ML13156A368
| ML13156A368 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 06/04/2013 |
| From: | Borton K Exelon Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML13156A368 (14) | |
Text
10 CFR 50.90 10 CFR 2.390 June 4, 2013 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Peach Bottom Atomic Power Station, Units 2 and 3 Facility Operating License Nos. DPR-44 and DPR-56 NRC Docket Nos. 50-277 and 50-278
Subject:
Extended Power Uprate License Amendment Request - Supplement 4 Response to Request for Additional Information - Extended Power Uprate
Reference:
- 1. Exelon letter to the NRC, License Amendment Request -
Extended Power Uprate, dated September 28, 2012 (ADAMS Accession No. ML122860201)
- 2. NRC letter to Exelon, Request for Additional Information Regarding License Amendment Request for Extended Power Uprate (TAC Nos. ME9631 and ME9632), dated April 26, 2013 (ADAMS Accession No. ML13106A126)
- 3. Exelon letter to the NRC, License Amendment Request -
Extended Power Uprate - Supplement 3, dated May 24, 2013 In accordance with 10 CFR 50.90, Exelon Generation Company, LLC (EGC) requested amendments to Facility Operating License Nos. DPR-44 and DPR-56 for Peach Bottom Atomic Power Station (PBAPS) Units 2 and 3, respectively (Reference 1). Specifically, the proposed changes would revise the Renewed Operating Licenses to implement an increase in rated thermal power from 3514 megawatts thermal (MWt) to 3951 MWt.
During their technical review of the application, the NRC Staff identified the need for additional information. Reference 2 provided the Requests for Additional Information (RAI) from eight NRC review branches. The EGC response to those RAIs, with the exception of three questions from the Electrical Engineering Branch, was provided in Reference 3.
This letter addresses the remaining questions from Reference 2.
EPU LAR Supplement 4 Response to Requests for Additional Information June 4,2013 Page 2 of 2 EGC has reviewed the information supporting a finding of no significant hazards consideration and the environmental consideration provided to the U. S. Nuclear Regulatory Commission in Reference 1. The supplemental information provided in this submittal does not affect the bases for concluding that the proposed license amendment does not involve a significant hazards consideration. Further, the additional information provided in this submittal does not affect the bases for concluding that neither an environmental impact statement nor an environmental assessment needs to be prepared in connection with the proposed amendment.
In accordance with 10 CFR 50.91, "Notice for public comment; State consultation,"
paragraph (b), EGC is notifying the Commonwealth of Pennsylvania and the State of Maryland of this application by transmitting a copy of this letter along with the non-proprietary attachments to the deSignated State Officials.
There are no regulatory commitments contained in this letter.
Should you have any questions concerning this letter, please contact Mr. David Neff at (610) 765-5631.
I declare under penalty of perjury that the foregoing is true and correct. Executed on the 4th day of June.
Respectfully, Kevin F. Borton Manager, Licensing - Power Uprate Exelon Generation Company, LLC
Attachment:
- 1. Response to Request for Additional Information - EEEB cc: USNRC Region I, Regional Administrator w/attachments USNRC Senior Resident Inspector, PBAPS w/attachments USNRC Project Manager, PBAPS w/attachments R. R. Janati, Commonwealth of Pennsylvania w/o proprietary attachments S. T. Gray, State of Maryland w/o proprietary attachments
Attachment 1 Peach Bottom Atomic Power Station Units 2 and 3 NRC Docket Nos. 50-277 and 50-278 Response to Request for Additional Information - EEEB
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 1 Response to Request for Additional Information Electrical Engineering Branch By letter dated September 28, 2012, Exelon Generation Company, LLC (Exelon) submitted a license amendment request for Peach Bottom Atomic Power Station (PBAPS), Units 2 and 3. The proposed amendment would authorize an increase in the maximum power level from 3514 megawatts thermal (MWt) to 3951 MWt. The requested change, referred to as an extended power uprate (EPU), represents an increase of approximately 12.4 percent above the current licensed thermal power level.
The NRC staff has reviewed the information supporting the proposed amendment and by letter dated April 26, 2013 (NRC Accession No. ML13106A126) has requested information to clarify the submittal. The responses to questions 4 through 15 were submitted on May 24, 2013. Additional time was requested to provide the responses to EEEB questions 1 through 3. The responses to those questions are provided below.
EEEB RAI-1 In Table 2.3-1 of Attachment 4 to the application dated September 28, 2012, the licensee provides the normal, design-basis accident (DBA) and total radiation requirements for rooms at PBAPS. For the environmental qualification (EQ) zones/areas, provide, in table form, a list of components and their respective qualification levels and parameters (i.e., temperature, pressure, humidity, chemical spray, submergence, and radiation) that shows that the EQ limits remain bounding under EPU conditions for normal operation, accident (loss-of-coolant accident (LOCA), main steam line break (MSLB)/high-energy line break (HELB)), and post-accident. Include the existing EQ limits in your response and show how EQ margins (e.g., temperature, pressure, radiation, etc.) are being maintained. Provide more detail with regard to the statement made on page 2-124 of Attachment 4 to the application dated September 28, 2012, about the margin evaluation complying with the Institute of Electrical and Electronics Engineers (IEEE) 323-1974 (Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations).
RESPONSE
Table 1 summarizes the changes to EQ environmental parameters due to EPU.
Changes are discussed in more detail below.
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 2 Table 1 Summary of EPU Impact on EQ DBA Environmental Parameters (Note 1)
IMPACT OF EPU Environmental Parameter Inside Containment Outside Containment Temperature, Normal No change No change Increased by scaling factor Increased by scaling factor Radiation, Normal of 1.1423 of 1.1423 No change in peak temperature (340°F);
No change except for Temperature, Accident change to post-DBA RWCU rooms (Note 2) temperature profile described below Changed from 47.8 to 48.7 Pressure, Accident No change psig Humidity, Accident No change No change Spray, Accident No Change N/A Submergence, Accident No Change No change Increased by scaling factor Increased by scaling factor Radiation, Accident of 1.1423 of 1.1423 Notes:
- 1) Accident means loss of coolant accident (LOCA), main steam line break (MSLB), or high energy line break (HELB), as applicable to each area.
- 2) During the reviews performed for EPU a deficiency was noted in the RWCU HELB analysis. The RWCU HELB analysis was therefore re-performed using bounding values that enveloped both current (pre-EPU) and EPU operating conditions. Table 3 shows that the equipment qualification limit bounds the DBA peak temperature in these rooms.
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 3 DBA Temperature inside Containment Figure 2.3-1 of Attachment 4 to the application shows the current Drywell EQ temperature profile and revised EPU Drywell temperature profile for 101 days post-accident. The profiles differ only during the first three hours where the EPU profile duration at peak temperature of 340°F increased. All equipment and commodities have been re-evaluated and remain qualified for the EPU Drywell temperature profile. The EPU EQ temperature evaluation does not affect the Current Licensed Thermal Power (CLTP) margins. EPU does not affect the peak temperature requirement and therefore, the EQ temperature margins at CLTP conditions are maintained.
DBA Pressure inside Containment Figure 2.6-6 of Attachment 4 to the LAR application shows the bounding EPU drywell pressure profile. Peak pressure increased from 47.8 psig (62.5 psia) to 48.7 psig (63.4 psia). All equipment and commodities were re-evaluated with respect to the EPU peak pressure of 48.7 psig. The evaluation determined that EQ qualification post-EPU was maintained and the remaining margins exceeded the required IEEE-323-1974, 10%
margin. Table 2 shows that the qualification limit bounds the postulated accident pressure with sufficient margin.
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 4 Table 2: Evaluation of Pressure Qualification of EQ Equipment and Commodities in the Drywell Qualification Margin Equipment Limit [psig] (Note 1)
AVCO Solenoid Valves 62 27%
NDT International Acoustic Monitors 61.3 25%
PYCO RTDs and Thermocouples 115 136%
Pyle National Plug Connectors 105 115%
General Atomic Radiation Detectors 77 58%
GE Electrical Penetrations 124 154%
Buchanan Terminal Blocks 113 132%
GE Terminal Blocks 103 111%
Weidmuller Terminal Blocks 113 132%
Amp Terminal Lugs 74 51%
ITT Surprenant Power Cable 113 132%
Okonite Power Cable 112 129%
Rockbestos Cable 105 115%
Patel Conduit Seals 100 105%
H2/O2 Analyzer 68 39%
EGS Grayboot Connectors 81 66%
Insulated Splices (Raychem Kits) 66 35%
EGS Quick Disconnects 77 58%
Limitorque Motor Operated Valves 79.1 62%
Namco Position Switches 70 43%
ASCO Solenoid Valves, Trip Coils, and 110 48%
Pressure Switches UCI Electrical Tape 62 27%
Brand-Rex Cable 100 105%
Notes:
- 1) Margin is calculated based on gauge pressure relative to the modified EQ pressure requirement of 48.7 psig (63.4 psia).
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 5 DBA Temperature Outside Containment Because the PBAPS EPU is a constant pressure EPU, the consequences of postulated HELBs remains unchanged. However, during the reviews performed for EPU, a deficiency was noted in the RWCU HELB analysis. The RWCU HELB analysis was therefore re-performed using bounding values that enveloped both current (pre-EPU) and EPU operating conditions. Table 3 identifies the rooms with EQ equipment impacted by an RWCU HELB and presents both the peak EPU accident (HELB) temperature and the qualification temperature limit for EQ equipment and commodities located in the room. Table 3 shows that the qualification limit bounds the postulated accident temperature.
Table 3-LOCA/HELB Temperature Evaluation Outside Containment Room Qualification Peak EPU Accident Room Name Number Limit (°F) Temperature (°F)
RWCU Valve 400 (Unit 2) 340 213 Compartment 403 (Unit 2) Operating Area 207 177 444 (Unit 3) Operating Area 207 177 RWCU Valve 447 (Unit 3) 340 213 Compartment Radiation Environment Inside & Outside Containment Table 4 identifies each type of equipment and commodity included in the PBAPS EQ Program along with the EPU EQ total integrated dose (TID) for relevant plant locations and the qualification limit. The EPU EQ TID is the sum of the normal dose, accident dose, and 10% margin on accident dose (in accordance with IEEE-323-1974 recommendations). The difference between the qualification limit and the EPU EQ TID reflects available excess margin. Table 4 shows that all equipment and commodities remain qualified for EPU operating conditions.
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 6 Table 4: Evaluation of Radiation Qualification of EQ Equipment and Commodities EPU EQ TID Rooms Qualification Equipment [rads]
(Note 1) Limit [rads]
(Note 2)
AVCO Solenoid Valves PC/OC 1.50E+08 1.56E+08 (U02, U06, and U14 series)
AVCO Solenoid Valves (models 6910-010, 6910- PC/OC 8.73E+07 1.07E+08 020, C-54505 only)
Rosemount Trip Units OC 1.02E+05 2.20E+05 Rosemount Pressure Transmitters (Model OC 3.88E+06 2.62E+07 1153B)
GE Control Station OC 1.14E+07 3.9E+07 Agastat Relays OC 1.02E+05 2.0E+05 Static-O-Ring Pressure OC 3.90E+06 1E+07 Switches Cutler Hammer MCC OC 2.89E+05 1.4E+06 PC 1.87E+08 2.00E+08 NDT International Acoustic Monitors OC 1.02E+05 5.35E+05 Target Rock Solenoid OC 2.90E+05 2.27E+07 Valves (76EE series only)
Target Rock Solenoid 4.80E+07 OC 4.48E+07 Valves PC 1.92E+08 2.2E+08 PYCO RTDs and Thermocouples OC 4.36E+07 1E+08 ITT Barton Differential Pressure Switches OC 4.36E+07 5.00E+07 (580A/583A series only)
ITT Barton Differential Pressure Switches OC 4.36E+07 5.0E+07 (Model 764/352 only)
ITT Barton Differential Pressure Switches OC 1.37E+05 3.0E+06 (Models 288/ 289A only)
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 7 EPU EQ TID Rooms Qualification Equipment [rads]
(Note 1) Limit [rads]
(Note 2)
Atkomatic Solenoid Valves OC 2.12E+06 2.68E+06 Reliance ECCS Fan OC 4.36E+07 1.0E+08 Motors Brown Boveri Load OC 2.89E+05 1E+06 Centers Valcor Solenoid Valves OC 4.27E+07 5.9E+07 GE Radiation Elements OC 1.68E+03 1.7E+05 General Atomic Radiation PC 1.92E+08 2.0E+08 Detectors GE Electrical Penetrations PC 8.70E+07 1E+08 Foxboro Pressure OC 2.90E+05 3.0E+06 Transmitters HPCI System Equipment OC 6.89E+06 8E+06 Masoneilan Electropneumatic OC 1.95E+06 1.12E+07 Transducer Manual Transfer Switch OC 1.02E+05 2.9E+05 Y-Panels and Associated OC 1.02E+05 1.2E+06 Transformers Barksdale Pressure Switch OC 3.88E+06 4.4E+06 PC/OC Components 1.92E+08 2E+08 in contact H2/O2 Analyzer with PC air Components in contact 3.86E+06 6.1E+06 with SC air 4.6E+07 GE 4 kV Pump Motors & (motor)
OC 4.36E+07 Associated Cables 1.0E+08 (cable)
Fuses and Fuse Holders OC 6.89E+06 1.0E+07
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 8 EPU EQ TID Rooms Qualification Equipment [rads]
(Note 1) Limit [rads]
(Note 2)
Limitorque Motor Operated PC/OC 1.22E+08 1.96E+08 Valves Namco Position Switches PC/OC 1.14E+08 2E+08 ASCO (Solenoid Valves PC/OC 1.50E+08 2.00E+08 and Trip Coils only)
ASCO (Pressure Switches OC 4.27E+07 2.0E+08 only)
Pyle National Plug PC 1.92E+08 2.0E+08 Connectors (Note 3)
Buchanan Terminal Blocks (Model NQB, Series 100) PC 1.94E+08 2.0E+08 (Note 3)
Buchanan Terminal Blocks (Models 416 and 430) OC 2.89E+05 3E+05 (Note 3)
GE Terminal Blocks PC 1.92E+08 2.2E+08 (Note 3)
Marathon Terminal Blocks OC 4.48E+07 2.5E+09 (Note 3)
Weidmuller Terminal PC 1.42E+08 2.0E+08 Blocks (Note 3)
Amp Terminal Lugs PC 1.92E+08 2.59E+08 (Note 3)
Scotch Insulating Tape OC 4.36E+07 6.2E+07 (Note 3)
GE SIS Cable (Note 3) PC/OC 1.00E+08 1E+08 ITT Surprenant Power PC 1.92E+08 2.56E+08 Cable (Note 3)
Okonite Power Cable PC 1.92E+08 2.0E+08 (Note 3)
Rockbestos Cable PC 1.17E+08 2.0E+08 (Firewall III) (Note 3)
Rockbestos Cable (coaxial cable, Pyrotrol, and SR) PC 1.94E+08 2.0E+08 (Note 3)
Patel Conduit Seals PC 1.94E+08 2.0E+08 (Note 3)
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 9 EPU EQ TID Rooms Qualification Equipment [rads]
(Note 1) Limit [rads]
(Note 2)
Jefferson Coaxial Cable OC 1.05E+07 2E+08 (Note 3)
Anaconda Instrument and OC 2.89E+05 3.0E+07 Power Cable (Note 3)
EGS Grayboot Connectors PC 2.05E+08 2.08E+08 (Note 3)
Insulated Splices (Raychem Kits, NMCK-8 OC 4.48E+07 5E+07 only) (Note 3)
Insulated Splices (Raychem Kits except PC 1.92E+08 2.0E+08 NMCK-8) (Note 3)
EGS Quick Disconnects PC 1.92E+08 2.0E+08 (Note 3)
UCI Electrical Tape PC 1.92E+08 2.0E+08 (Note 3)
Brand-Rex Cable (Note 3) PC 1.92E+08 2E+08 Notes:
- 1) PC indicates primary containment. OC indicates Outside Primary Containment. SC indicates Secondary Containment
margin on accident dose.
- 3) Items marked by this note are commodity items that are qualified for various plant areas based on the worst-case location (either Drywell, worst-case Reactor Building room having EQ equipment, or specific applications).
Margin The EPU EQ evaluation applied the IEEE-323-1974 margin recommendations for relevant environmental parameters. The recommended margins (10%) on pressure and accident dose are specifically accounted for as discussed previously. The EQ evaluation applied IEEE-323-1974 recommended temperature margin of either +15°F degree or other alternate means. The EPU EQ evaluation applied a 10% margin to the post accident operating time.
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 10
==
Conclusion:==
EQ for safety related electrical equipment is based on MSLB outside containment, HELB and /or LOCA conditions and their resultant temperature, pressure, humidity, submergence and radiation consequences. All equipment remains qualified for post EPU parameters.
EEEB RAI-2 On page 2-124 of Attachment 4 to the application dated September 28, 2012, the licensee states that limited life components (less than 60 years) are addressed within the PBAPS EQ program as warranted. Provide a list of all EQ Program equipment that will have a limited life due to increase in temperature, pressure, humidity, and radiation at EPU conditions. Confirm that there is no EQ equipment that needs to be replaced prior to EPU implementation.
RESPONSE
There is no equipment that will have a limited life due to increase in temperature, pressure, humidity, radiation at EPU conditions. There is no EQ equipment that needs to be replaced prior to EPU implementation. The environmental qualification of EQ equipment is not impacted by EPU changes.
EEEB RAI-3 In Figure 2.3-1 of Attachment 4 to the application dated September 28, 2012, the licensee presented the current EQ temperature profile and revised post-EPU EQ temperature profile, for the drywell (DW). Update this profile for the equipment to show that the equipment remains qualified for the temperature in the DW under EPU conditions. Provide a containment LOCA/MSLB Accident Pressure profile curve vs. the plant EQ profile.
RESPONSE
Drywell Temperature Profile:
The Small Steam Line Break (SSLB) is the limiting event for DW temperature. The figure below provides the composite profile of PBAPS SSLB drywell temperature and the bounding EQ temperature profile. The only impact of the EPU on the EQ temperature profile was an increase in the duration of the peak temperature. This impact was evaluated as described in response to EEEB RAI-1 above. The results of the EQ evaluation concluded that the environmental qualification of EQ equipment was not impacted by EPU and therefore remains qualified for post-EPU operation. The SSLB temperatures profiles are also shown in Figure 2.6-10 of Attachments 4 and 6 of the PBAPS EPU LAR.
EPU LAR Supplement 4 - RAI - EEEB June 4, 2013 Page 11 Drywell Peak Pressure:
As was discussed in the NRC-EGC clarification call on April 17, 2013, the response provides the limiting component relative to peak DW pressure. Figure 2.6-6 of Attachments 4 and 6 of the PBAPS EPU LAR show the bounding EPU DW pressure profile. Peak DW pressure increased from 47.8 psig to 48.7 psig as shown in the Figure 2.6-6 and Table 2.6-1 of Attachments 4 and 6 of the PBAPS EPU LAR. As discussed above in the response to EEEB RAI-1 above, all equipment and commodities were evaluated with respect to the EPU peak pressure and remain qualified for post EPU operation. The lowest qualification peak pressure for any EQ component is 61.3 psig and the associated margin is 25%. This exceeds the 10% margin to peak pressure recommended by IEEE-323-1974.