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{{#Wiki_filter:0311612009 U.S. Nuclear Regulatory Commission Operations Center Event Report Pa,-e I General Information or Other (PAR)Event# 44896 Rep Org: ABB INC. Notification Date ! Time: 03/11/2009 15:52 (EDT)Supplier:
ABB INC. Event Date / Time: 03/11/2009 (EDT)Last Modification:
03/16/2009 Region: 1 Docket #: City: Florence Agreement State: Yes County: License #: State: SC NRC Notified by: TERRY MALLOY Notifications:
ANTHONY DIMITRIADIS R1 HQ Ops Officer: DAN LIVERMORE REBECCA NEASE R2 Emergency Class: NON EMERGENCY JULIO LARA R3 10 CFR Section: THOMAS FARNHOLTZ R4 21.21 UNSPECIFIED PARAGRAPH RX PART 21 GROUP E-MAIL PART 21 NOTIFICATION
-DEFECTIVE HK AND K-LINE CIRCUIT BREAKER TENSION SPRINGS The identification of the subject component is as follows: ABB P/N 716359A00 Tension Spring. These springs are used in both HK (Medium Voltage) and K-Line (Low voltage) circuit breakers.
In the HK breaker, the spring is used on the racking mechanism to position the racking mechanism interlocking latch. In the K-Line circuit breaker, the spring resets the prop latch mechanism following a circuit breaker trip. Circuit breakers and spare parts procured from ABB between 04/23/2008 and 02/27/2009 may have suspect springs installed.
Nature of the deviation:
Micro-cracks in the base of the hooked end of the springs may result in failure of the springs after repetitive cycles. A broken spring could potentially affect the ability of a K-Line or HK breaker to reset and close after an opening operation.
Initial report of the nonconformance was generated on 02/11/2009 (NCR#68999JL), reporting that springs failed during mechanical life testing being performed on a K-Line breaker. These springs failed after approximately 2,800 cycles each.Given the large number of applications for the affected circuit breakers, ABB (Medium Voltage Service) cannot determine if the potential for a substantial safety hazard exists at any licensee's facility if a similar failure of the tension spring occurs. Licensees are requested to evaluate the history of inspections, maintenance practices, and circuit breaker operating cycles for K-Line breakers, and racking cycles for HK breakers to determine if the circuit breaker spring should be replaced immediately or at the next convenient maintenance opportunity.
ABB recommends that any suspect spring with greater than 1,400 operating cycles be replaced as soon as possible.Currently ABB is determining the affected licensees and will notify them on or about March 30, 2009.*** UPDATE FROM K. WELBORN TO P. SNYDER AT 0759 ON 3/16/2009
***/Aj~-
03/16/2009 U.S. Nuclear Regulatory Commission Operations Center Event Report Paze 2 General Information or Other (PAR)ABB updated the original report by providing a list of affected customers.
Event# 44896 Notified R1DO (DeFrancisco), R2DO (Nease), R3DO (Lara), and R4DO (Farnholtz).
Received at: 03/16/2009 07:59 All March 13, 2009 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001 FAX 301-816-5151
 
==Subject:==
Amended Report -- 10 C.F.R. Part 21 Notification of Deviation re- P/N 716539A00 Tension Springs
 
==Dear Sir or Madam:==
This amended report is submitted to provide the list of affected utilities who may have received a suspect component, report results of validation testing of replacement springs, and to correct a transposed part number of the subject component.
This letter is submitted in accordance with 10 C.F.R § 21.21(d)(3)(ii) with respect to a failure to comply with specifications associated with P/N 716539A00 Tension Springs procured as a conunercial grade item from Ace Wire Spring and Form, Inc., and dedicated by ABB from a Production nm of 1215 pieces produced April 18, 2008. The information below is provided in order to meet the specific reporting requirements set forth in 10 C.F.R. § 21.21(d)(4).
The notifying individual is Mr. Kelly Welbom, Plant Manager, ABB Inc., 2300 Mechanicsville Road, Florence, SC 29501.The identification of the Subject component is as follows: ABB P/N 716359A00 Tension Spring.These springs are used in both HK (Medium Voltage) and K-Line (Low Voltage) circuit breakers.
In the HK breaker, the spring is used on the racking mechanism to position the racking mechanism interlock latch. In the K-Line circuit breaker, the spring resets the prop latch mechanism following a circuit breaker trip. See photos below: ABB Inc.2300 MECHANICSVILLE FROAD FLORENCE, SC 29601 US3A MEDIUM VOLTAGE SE'VItE CIMIIINE (843i 4 13-485 rACSIMILE (84:3) 413-4850 A#B Circuit breakers and spare parts procured from ABB between 4/23/2008 and 2/27/2009 may have suspect springs installed.
Nature of the deviation:
Micro-cracks in the base of the hooked end of the springs may result in failure of the springs after repetitive cycles- A broken spring could potentially affect the ability of a K-Line or HK breaker to reset and close after an opening operation.
Initial report of the nonconformance was generated 2/11/2009 (NCR #68999JL), reporting springs failed during mechanical life testing being performed on a K-Line Breaker. Three springs failed after approximately 2800 cycles each.Metallurgical analysis of a failed spring concluded that the failure originated in pre-existing cracks in the bend area at the base of the fully formed round hook. Subsequent investigation at the vendor site determined that a production run in April 2008 was manufactured using a different method than prior production runs, in that the fully formed round end of the spring was made using a manual press instead of an automatic hydraulic/pneumatic press. The manual press forming cycle was significantly faster, in that the loop was formed in approximately one second, versus six seconds for the automatic press. Additionally, the manual forming operation was done after tempering and stress-relieving the spring, while the automatic forming occurred prior to tempering and stress relief.An additional issue was identified during the investigation in that the opposite end rectangular hook had tool marks from the forming operation that could result in premature spring failure. One spring failed after 6000 cycles in the concave bend area at this end. See photo below:<S..L+/-~V1Lt .r, .KtA,...,t,~tj2, -.ABS Inc.2300 MECHANICSVILLE ROAD FLORENCE, SC 29501 USA IVMEIUlUM VOL I PU QLr'vIl-FACSIMILE (W) 413-4850 ABB ABB is taking, or has taken, the following corrective actions: a. Promptly notify affected customers of the possibility of a failure of the springs as outlined.
This action is expected to be completed on or about March 20, 2009. The list of affected utilities is included as Attachment 1 to this report,.b. Reviewed historical procurement and inspection records associated with the subject part and vendor and determined that no previous defects were identified in the last five years, out of nearly nine thousand units received for both commercial and safety-related applications.
: c. Worked with our vendor, Ace Wire, to determine how future incidents can be prevented and developed quality assurance means to minimize the possibility of a recurrence.
As of March 9, 2009, tooling has been polished to minimize tooling marks, and the fully formed hook will be made using the automatic forming machine on future orders.d. A cycle test has been completed to compare springs produced before and after Ace Wire polished the hook forming tools to validate that the corrective actions are sufficient.
To date, 12,000 cycles on (20) springs have been completed, with no ftrther failures.Microscopic inspection has also been done that confirmed the tooling marks have been reduced.Given the large number of applications for the affected circuit breakers, ABB (Medium Voltage Service) cannot determine if the potential for a substantial safety hazard exists at any licensee's facility if a similar failure of the tension spring occurs. Licensees are requested to evaluate the history of inspections, maintenance practices, and circuit breaker operating cycles for K-Line breakers, and racking cycles for HK breakers to determine if the circuit breaker spring should be replaced immediately or at the next convenient maintenance opportunity.
ABB recommends that any suspect spring with greater than 1400 operating cycles be replaced as soon as possible.If you have any questions regarding this notice, please be so kind as to contact Mr. Kelly Welbom directly at 843-413-4777.
Sincerely Yours, Kelly Wd born Plant Manager Attachment
-List of Affected Customers ABB Inc.2300 MECNANICSVILLE ROAD MEDIUM VOLTAGE SERVICE PHONE (843) 413-4700-. rI r ..nef,- I "CA FACSIMILE (S43) 413-4850 rUdmr-(IN'.,, -' C,3i, List of Affected Customers Customer Address CiyStateZip PO#AMERICAN ELECTRIC 500 CIRCLE DRIVE BUCHANAN, MI 49107-193n 01530045, 01531073 POWER NUCLEAR GENERATION GROUP APS PALO VERDE NUCLEAR PO BOX 0 2034 PHOENIX, AZ 85072-2034 500521364, 4500498099, GENERATING 500527149 CONSTELLATION POWER P0 BOX 17340 BALTIMORE, MD21297-1340 7709388 SOURCE GENERATIONING DOMINION RESOURCES SERVICES, INC INNSBROOK TECHNICAL CENTER 5000 DOMINION BOULEVARD GLEN ALLEN, VA 23060 45582792,45602110, 45605512, 70164459, 70164459 00103937,00104266, DUKE ENERGY CAROLINAS LLC MAIL CODE EC05P P. 0. BOX 1006 CHARLOTTE, N C 28201-1 006'00 103937, 00104266, 00105219,00105571,00110451 00112742, 00114608 DUKE ENERGY CAROLINAS LLC ENTERGY OPERATIONS
-MAIL CODE ECOSN P. 0. BOX 1006 5485 US HIGHWAY 61 CHARLOTTE, NC 28201-1006
__ _ _i.SAINT FRANCISVILLE.
LA 70775 RIVER BEND ENTERGY OPERATIONS, INC P.O. BOX 31995 JACKSON, MS 39286-1995 KENNETT SQUARE, PA 19348 EXELON NUCLEAR COMPANYiP, 0. BOX 160 10183919,10173757 10199578 90 027099 00112003,00416044.
02215024, 0221646, 02216527 J. ____FLORIDA POWER & LIGHT 1700 UNIVERSE BLVD JUNO "'BEACH, FL33408 COMPANY FPL ENERGY, SEABROOK, LLC (FPLE)P.O. BOX 14000 P.O. BOX 300 1EABROOK, NH 03874 FPL TURKEY POINT NUCLEAR 36-4 10 MILES EAST OF U. S.ROUTE 1 ON PALM DRIVE' '-I !1-LUttILIA UI I Y -L 330U3 1 3UU1O FP& L ST. LUCIE 1CM 700 UNIVERSE BRA/D JUNO BEACH. FL 33408 109705 700 UNIVERSE BLVD--- i 1501 ARDMORE BLVD SUITE 401 PITTSBURGH PA 15221 PERRY NUCLEAR POWER PLANT PRAIRIE ISLAND NUCLEAR GENERATING STATION PROGRESS ENERGY BRUNSWICK NUCLEAR PLANT PROGRESS ENGERY PSEG NUCLEAR,LLC PSE& G SOUTHERN CALIFORNIA EDISON SOUTHERN NUCLEAR OPERATING COMPANY STP NUCLEAR OPERATING COMPANY TVA NUCLEAR 10 CENTER ROAD 1717 WAKONADE DRIVE, EAST I PERRY, OH 44091 WELCH, MN 55089-9642 SOUTHPORT, NORTH CAROLINA 28461[CRYSTAL RIVER, FLORIDA 34428 4500094325 45281324, 45281614, 45281882, 45286477, 45288472,452291696,45291572_
23558 00328498, 00376675 403182]NC HY 87 CRYSTAL RIVER 3 NUCLEAR PLANT 15760 W POWER LINE STREET MAIL STOP S99 P. 0. BOX 236 PO BOX 23-6 I HANCOCKS BRIDGE, NJ 08038 4500443577,4500453869, 4500458263,4500485966, 4500479912, 4500490477 HANCOCKSd-'
--IDGE, NJ 08038 1 4500461872, 4500464158, 449013,4500498099, P. 0. BOX 128 tSAN CLEMENTE, CA 92674-I0128 P. O. BOX 1295 BIRMINGHAM, AL 35201 Po BOX 289 WADSWORTH, TX 77483 1101 MARKET STREET CHATTANOOGA, TN 37402-12801 4500499257 6X2T8909, 6F222901 A015 7082861, 7079308&001, 7084838 106437 I'0005794400202 I Attachment to ABB Letter to NRC Dated March 13, 2009}}

Revision as of 13:43, 14 October 2018

Part 21 Notification - Defective Hk and K-Line Circuit Breaker Tension Springs
ML090761188
Person / Time
Site: Millstone, Calvert Cliffs, Dresden, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Palo Verde, Perry, Catawba, Saint Lucie, Watts Bar, Hope Creek, Sequoyah, Byron, Arkansas Nuclear, Braidwood, Prairie Island, Seabrook, Brunswick, Surry, North Anna, Turkey Point, River Bend, Crystal River, Vogtle, Waterford, Farley, South Texas, San Onofre, Cook, Quad Cities, Zion, Bellefonte, McGuire, LaSalle  Constellation icon.png
Issue date: 03/11/2009
From: Malloy T
ABB
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
44896, P/N 716359A00, FOIA/PA-2011-0157
Download: ML090761188 (6)


Text

0311612009 U.S. Nuclear Regulatory Commission Operations Center Event Report Pa,-e I General Information or Other (PAR)Event# 44896 Rep Org: ABB INC. Notification Date ! Time: 03/11/2009 15:52 (EDT)Supplier:

ABB INC. Event Date / Time: 03/11/2009 (EDT)Last Modification:

03/16/2009 Region: 1 Docket #: City: Florence Agreement State: Yes County: License #: State: SC NRC Notified by: TERRY MALLOY Notifications:

ANTHONY DIMITRIADIS R1 HQ Ops Officer: DAN LIVERMORE REBECCA NEASE R2 Emergency Class: NON EMERGENCY JULIO LARA R3 10 CFR Section: THOMAS FARNHOLTZ R4 21.21 UNSPECIFIED PARAGRAPH RX PART 21 GROUP E-MAIL PART 21 NOTIFICATION

-DEFECTIVE HK AND K-LINE CIRCUIT BREAKER TENSION SPRINGS The identification of the subject component is as follows: ABB P/N 716359A00 Tension Spring. These springs are used in both HK (Medium Voltage) and K-Line (Low voltage) circuit breakers.

In the HK breaker, the spring is used on the racking mechanism to position the racking mechanism interlocking latch. In the K-Line circuit breaker, the spring resets the prop latch mechanism following a circuit breaker trip. Circuit breakers and spare parts procured from ABB between 04/23/2008 and 02/27/2009 may have suspect springs installed.

Nature of the deviation:

Micro-cracks in the base of the hooked end of the springs may result in failure of the springs after repetitive cycles. A broken spring could potentially affect the ability of a K-Line or HK breaker to reset and close after an opening operation.

Initial report of the nonconformance was generated on 02/11/2009 (NCR#68999JL), reporting that springs failed during mechanical life testing being performed on a K-Line breaker. These springs failed after approximately 2,800 cycles each.Given the large number of applications for the affected circuit breakers, ABB (Medium Voltage Service) cannot determine if the potential for a substantial safety hazard exists at any licensee's facility if a similar failure of the tension spring occurs. Licensees are requested to evaluate the history of inspections, maintenance practices, and circuit breaker operating cycles for K-Line breakers, and racking cycles for HK breakers to determine if the circuit breaker spring should be replaced immediately or at the next convenient maintenance opportunity.

ABB recommends that any suspect spring with greater than 1,400 operating cycles be replaced as soon as possible.Currently ABB is determining the affected licensees and will notify them on or about March 30, 2009.*** UPDATE FROM K. WELBORN TO P. SNYDER AT 0759 ON 3/16/2009

      • /Aj~-

03/16/2009 U.S. Nuclear Regulatory Commission Operations Center Event Report Paze 2 General Information or Other (PAR)ABB updated the original report by providing a list of affected customers.

Event# 44896 Notified R1DO (DeFrancisco), R2DO (Nease), R3DO (Lara), and R4DO (Farnholtz).

Received at: 03/16/2009 07:59 All March 13, 2009 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001 FAX 301-816-5151

Subject:

Amended Report -- 10 C.F.R. Part 21 Notification of Deviation re- P/N 716539A00 Tension Springs

Dear Sir or Madam:

This amended report is submitted to provide the list of affected utilities who may have received a suspect component, report results of validation testing of replacement springs, and to correct a transposed part number of the subject component.

This letter is submitted in accordance with 10 C.F.R § 21.21(d)(3)(ii) with respect to a failure to comply with specifications associated with P/N 716539A00 Tension Springs procured as a conunercial grade item from Ace Wire Spring and Form, Inc., and dedicated by ABB from a Production nm of 1215 pieces produced April 18, 2008. The information below is provided in order to meet the specific reporting requirements set forth in 10 C.F.R. § 21.21(d)(4).

The notifying individual is Mr. Kelly Welbom, Plant Manager, ABB Inc., 2300 Mechanicsville Road, Florence, SC 29501.The identification of the Subject component is as follows: ABB P/N 716359A00 Tension Spring.These springs are used in both HK (Medium Voltage) and K-Line (Low Voltage) circuit breakers.

In the HK breaker, the spring is used on the racking mechanism to position the racking mechanism interlock latch. In the K-Line circuit breaker, the spring resets the prop latch mechanism following a circuit breaker trip. See photos below: ABB Inc.2300 MECHANICSVILLE FROAD FLORENCE, SC 29601 US3A MEDIUM VOLTAGE SE'VItE CIMIIINE (843i 4 13-485 rACSIMILE (84:3) 413-4850 A#B Circuit breakers and spare parts procured from ABB between 4/23/2008 and 2/27/2009 may have suspect springs installed.

Nature of the deviation:

Micro-cracks in the base of the hooked end of the springs may result in failure of the springs after repetitive cycles- A broken spring could potentially affect the ability of a K-Line or HK breaker to reset and close after an opening operation.

Initial report of the nonconformance was generated 2/11/2009 (NCR #68999JL), reporting springs failed during mechanical life testing being performed on a K-Line Breaker. Three springs failed after approximately 2800 cycles each.Metallurgical analysis of a failed spring concluded that the failure originated in pre-existing cracks in the bend area at the base of the fully formed round hook. Subsequent investigation at the vendor site determined that a production run in April 2008 was manufactured using a different method than prior production runs, in that the fully formed round end of the spring was made using a manual press instead of an automatic hydraulic/pneumatic press. The manual press forming cycle was significantly faster, in that the loop was formed in approximately one second, versus six seconds for the automatic press. Additionally, the manual forming operation was done after tempering and stress-relieving the spring, while the automatic forming occurred prior to tempering and stress relief.An additional issue was identified during the investigation in that the opposite end rectangular hook had tool marks from the forming operation that could result in premature spring failure. One spring failed after 6000 cycles in the concave bend area at this end. See photo below:<S..L+/-~V1Lt .r, .KtA,...,t,~tj2, -.ABS Inc.2300 MECHANICSVILLE ROAD FLORENCE, SC 29501 USA IVMEIUlUM VOL I PU QLr'vIl-FACSIMILE (W) 413-4850 ABB ABB is taking, or has taken, the following corrective actions: a. Promptly notify affected customers of the possibility of a failure of the springs as outlined.

This action is expected to be completed on or about March 20, 2009. The list of affected utilities is included as Attachment 1 to this report,.b. Reviewed historical procurement and inspection records associated with the subject part and vendor and determined that no previous defects were identified in the last five years, out of nearly nine thousand units received for both commercial and safety-related applications.

c. Worked with our vendor, Ace Wire, to determine how future incidents can be prevented and developed quality assurance means to minimize the possibility of a recurrence.

As of March 9, 2009, tooling has been polished to minimize tooling marks, and the fully formed hook will be made using the automatic forming machine on future orders.d. A cycle test has been completed to compare springs produced before and after Ace Wire polished the hook forming tools to validate that the corrective actions are sufficient.

To date, 12,000 cycles on (20) springs have been completed, with no ftrther failures.Microscopic inspection has also been done that confirmed the tooling marks have been reduced.Given the large number of applications for the affected circuit breakers, ABB (Medium Voltage Service) cannot determine if the potential for a substantial safety hazard exists at any licensee's facility if a similar failure of the tension spring occurs. Licensees are requested to evaluate the history of inspections, maintenance practices, and circuit breaker operating cycles for K-Line breakers, and racking cycles for HK breakers to determine if the circuit breaker spring should be replaced immediately or at the next convenient maintenance opportunity.

ABB recommends that any suspect spring with greater than 1400 operating cycles be replaced as soon as possible.If you have any questions regarding this notice, please be so kind as to contact Mr. Kelly Welbom directly at 843-413-4777.

Sincerely Yours, Kelly Wd born Plant Manager Attachment

-List of Affected Customers ABB Inc.2300 MECNANICSVILLE ROAD MEDIUM VOLTAGE SERVICE PHONE (843) 413-4700-. rI r ..nef,- I "CA FACSIMILE (S43) 413-4850 rUdmr-(IN'.,, -' C,3i, List of Affected Customers Customer Address CiyStateZip PO#AMERICAN ELECTRIC 500 CIRCLE DRIVE BUCHANAN, MI 49107-193n 01530045, 01531073 POWER NUCLEAR GENERATION GROUP APS PALO VERDE NUCLEAR PO BOX 0 2034 PHOENIX, AZ 85072-2034 500521364, 4500498099, GENERATING 500527149 CONSTELLATION POWER P0 BOX 17340 BALTIMORE, MD21297-1340 7709388 SOURCE GENERATIONING DOMINION RESOURCES SERVICES, INC INNSBROOK TECHNICAL CENTER 5000 DOMINION BOULEVARD GLEN ALLEN, VA 23060 45582792,45602110, 45605512, 70164459, 70164459 00103937,00104266, DUKE ENERGY CAROLINAS LLC MAIL CODE EC05P P. 0. BOX 1006 CHARLOTTE, N C 28201-1 006'00 103937, 00104266, 00105219,00105571,00110451 00112742, 00114608 DUKE ENERGY CAROLINAS LLC ENTERGY OPERATIONS

-MAIL CODE ECOSN P. 0. BOX 1006 5485 US HIGHWAY 61 CHARLOTTE, NC 28201-1006

__ _ _i.SAINT FRANCISVILLE.

LA 70775 RIVER BEND ENTERGY OPERATIONS, INC P.O. BOX 31995 JACKSON, MS 39286-1995 KENNETT SQUARE, PA 19348 EXELON NUCLEAR COMPANYiP, 0. BOX 160 10183919,10173757 10199578 90 027099 00112003,00416044.

02215024, 0221646, 02216527 J. ____FLORIDA POWER & LIGHT 1700 UNIVERSE BLVD JUNO "'BEACH, FL33408 COMPANY FPL ENERGY, SEABROOK, LLC (FPLE)P.O. BOX 14000 P.O. BOX 300 1EABROOK, NH 03874 FPL TURKEY POINT NUCLEAR 36-4 10 MILES EAST OF U. S.ROUTE 1 ON PALM DRIVE' '-I !1-LUttILIA UI I Y -L 330U3 1 3UU1O FP& L ST. LUCIE 1CM 700 UNIVERSE BRA/D JUNO BEACH. FL 33408 109705 700 UNIVERSE BLVD--- i 1501 ARDMORE BLVD SUITE 401 PITTSBURGH PA 15221 PERRY NUCLEAR POWER PLANT PRAIRIE ISLAND NUCLEAR GENERATING STATION PROGRESS ENERGY BRUNSWICK NUCLEAR PLANT PROGRESS ENGERY PSEG NUCLEAR,LLC PSE& G SOUTHERN CALIFORNIA EDISON SOUTHERN NUCLEAR OPERATING COMPANY STP NUCLEAR OPERATING COMPANY TVA NUCLEAR 10 CENTER ROAD 1717 WAKONADE DRIVE, EAST I PERRY, OH 44091 WELCH, MN 55089-9642 SOUTHPORT, NORTH CAROLINA 28461[CRYSTAL RIVER, FLORIDA 34428 4500094325 45281324, 45281614, 45281882, 45286477, 45288472,452291696,45291572_

23558 00328498, 00376675 403182]NC HY 87 CRYSTAL RIVER 3 NUCLEAR PLANT 15760 W POWER LINE STREET MAIL STOP S99 P. 0. BOX 236 PO BOX 23-6 I HANCOCKS BRIDGE, NJ 08038 4500443577,4500453869, 4500458263,4500485966, 4500479912, 4500490477 HANCOCKSd-'

--IDGE, NJ 08038 1 4500461872, 4500464158, 449013,4500498099, P. 0. BOX 128 tSAN CLEMENTE, CA 92674-I0128 P. O. BOX 1295 BIRMINGHAM, AL 35201 Po BOX 289 WADSWORTH, TX 77483 1101 MARKET STREET CHATTANOOGA, TN 37402-12801 4500499257 6X2T8909, 6F222901 A015 7082861, 7079308&001, 7084838 106437 I'0005794400202 I Attachment to ABB Letter to NRC Dated March 13, 2009