ML16340A002

NRR E-mail Capture - (External_Sender) Byron Station Response to SPF Instrumentation Environmental Questions Regarding the Mitigating Strategies Final Integrated Plan

ML16340A002
Person / Time
Site:	Byron
Issue date:	12/02/2016
From:	Zurawski L Exelon Corp
To:	John Hughey Japan Lessons-Learned Division
References
Download: ML16340A002 (3)

Text

NRR-PMDAPEm Resource From: Zurawski, Lisa M:(GenCo-Nuc) <lisa.zurawski@exeloncorp.com>

Sent: Friday, December 02, 2016 2:50 PM To: Hughey, John Cc: Distel, David J:(GenCo-Nuc); Merkle, Donald:(GenCo-Nuc); Spitzer, Douglas J:(GenCo-Nuc); Kuchenbecker, James P:(Contractor - GenCo-Nuc)

Subject:

[External_Sender] NRC question about qualification temperature of the Spent Fuel Pool Instrumentation The NRC questioned:

Area heatup limits provided to NRC for this area are based on the design basis room maximum limits of 133°F normal and 140°F abnormal conditions, not Extended Loss of Alternating Current Power (ELAP) calculated temperatures, and these values are very close to the Westinghouse Spent Fuel Pool Instrumentation (SFPI) qualification temperature of 140F under the Fukushima ELAP conditions.

The NRC is requesting a qualitative engineering judgement evaluation to support the 140F value for SFPI qualification being adequate when the design basis abnormal temperature is 140°F in this area. NRC requested a discussion of the ELAP condition and whether FLEX-backed ventilation is or could be provided and whether area doors are or could be provided.

Byron Stations Response:

Spent Fuel Pool Level instrument components are located in EQ Zone A11. Per Calculation BYR01-068, Revision 2 (Environmental Parameters of EQ Zones), EQ Zone A11 is a Mild Zone with maximum normal temperature of 133 °F. EQ Zone A11 does not have a temperature for accident conditions, however, Note 14 of the calculation addresses conditions of Loss of Coolant Accident (LOCA) and Loss of Offsite Power (LOOP) as follows: Under conditions of LOCA and LOOP, maximum temperature will increase during 2-hour period due to HVAC systems operation using available electrical power sources and with consideration of equipment heat loads for event mitigation. Maximum temperatures during this condition are: 140 Degrees F for Zone A11. The bounding value of 140 °F is determined in Calculation VA-102, Revision 5 (Auxiliary Building Energy Load Calculations for Elevations 330 346, 364, 383 401 & 426 in Abnormal Condition), which determines temperatures for multiple locations within EQ Zone A11, as follows:

EQ Zone A11 Locations Unit 1 and Unit 2 Electrical Penetration Area (El 426) Calculated Temperature = 127.1 °F Unit 1 and Unit 2 Electrical Penetration Area (El 414) Calculated Temperature = 125.3 °F Unit 1 and Unit 2 Electrical Equipment Room (El 414) Calculated Temperature = 138.2 °F Unit 1 and Unit 2 Motor Driven Auxiliary Feedwater Pump Rooms Calculated Temperature = 135.8 °F Unit 1 and Unit 2 Diesel Driven Auxiliary Feedwater Pump Rooms Calculated Temperature = 133.0 °F SFP Level electronics are located as follows:

Primary SFP Level Loop: Unit 1 Auxiliary Building 426 Electrical Penetration Area, plant coordinates U-15 (Test Report 0FC-001, Rev 1 and Drawing 6E-1-3352, Rev CL)

Secondary SFP Level Loop: Unit 2 Auxiliary Building 426 Electrical Penetration Area, plant coordinates U-21 (Test Report 0FC-002, Rev 1 and Drawing 6E-2-3552, Sh 3, Rev BW)

Therefore, the Primary and Secondary SFP Level electronics are located in Unit 1 and Unit 2 Electrical Penetration Areas, El 426. The calculated temperature of this location is 127.1 °F during conditions of LOCA 1

and LOOP for a 2-hour period, which is below the stated 140 °F maximum temperature for Zone A11 (140 F bounds all locations above in EQ Zone A11).

The LOCA and LOOP conditions described above include heat loads from electrical equipment and liquid systems that will not exist during an ELAP. During an ELAP event, there will be no heat loads from electrical equipment or liquid systems in the area. The heat generated from the Spent Fuel Pool has to conduct to 426 Electrical Penetration Areas, which includes a 3 foot concrete wall. There is a significant heat sink in the 426 Electrical Penetration areas from the containment wall and surrounding Auxiliary Building walls. There is also a significant heat sink from the Fuel Handling Building walls and ceiling. Due to the lack of heat sources in the area of the instruments, barriers between the Fuel Handling Building and instrument areas, and the large heat sink that will dissipate heat, the 140 °F rating of the SFP Level instrumentation is adequate.

Lisa Zurawski Byron Station Principal Regulatory Engineer 815-406-2991 Lisa.Zurawski@exeloncorp.com This Email message and any attachment may contain information that is proprietary, legally privileged, confidential and/or subject to copyright belonging to Exelon Corporation or its affiliates ("Exelon"). This Email is intended solely for the use of the person(s) to which it is addressed. If you are not an intended recipient, or the employee or agent responsible for delivery of this Email to the intended recipient(s), you are hereby notified that any dissemination, distribution or copying of this Email is strictly prohibited. If you have received this message in error, please immediately notify the sender and permanently delete this Email and any copies.

Exelon policies expressly prohibit employees from making defamatory or offensive statements and infringing any copyright or any other legal right by Email communication. Exelon will not accept any liability in respect of such communications. -EXCIP 2

Hearing Identifier: NRR_PMDA Email Number: 3196 Mail Envelope Properties (DD36716564A86A4B8BFB3CA6B9EED3EFA8C3F28C)

Subject:

[External_Sender] NRC question about qualification temperature of the Spent Fuel Pool Instrumentation Sent Date: 12/2/2016 2:50:04 PM Received Date: 12/2/2016 2:50:08 PM From: Zurawski, Lisa M:(GenCo-Nuc)

Created By: lisa.zurawski@exeloncorp.com Recipients:

"Distel, David J:(GenCo-Nuc)" <David.Distel@exeloncorp.com>

Tracking Status: None "Merkle, Donald:(GenCo-Nuc)" <Donald.Merkle@exeloncorp.com>

Tracking Status: None "Spitzer, Douglas J:(GenCo-Nuc)" <douglas.spitzer@exeloncorp.com>

Tracking Status: None "Kuchenbecker, James P:(Contractor - GenCo-Nuc)" <James.Kuchenbecker@exeloncorp.com>

Tracking Status: None "Hughey, John" <John.Hughey@nrc.gov>

Tracking Status: None Post Office: exchm-ccc-21.exelonds.com Files Size Date & Time MESSAGE 4932 12/2/2016 2:50:08 PM Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received: