ML090500720

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Submittal of Relief Requests Associated with the Third Inservice Testing Interval
ML090500720
Person / Time
Site: Limerick  Constellation icon.png
Issue date: 02/18/2009
From: Cowan P
Exelon Generation Co, Exelon Nuclear
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML090500720 (15)
v • d • e


Text

Exelon Nuclear www.exeloncorp.com 200 Exelon Way Nuclear Kennett Square, PA 19348 10 CFR 50.55a February 18, 2009 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Limerick Generating Station, Units 1 and 2 Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353

Subject:

Submittal of Relief Requests Associated with the Third Inservice Testing Interval Attached for your review are relief requests associated with the third Inservice Testing (1ST)

Interval for Limerick Generating Station (LGS), Units 1 and 2. The third interval of the LGS, Units 1 and 21ST program complies with the ASME OM Code, 2004 Edition. The third ten-year interval for LGS, Units 1 and 2 is scheduled to begin on January 8,2010 and conclude on January 7,2020. We request your approval by February 18, 2010.

There are no regulatory commitments contained within this letter.

If you have any questions concerning this letter, please contact Mr. Tom Loomis at (610) 765-5510.

Sincerely,

<tP rf~1fJl1 Pamela B. Cowan Director - Licensing & Regulatory Affairs Exelon Generation Company, LLC

Attachment:

1) Relief Requests Associated with the Third Ten-Year Interval for Limerick Generating Station, Units 1 and 2 cc: S. J. Collins, Regional Administrator, Region I, USNRC E. M. DiPaolo, USNRC Senior Resident Inspector, LGS P. J. Bamford, Project Manager [LGS] USNRC R. R. Janati, Commonwealth of Pennsylvania

Relief Requests Associated with the Third Ten-Year Interval for Limerick Generating Station, Units 1 and 2 Relief Request No. Description GPRR-5, Revision 0 Use of Code Case OMN-6 Alternative Rules for Digital Instruments 11-PRR-1, Revision 1 Use of Code Case OMN-9 ESW Pump Test Using Pump Curves 90-PRR-1, Revision 1 Installed Pump Instrumentation Greater Than 2%

GVRR-5, Revision 3 Series-Parallel Check Valve Testing 47-VRR-2, Revision 0 Control Rod Drive Scram Valves and Check Valves

RELIEF REQUEST NO. GPRR-5, REVISION 0 Use of Code Case O:MN-6 Alternative Rules for Digital Instruments Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

1. AS:ME Code Components Affected:

All ASME Code Class 2 and 3 pumps, except skid mounted, in the scope of the Limerick 1ST Program. .

2. Applicable Code Edition:

The applicable code edition is the ASME OM Code, 2004 Edition. The new interval is scheduled to begin on January 8, 2010 and conclude on January 7,2020.

3. Applicable Code Requirement(s):

Paragraph ISTB-3510(b)(2) requires that the reference value does not exceed 70% of the calibrated range for digital instruments. ISTB-3510(b)(2), "digital instruments shall be selected such that the reference value does not exceed 70% of the calibrated range of the instrument."

4. Reason for Request

Pursuant to 10 CPR 50.55a, "Codes and Standards," paragraph (a)(3)(i), relief is requested from the requirement of ASME OM Code ISTB-3510(b)(2). This request is to allow the use of ASME Code Case OMN-6, "Alternate Rules for Digital Instruments."

Code Case OMN-6 allows the use of digital instruments where the reference value does not exceed 90% of the calibrated range of the instrument. LGS, Units 1 and 2 will implement the 2004 Edition of the ASME OM Code for its third 10-year Interval and intends to use this Code Case.

5. Proposed Alternative and Basis for Use:

OMN-6 allows reading up to 90% of the calibrated range of the instrument versus the referenced applicable requirement of 70% from the ASME OM Code, 2004 Edition, Paragraph ISTB-3510(b)(2). OMN-6 permits the use of a greater usable range of the permanently installed instruments at LGS, Units 1 and 2.

NUREG-1482, Revision 1, Section 5.5 states that "The NRC has accepted Code Case OMN-6 as specified in Regulatory Guide 1.192, which allows each digital instrument to be such that the reference values do not exceed 90 percent of the calibrated range of the instrument."

Page 1 of2

RELIEF REQUEST NO. GPRR-5, REVISION 0 Use of Code Case Ol\1N-6 Alternative Rules for Digital Instruments Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

Use of Code Case OMN-6, approved by the NRC in Regulatory Guide 1.192, will provide at least equivalent instrumentation accuracy requirements for the required pump testing parameters to be measured in the 1ST program and will provide results consistent with code requirements.

This will provide adequate assurance of acceptable pump performance.

Using the provisions of this relief request as an alternative to the specific requirements of ISTB-35l0(b)(2) identified above will provide adequate indication of pump performance and continue to provide an acceptable level of quality and safety. Therefore, pursuant to 10 CPR 50.55a(a)(3)(i), relief is requested from the specific ISTB requirements identified in this request.

6. Duration of Proposed Alternative:

Duration will be for the third ten-year interval for LGS, Units 1 and 2, which is scheduled to begin on January 8, 2010 and conclude on January 7,2020.

7. Precedents:
1) Letter from H. Chernoff (U. S. Nuclear Regulatory Commission) to D. Christian (Dominion Nuclear Connecticut, Inc.), "Millstone Power Station, Units 2 and 3 - Relief Requests for the Fourth 10-Year and Third 10-Year Pump and Valve Inservice Testing Programs, (TAC NOS.

MD7763 THROUGH MD777l)," dated October 24, 2008 (Pump Relief Request P-002)

2) Letter from D. Terao (U. S. Nuclear Regulatory Commission) to J. Keenan (Pacific Gas and Electric Company), "Diablo Canyon Power Plant, Unit Nos. 1 and 2 - Approval of Relief Requests P-RRl, P-RR2, AND P-RR3 For the Third 10-Year Pump and Valve Inservice Testing Program Interval (TAC NOS. MC6632 AND MC6633)," dated January 30,2006 (Pump Relief Request P-RR3)

Page 2 of2

RELIEF REQUEST NO. II*PRR*l, REVISION 1 Use of Code Case 01\1N*9 ESW Pump Test Using Pump Curves Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

1. ASlVIE Code Components Affected:

Pump(s): Emergency Service Water OAP548 OCP548 OBP548 ODP548 Type: Vertical Line Shaft Driver: Motor Group: A Code Class: 3

2. Applicable Code Edition:

The applicable code edition is the ASME OM Code, 2004 Edition. The new interval is scheduled to begin on January 8, 2010 and conclude on January 7,2020.

3. Applicable Code Requirement(s):

ISTB-5221 and 5223 require inservice testing to be conducted with the pump operating at specified test reference conditions. Further, ISTB-5221(b) and 5223(b) require the resistance of the system be varied until the flow rate or differential pressure equals its reference value, at which point the other parameter (differential pressure or flow rate) be determined and compared to its reference value.

4. Reason for Request

Pursuant to 10 CFR 50.55a, "Codes and Standards," paragraph (a)(3)(i), relief is requested to use Code Case OMN-9, "Use of a Pump Curve for Testing," which is not applicable to the ASME OM Code, 2004 Edition.

The Emergency Service Water (ESW) System includes a large number of variable heat loads. In addition, the temperature of the system is seasonally dependent and can vary significantly.

Therefore, it is extremely difficult to vary the resistance of the system to establish flow or differential pressure conditions at any fixed reference point. Operations personnel would need to assume local manual control of automatic room cooler valves and equipment modulating valves.

This requires access to Emergency Core Cooling System (ECCS) room coolers and other safety related equipment causing numerous entries into Radiological Controlled Areas (RCAs) to adjust flow to a fixed reference point in order to perform this quarterly test, which will also result in additional dose.

Establishment of multiple sets of reference values would not improve the capability to set either variable at a fixed point.

Page 1 of3

RELIEF REQUEST NO. II-PRR-l, REVISION 1 Use of Code Case O:MN-9 ESW Pump Test Using Pump Curves Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--AltemativeProvides Acceptable Level of Quality and Safety--

1ST of these pumps has used reference curves during the preceding Ten Year Intervals.

5. Proposed Alternative and Basis for Use:

In order to monitor the ESW pumps for degradation and assure their operational readiness, reference curves as described in Code Case OMN-9 will be used for inservice testing. Pump testing is performed quarterly using these pump curves. Flow, normally in the range of 3000 to 4100 gpm, is measured and total dynamic head is calculated from the pump discharge pressure and the level of the Spray Pond (i.e., suction). The test point is then compared to the pump curve and determined to be within the acceptance range of Table ISTB-5221-1 (0.95 to 1.10 Pr for Group A Test or 0.95 to 1.03 Pr for Comprehensive Test), which is also plotted on the pump curve.

Corrective action, if required, shall meet the requirements of ISTB-6200.

These pump curves were prepared during flow balancing activities shortly before commercial operation of LGS, Unit 2. They include many empirical data points taken over the entire operating range of the pumps, essentially from shutoff head to approximately 1.5 times the maximum flow required for safe shutdown or accident mitigation. Manufacturer's representatives witnessed and concurred with the development of these curves. These curves exceed the requirements of OMN-9 for a minimum of 3 data points and at least one data point for each 20% of the maximum pump curve range.

Vibration readings are taken in accordance with ISTB-3540. In addition to the Code-required vibration readings, several additional readings are taken and analyzed in accordance with the LGS Predictive Maintenance Program. Since these pumps show little variation in vibration over their normal operating range, the acceptance criteria for vibration testing complies with the requirements of Table ISTB-5221-1.

LGS, Units 1 and 2 will meet the conditions as stated in Regulatory Guide 1.192, June 2003, as applicable.

The reference pump curves for inservice testing are considered acceptable in meeting the intent of the ASME O&M Code-2004 Paragraphs ISTB-5221 and 5223.

6. Duration of Proposed Alternative:

Duration will be for the third ten-year interval for LGS, Units 1 and 2, which is scheduled to begin on January 8, 2010 and conclude on January 7,2020.

Page 2 of3

RELIEF REQUEST NO. II-PRR-l, REVISION 1 Use of Code Case Ol\tlN-9 ESW Pump Test Using Pump Curves Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

7. Precedents:
1) Letter from S. Coffin (U. S. Nuclear Regulatory Commission) to D. A. Christian (Virginia Electric Power Company), "Surry Power Station, Units 1 and 2 - American Society of Mechanical Engineers Inservice Testing Program (TAC NOS. MC0120 Through MC0146),"

dated July 2, 2004

2) Letter from H. Chernoff (U. S. Nuclear Regulatory Commission) to D. Christian (Dominion Nuclear Connecticut, Inc.), "Millstone Power Station, Units 2 and 3 - Relief Requests for the Fourth 10-Year and Third 10-Year Pump and Valve Inservice Testing Programs, (TAC NOS.

MD7763 THROUGH MD7771)," dated October 24, 2008 (P-004)

3) Letter from J. Clifford (U. S. Nuclear Regulatory Commission) to J. Hutton (PECO Energy Company), "Second 10-Year Interval Pump and Valve Inservice Testing Program Relief Requests Nos. 90-PRR-1, Revision 0; GPRR-3, Revision 2; 11-PRR-1, Revision 0; GVRR-4, Revision 2; GVRR-5, Revision 2; 20-VRR-1, Revision 2; and 41-VRR-6, Revision 0, for Limerick Generating Station, Units 1 and 2 (TAC NOS. MA8077 and MA8079)," dated November 28, 2000 Page 3 of3

RELIEF REQUEST NO. 90-PRR-1, REVISION 1 Installed Pump Instrumentation Greater Than 2 %

Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

1. ASME Code Components Affected:

Pump(s): Main Control Room OAP162 Chilled Water OBP162 Type: Centrifugal Driver: Motor Group: B Code Class: 3

2. Applicable Code Edition:

The applicable code edition is the ASME OM Code, 2004 Edition. The new interval is scheduled to begin on January 8, 2010 and conclude on January 7,2020.

3. Applicable Code Requirement(s)

Paragraph ISTB-3510(a) requires that instrument accuracy be within the limits of Table 3510-1, which specifies an accuracy requirement of +/-2% of full-scale for analog flow instruments.

Paragraph ISTB- 3510(b)(1) requires that the full-scale range of each analog instrument be not greater than three times the reference value.

4. Reason for Request

Pursuant to 10 CPR 50.55a, "Codes and Standards," paragraph (a)(3)(i), relief is requested from the requirement of ASME OM Code ISTB-3510(a). For instruments to be in compliance with the Code, both requirements stated above must be met, individually, for each instrument. The combination of the two requirements (i.e., accuracy equal to +/-2% of full-scale and full scale being up to 3 times the reference value) yields a permissible inaccuracy of +/-6% of the reference value.

The permanently installed flow instruments shown in the table below are calibrated to an accuracy greater than the +/-2% full-scale limit.

5. Proposed Alternative and Basis for Use:

As a proposed alternative, LGS, Units 1 and 2 propose to use the currently installed analog instruments for measurement of flow for the identified equipment. Although these instruments do not meet Code requirements, they provide better indication accuracy at the reference value than that which is permitted by the Code.

Page 1 of2

RELIEF REQUEST NO. 90-PRR-l, REVISION 1 Installed Pump Instrumentation Greater Than 2 %

Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

Section 5.5.1 of NUREG 1482, Revision 1, states that the staff may grant relief when the combination of the range and accuracy yields a reading at least equivalent to the reading achieved from instruments that meet the Code requirements (i.e., up to +/-6 percent).

The following table shows the instrument accuracy and full scale range of the flow instruments used to conduct inservice testing of the pumps listed above. The resulting instrument tolerance and indicated accuracy are calculated and also listed in the table. The indicated accuracy at the reference value is shown to be within the permissible 6 percent.

INSTRUMENT REFERENCE INSTRUMENT INSTRUMENT INSTRUMENT INDICATED NUMBER VALUE RANGE (FULL SCALE) ACCURACY TOLERANCE ACCURACY FI-90-034A 600 0-800 3.08% 24.64 4.11%

FI-90-034B 600 0-800 3.04% 24.32 4.05%

Based on Section 5.5.1 of NUREG 1482, Revision 1, and the information provided herein, the existing permanently installed pump instrumentation is considered acceptable in meeting the intent of the ASME OM Code-2004 Paragraphs ISTB 3510(a) and 3510(b)(l).

6. Duration of Proposed Alternative:

Duration will be for the third ten-year interval for LGS, Units 1 and 2, which is scheduled to begin on January 8, 2010 and conclude on January 7,2020.

7. Precedents
1. Letter from T. Boyce (U. S. Nuclear Regulatory Commission) to R. Duncan II (Carolina Power & Light Company), "Shearon Harris Nuclear Plant, Unit 1- Relief Request AF-PR-1 for the Third 10-Year Inservice Inspection Interval (TAC NO. MD3894)," dated July 16, 2007 (Relief Request AF-PR-1)
2. Letter from H. Chernoff (U. S. Nuclear Regulatory Commission) to W. Levis (PSEG Nuclear LLC), "Safety Evaluation of Relief Requests for the Third 10-Year Interval of the Inservice Testing Program for Hope Creek Generating Station (TAC NOS. MD3300, MD3301, MD3337, MD3338, MD3353, AND MD3354)," dated April 5, 2007 (P-01)
3. Letter from J. Clifford (U. S. Nuclear Regulatory Commission) to J. Hutton (PECO Energy Company), "Second 10-Year Interval Pump and Valve Inservice Testing Program Relief Requests Nos. 90-PRR-1, Revision 0; GPRR-3, Revision 2; 11-PRR-1, Revision 0; GVRR-4, Revision 2; GVRR-5, Revision 2; 20-VRR-1, Revision 2; and 41-VRR-6, Revision 0, for Limerick Generating Station, Units 1 and 2 (TAC NOS. MA8077 and MA8079)," dated November 28, 2000 Page 2 of2

RELIEF REQUEST NO. GVRR-5, REVISION 3 Series-Parallel Check Valve Testing Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

1. ASl\1E Code Components Affected:

Valve(s): 49-1017 49-2017 49-1018 49-2018 49-1F068 49-2F068 49-1F081 49-2F081 55-1025 55-2025 55-1026 55-2026 55-1F080 55-2F080 55-1F094 55-2F094 Category: C Code Class: 2

2. Applicable Code Edition:

The applicable code edition is the ASME OM Code, 2004 Edition. The new interval is scheduled to begin on January 8, 2010 and conclude on January 7,2020.

3. Applicable Code Requirement(s):

ISTC-5221(a)(1) requires check valves that have a safety function in both the open and closed directions shall be exercised by initiating flow and observing that the obturator has traveled to either the full open position or to the position required to perform its intended function(s), and verify that on cessation or reversal of flow, the obturator has traveled to the seat.

4. Reason for Request

Pursuant to 10 CPR 50.55a, "Codes and Standards," paragraph (a)(3)(i), relief is requested from the requirement of ASME OM Code ISTC-5221(a)(l). These Class 2 check valves open to equalize pressure between the HPCI and RCIC turbine exhaust lines and the Suppression Chamber as the steam in the piping collapses following turbine operation (e.g., following inservice pump testing). They close to prevent admission of unquenched turbine exhaust steam into the Suppression Chamber.

These valves are installed in a series-parallel arrangement and are not provided with any type of auxiliary operators or mechanical exercisers. The configuration used is similar in principle to the one-out-of-two, taken-twice logic arrangements used in the Reactor Protection System, and provides for a high degree of reliability on the basis that no single valve failure would prevent the valves from fulfilling their function as a group. Each of the valves in the two sets of parallel check valves can be verified in the closed position by reverse flow testing. The piping configuration does not allow for individual testing of these valves to the open position by forward flow testing. See diagrams below, typical for Units 1 and 2.

Page 1 of3

RELIEF REQUEST NO. GVRR-5, REVISION 3 Series-Parallel Check Valve Testing Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

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RELIEF REQUEST NO. GVRR-5, REVISION 3 Series-Parallel Check Valve Testing Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

5. Proposed Alternative and Basis for Use:

As a proposed alternative, forward flow testing will be performed quarterly on all 4 valves, as a unit. All four valves will be declared inoperable if the 4-valve unit fails to allow the required forward flow. Reverse flow testing of each parallel set of check valves (2 sets, 2 valves per set) will be performed quarterly. Both valves in the set will be declared inoperable if testing indicates that the valves do not close on reverse flow.

The configuration of these valves is similar in principle to the in-series check valve arrangement described in ISTC-5223 and NUREG-1482, Revision 1, Section 4.1.1, except that the addition of the parallel feature increases reliability while decreasing the ability to test the valves individually.

The LGS UFSAR does not take credit for use of the series-parallel configuration for fulfillment of the functions described above.

In the forward direction, testing of all four valves as a unit will verify that the configuration can prevent the formation of a vacuum in the exhaust piping as designed. In the reverse direction, there are sufficient test taps available to allow for the testing of each parallel set of check valves as a pair to verify closure on reverse flow. The installation of additional branch connections and valving to enable testing of these check valves individually would not increase the level of safety or provide assurance that the configuration would be capable of performing its intended functions.

Forward flow testing of all 4 valves as a unit, and reverse flow testing of each parallel set of check valves is considered an acceptable alternative for demonstrating the systems will perform their intended safety function.

6. Duration of Proposed Alternative:

Duration will be for the third ten-year interval for LGS, Units 1 and 2, which is scheduled to begin on January 8, 2010 and conclude on January 7,2020.

7. Precedents Letter from J. Clifford (U. S. Nuclear Regulatory Commission) to J. Hutton (PECO Energy Company), "Second 10-Year Interval Pump and Valve Inservice Testing Program Relief Requests Nos. 90-PRR-1, Revision 0; GPRR-3, Revision 2; 11-PRR-1, Revision 0; GVRR-4, Revision 2; GVRR-5, Revision 2; 20-VRR-1, Revision 2; and 41-VRR-6, Revision 0, for Limerick Generating Station, Units 1 and 2 (TAC NOS. MA8077 and MA8079)," dated November 28,2000 Page 3 of3

RELIEF REQUEST NO. 47*VRR*2, REVISION 0 Control Rod Drive Scram Valves and Check Valves Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

1. ASl\1E Code Components Affected:

Valves: Inlet and Outlet Scram Valves XV-47-1-26 (all 185 HCUs) XV-47-2-26 (all 185 HCUs)

XV-47-1-27 (all 185 HCUs) XV-47-2-27 (all 185 HCUs)

Category: B Type: Air Operated Valves: Scram Discharge Riser Check Valve 47-1-14 (all 185 HCUs) 47-2-14 (all 185 HCUs)

Cooling Water Check Valve 47-1-38 (all 185 HCUs) 47-2-38 (all 185 HCUs)

Category: C Type: Self-Actuated Code Class: 2

2. Applicable Code Edition:

The applicable code edition is the ASME OM Code, 2004 Edition. The new interval is scheduled to begin on January 8, 2010 and conclude on January 7,2020.

3. Applicable Code Reguirement(s):

Relief is requested from the following requirements:

ISTC-3510 requires that active Category B valves shall be exercised nominally every three months, except as provided by ISTC -3520, ISTC- 3540, ISTC-3550, ISTC-3570, ISTC-5221, and ISTC-5222.

ISTC-3560 requires valves with fail safe actuators be tested by observing the operation of the actuator upon loss of valve actuating power in accordance with the exercising frequency of ISTC-3510.

ISTC-5131(a) requires that active valves shall have their stroke time measured when exercised in accordance with ISTC-3500.

ISTC-3510 requires that active Category C check valves shall be exercised nominally every three months, except as provided by ISTC -3520, ISTC- 3540, ISTC-3550, ISTC-3570, ISTC-5221, and ISTC-5222.

Page 1 of3

RELIEF REQUEST NO. 47-VRR-2, REVISION 0 Control Rod Drive Scram Valves and Check Valves Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

ISTC-5221 (a)(2) requires check valves [47-1(2)-14] that have a safety function in only the open direction shall be exercised by initiating flow and observing that the obturator has traveled to either the full open position or to the position required to perform its intended function(s), and verify closure.

ISTC-5221(a)(3) requires check valves [47-1(2)-38] that have a safety function in only the close direction shall be exercised by initiating flow and observing that the obturator has traveled to at least the partially open position, and verify that on cessation or reversal of flow, the obturator has traveled to the seat.

4. Reason for Request

Pursuant to 10 CPR 50.55a, "Codes and Standards," paragraph (a)(3)(i), relief is requested to use the guidance provided in Generic Letter 89-04, Position 7. Generic Letter 89-04, Position 7 discusses alternative testing of individual scram valves for control rods in Boiling Water Reactors. Position 7 states that use of these alternatives to satisfy valve testing requirements should be documented in the 1ST Program. NUREG-1482, Revision 1, Section 1.3, states that specific relief is required to implement the positions of Generic Letter 89-04.

5. Proposed Alternative and Basis for Use:

Each of the valves listed above represents 1 of 185 CRD Hydraulic Control Unit (HCU) valves.

The air operated valves, XV-47-1(2)-26 and XV-47-1(2)-27, open on a signal from the Reactor Protection System to permit rapid insertion of the control rods (scram). Check valve 47-1(2)-14 is flow actuated as a result of XV-47-1(2)-27 opening. Reverse flow closure verification of 47-1(2)-

38 is demonstrated by normal control rod motion, which would not occur if this valve failed in the open position.

Generic Letter 89-04, Position 7 states that the rod scram test frequency identified in the facility Technical Specifications (TS) may be used as the valve testing frequency to minimize rapid reactivity transients and wear of the control rod drive mechanisms. In addition, it states that verifying control rod scram insertion time limits defined in the TS can be an acceptable alternate method of detecting valve degradation to the normal Code-required stroke time testing.

As a proposed alternative, testing will be performed in accordance with the requirements of TS 4.1.3.2. The TS requires control rod scram insertion time testing be performed with reactor coolant pressure greater than or equal to 950 psig and the rod drive pumps isolated from the accumulators as follows:

a. For all control rods prior to thermal power exceeding 40% of rated thermal power following core alterations or after a reactor shutdown that is greater than 120 days.

Page 2 of3

RELIEF REQUEST NO. 47-VRR-2, REVISION 0 Control Rod Drive Scram Valves and Check Valves Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i)

--Alternative Provides Acceptable Level of Quality and Safety--

b. For specifically affected individual control rods following maintenance on or modification to the control rod or control rod drive system which could affect the scram insertion time of those specific control rods, and
c. For at least 10% of the control rods, on a rotating basis, at least once per 120 days of power operation.

This testing meets or exceeds Code frequency requirements, since all valves will be tested per the TS at least once per fuel cycle.

6. Duration of Proposed Alternative:

Duration will be for the third ten-year interval for LGS, Units 1 and 2, which is scheduled to begin on January 8,2010 and conclude on January 7,2020.

7. Precedents:

None Page 3 of3

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