main valve disc to close the valve when given the closure signal. Appropriate precautions and instructions have been incorporated into the ERV maintenance procedure to ensure that the correct gasket is used and sufficient torque is applied to prevent steam from bypassing the pilot valve seat.

Prior to re-installing the pilot valve assembly inside the pilot housing, pilot stem/disc leak testing and freedom of movement and reseat functionality will be demonstrated. A complete cleanliness inspection will be performed prior to installing the pilot valve assembly back into the housing. The housing is thoroughly cleaned and vacuumed to remove moisture and debris to minimize the potential for debris blocking or hindering pilot valve performance. Following installation of the pilot valve assembly inside the housing, the pilot valve operating lever and pilot valve assembly freedom of movement and clearance adjustments will be confirmed, followed by stroking of the solenoid actuator plunger by hand to the full extent of travel. This will ensure that the solenoid actuator plunger, pilot valve operating lever, and pilot valve assembly function as a unit, while eliminating the risk of damage resulting from electrically stroking the pilot valve in the absence of steam pressure (referred to as dry-stroking). The pilot valve freedom of movement check allows the pilot valve disc to return to its fail-safe (closed) position.

NMP1 experienced an event involving an ERV that unexpectedly opened and would not reclose.

The cause was attributed to a bent stem in the pilot valve assembly and partial disengagement of the pilot valve disc from the stem. It was determined that the pilot valve stem-disc separation had occurred as a result of dry-stroking the ERV pilot valve using the solenoid actuator. Stroke timing of the pilot valve is not practical since the test is performed by hand and the pilot valve is a SUb-component of the total ERV. Degradation of the pilot valve assemblies will be monitored through the preventive maintenance inspections.

Main Valve A sampling program is proposed that will remove and replace three of the six ERV main valves with pre-tested spare main valves during each refueling outage, such that all six ERV main valves will be replaced every two refueling outages (approximately 4 years). Each ERV main valve will be stroke tested at an offsite steam test facility once every 4 years (two refueling outages) rather than once every refueling outage (approximately 24 months). A 6-month grace period would be allowed to accommodate variations in fuel cycle length and extended shutdown periods. The main valve testing will capture the exercise and stroke time test data required by the ASME OM Code 2004 Edition.

-6 The main valve is housed in a heavy, steel enclosure that is attached to the main steam line inlet flange. The pilot valve assembly is installed inside the pilot valve housing, and the housing is welded onto the outside of the enclosure and physically separated from the ERV main valve body. Thus, only the main valve of the ERV can be sent to the test facility. A spare pilot valve assembly and a spare solenoid actuator, both representative of the components used at the plant, will be installed at the test facility to allow testing of the main valve. The valve will be installed on a test steam header in the same orientation as the plant installation. The test conditions at the test facility will be similar to those in the plant, including ambient temperature and steam conditions. The main valve will receive an initial seat leak test, a functional test to ensure it is capable of opening and closing, and a final seat leak test. Valve stroke time will be obtained during the exercise test. Valve seat tightness will be verified by a cold bar test, and if not free of fog, leakage will be measured and verified to be below specified acceptance criteria.

This initial testing will be completed prior to plant startup from the refueling outage.

After initial testing, the main valves will be completely disassembled, inspected and refurbished, and then retested. The refurbished main valves will be stored at the offsite test facility and returned to the plant prior to the next scheduled use. The offsite test facility's storage requirements will ensure the valves are protected from physical damage. The valves will be stored in an area meeting ANSI/ASME N45.2.2 Class B storage requirements, with the storage area temperature maintained between 50 OF and 90 OF. Maintaining the ERVs in a controlled environment during storage minimizes the potential for any valve degradation.

Prior to installation at the plant, the spare main valves will be inspected for foreign material and damage. The steam line and ERV discharge line openings will also be inspected to verify cleanliness and absence of foreign material. Procedural requirements will ensure that the proper ERV inlet flange gasket separating ring thickness is provided so proper crush of the flexitallic gasket is achieved when the valve is installed. The valves will then be installed and necessary connections completed, including connecting the vent tube and installing the enclosure cover and bellows assembly. Proper connections will be verified per procedure.

The three main valve discs that are not exercised during each refueling outage will have inspections and maintenance performed on their solenoid actuators and pilot valve assemblies as described above. The licensee will also monitor the ERV discharge line temperatures during plant operation since this provides an indication of degradation of the installed main valves.

Review of past surveillance testing and preventive maintenance history indicates that the ERV main valves are highly reliable. During the second 10-year 1ST interval (1986 to 1999), the ERVs were inspected and refurbished at 48-month intervals (every two refueling outages).

From 1999 to 2004, the preventive maintenance interval for the ERV main valves was extended to 6 years, and since 2004, the preventive maintenance interval for the ERV main valves has been 10 years. These preventive maintenance activities have found the ERV main valves in excellent condition with no significant degradation noted.

While the preventive maintenance interval is extended to 10 years, the Technical Specifications (TS) requires manual opening of each ERV each operating cycle. Therefore, no TS surveillance test data exists to show how a main valve will perform if not stroked for a period beyond approximately 24 months. The only failure of an ERV to open during the last 10 years is the event reported in NMP1 LER 03-001, Technical Specification Cooldown Rate Exceeded During

-7 Required Cooldown for a Failed Solenoid Actuated Pressure Relief Valve," which was caused by a problem with the solenoid actuator, not with the main valve.

Although the NMP1 ERVs will be tested in accordance with the ASME OM Code-2004, Subsection ISTC, the proposed sampling program whereby three of the six ERV main valves will be removed and replaced with pre-tested spare main valves during each refueling outage is similar to the testing methodology for Class 1 pressure relief devices described in the ASME OM Code-2004, Mandatory Appendix I. Specifically, this Appendix specifies that Class 1 pressure relief valves shall be tested at least once every 5 years, that a minimum of 20% of the valves from each valve group shall be tested within any 24-month interval, and that the testing requirements may be satisfied by installing pretested valves to replace valves that have been in service. Extensions of the 5-year test interval have previously been authorized by the NRC.

For Nine Mile Point Unit 2 (NMP2), the NRC authorized the alternative described in Relief Request MSS-VR-01 to extend the test interval for the Class 1 main steam safety relief valves to 3 refueling cycles (approximately 6 years), as documented in an NRC letter dated December 29,2008 (ADAMS Accession No. ML083500039).

3.1.2 Position Indication Verification Alternative to ISTC-3700 and ISTC-5111 As stated by the licensee, this proposed alternative performs position indication verification for the six ERVs by observing the control room position indicating lights during the solenoid actuator test. Each ERV is equipped with red and green indicating lights which provide control room open and close indication, respectively, by monitoring the solenoid actuator plunger position. A blue indicating light is also provided in the control room which monitors power to the solenoid actuator. The blue light is "On" when the solenoid is de-energized (valve closed) and "Off when the solenoid is energized (valve open). As previously noted, the pilot valve operating lever and pilot valve stem will be secured in the open position during this test to prevent damage to the pilot valve assembly which could result from dry-stroking with no backpressure. Solenoid actuator plunger movement will also be observed locally in the drywell and compared to the control room indication to verify that solenoid actuator operation is accurately indicated. The proposed position indication verification alternative provides indirect pilot valve position, which ultimately represents the position of the main valve disc when steam is present, without cycling the ERVs in place with reactor steam pressure. This test will be performed every refueling outage for each of the six ERVs. The proposed position indication verification alternative provides an acceptable level of quality and safety without requiring indication of main valve obturator movement.

3.1.3 Stroke Time Testing Alternative to ISTC-5113 and ISTC-5114 As stated by the licensee, since the ERVs are not being in-situ tested, and since only the main valve is being tested at the offsite test facility (as previously noted), ERV full stroke time from initiating signal to indication of the end of the operating stroke cannot be obtained. Instead, main valve stroke times will be measured at the test facility. Stroke time acceptance criteria will use a pre-established reference value that represents good performance for this valve type.

Since the whole valve assembly is not being tested and the test facility cannot duplicate the control circuitry, a simplified valve actuation circuit will be used. Although these differences may result in minor differences in measured stroke time compared to previous test data for in-situ

- 8 testing of the complete ERV, the stroke times measured at the test facility will be comparable to each other and, thus, can be used to detect abnormalities in valve performance.

3.2 NRC Staff Evaluation The NRC staff has reviewed the licensee's request for relief and finds that with the proposed alternative testing of the ERVs, the functional capability of the valves is adequately verified. A manual actuation and valve leakage test will be performed at a steam test facility using test conditions similar to those for the installed valves in the plant, including valve orientation, ambient temperature, and steam conditions. Following ERV installation, the licensee's proposed testing includes verifying proper electrical connections and actuator performance.

Although the tests of the ERVs at the steam test facility are not performed with the actual valve solenoids installed in the plant, the solenoids are adequately tested and verified by separate tests. The NRC staff also finds that the licensee's reduction of the test frequency of the ERV main valve disks from every cycle to every two cycles is acceptable since the licensee has had no failures of the valves to stroke open in the past 10 years. The licensee has adequately considered the applicable NMP1 operational experience regarding the necessary verification and testing of the ERV solenoid capability and the prevention and detection of possible damage to the ERV pilot valves during dry stroke testing following installation. Therefore, all of the components necessary to manually actuate the ERVs will continue to be tested to demonstrate the functional capability of the valves, without the need to stroke test the valves on-line with system steam pressure. The NRC staff also notes that the current testing requirements could result in seat leakage of the ERVs during power operation. Excessive seat leakage could result in excessive suppression pool temperature and level or in unidentified drywell leakage.

The NRC staff has reviewed position verification alternative to ISTC-3700 and ISTC-5111 and finds that with the proposed alternative, the valve position is adequately verified. As previously noted, the current dry stroke test with no backpressure will result in damage to the pilot valve assembly. To prevent valve damage, the licensee will secure the pilot valve operating lever and pilot valve stem in the open position while locally observing the solenoid actuator plunger movement in conjunction with observing the control room indication. The proposed alternative will verify that solenoid actuator operation, and indirectly that the pilot valve position is accurately indicated. Therefore, the NRC staff finds that the proposed position verification alternative meets the intent of ASME OM Code requirements and is acceptable.

The NRC staff has reviewed stroke time test alternative to ISTC-5113 and ISTC-5114 and finds that with the proposed alternative, the valve stroke time is adequately measured and the results are compared to a pre-established reference value. Currently, the ASME OM Code-2004 required testing for the six ERVs is satisfied by manually stroking open each ERV with reactor at pressure. As previously noted, the proposed alternative will allow testing of main valves at an offsite facility. A pilot valve assembly and a solenoid actuator, both representative of the components used at the plant will be installed at the test facility to allow the testing of the main valve. The test conditions at the test facility are similar to those normal operating conditions in the plant. Therefore, the NRC staff finds that the proposed alternative captures the valve stroke testing and the stroke time test data required by ASME OM Code-2004, and therefore is acceptable.

-9 The NRC staff finds that the proposed alternative testing of the ERVs and associated components provides reasonable assurance that the valves will continue to operate when called upon to perform their safety-related function. Therefore, the NRC staff finds that the proposed alternative testing frequency and methods to those required by the ASME OM Code 2004 Edition is acceptable.

4.0 CONCLUSION

Based on the above evaluation, the NRC staff concludes that licensee's proposed alternative request RR-ADS-VR-01 will provide an acceptable level of quality and safety for the main steam ERVs, PSV-01-102A thru 102F. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(i), and is in compliance with the ASME OM Code requirements. All other ASME OM Code requirements for which relief was not specifically requested and approved in the subject request for relief remain applicable. Therefore, this alternative RR-ADS-VR-01 is authorized for the remainder of the fourth 10-year 1ST interval pursuant to 10 CFR 50.55a(a)(3)(i) on the basis that this alternative will provide an acceptable level of quality.

Principal Contributor: J. Huang, NRR Date: September 28, 2011

September 28, 2011 Mr. Thomas A. Lynch Vice President Nine Mile Point Nine Mile Point Nuclear Station, LLC P.O. Box 63 Lycoming, NY 13093 SUB~'ECT: NINE MILE POINT NUCLEAR STATION, UNIT NO.1 - REQUEST FOR ALTERNATIVE: AUTOMATIC DEPRESSURIZATION SYSTEM (ADS)-VR-01 FOR THE TESTING OF MAIN STEAM ELECTROMATIC RELIEF VALVES ASSOCIATED WITH THE FOURTH 10-YEAR INSERVICE TESTING INTERVAL (TAC NO. ME4848)

Dear Mr. Lynch:

By letter dated September 29,2010, Agencywide Documents Access and Management System (ADAMS) Accession No. ML102800415), Nine Mile Point Nuclear Station, LLC (NMPNS, the licensee), submitted a relief request to the Nuclear Regulatory Commission (NRC), requesting to use an alternative to certain American Society of Mechanical Engineers, Code for Operation and Maintenance of Nuclear Power Plants (ASME 01\11 Code), inservice testing (1ST) requirements pertaining to testing of the main steam Electromatic Relief Valves (ERVs). The licensee's request seeks relief from performing certain stroke testing of the main steam ERVs, PSV-01-102A thru 102F. Specifically, pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Section 55a(a)(3)(i), the licensee requested to use the proposed alternative, ADS-VR-01, on the basis that the alternative provides an acceptable level of quality and safety.

The NRC staff has reviewed the subject request, and concludes that the proposed alternative provides an acceptable level of quality and safety. Therefore, the NRC staff authorizes the proposed alternative in accordance with 10 CFR 50.55a(a)(3)(i) for the licensee's fourth 10 year 1ST interval. The results of the NRC staff's review are provided in the enclosed safety evaluation.

If you have any questions regarding this approval, please contact Richard Guzman, at 301-415-1030 or Richard.Guzman@nrc.gov.

Sincerely,

/raj Nancy L. Salgado, Chief Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-220

Enclosure:

As stated cc w/encl: Distribution via Listserv DISTRIBUTION:

PUBLIC RidsN rrPM RGuzman RidsN rrLASLittle RidsNrrDciCptb RidsOGCRp LPLI-1 R/F RidsRgn'llVIailCenter JHuang, NRR RidsN rrAcrsAcnw&mMailCenter Accession Number: ML112660001 'SE Input provided by memo No substantial changes made.

OFFICE LPL 1-1/PM LPL 1-1/LA CPTB/BC LPL1-1/BC NAME RGuzman SLittie AMcMurtray* NSalgado DATE 9/26/11 9/26/11 7/22/11 9/28/11 OFFICIAL RECORD COPY