ML093221030

Electronic Transmission, Draft RAI Regarding Response to Generic Letter 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray System

ML093221030
Person / Time
Site:	Oyster Creek
Issue date:	11/18/2009
From:	Geoffrey Miller Plant Licensing Branch 1
To:	Chernoff H Plant Licensing Branch 1
Miller G, NRR/DORL/LPL1-2, 415-2481
References
GL-08-001
Download: ML093221030 (5)

Text

November 18, 2009 MEMORANDUM TO: Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM: G. Edward Miller, Project Manager /ra/

Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

SUBJECT:

OYSTER CREEK NUCLEAR GENERATING STATION - ELECTRONIC TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING RESPONSE TO GENERIC LETTER 2008-01, MANAGING GAS ACCUMULATION IN EMERGENCY CORE COOLING, DECAY HEAT REMOVAL, AND CONTAINMENT SPRAY SYSTEMS The attached draft request for additional information (RAI) was transmitted by electronic transmission on November 18, 2009 to Mr. Kenneth M. Nicely, at Exelon Generation Company, LLC (Exelon, the licensee). This draft RAI was transmitted to facilitate the technical review being conducted by the Nuclear Regulatory Commission (NRC) staff and to support a conference call with Exelon in order to clarify the licensees response to Generic Letter 2008-01.

The draft RAI is related to the licensees response dated April 11, 2008, and supplement dated October 14, 2008. The draft questions were sent to ensure that they were understandable, the regulatory basis was clear, and to determine if the information was previously docketed.

Additionally, review of the draft RAI would allow Exelon to evaluate and agree upon a schedule to respond to the RAI. This memorandum and the attachment do not represent an NRC staff position.

Docket Nos. 50-219

Enclosure:

As stated

November 18, 2009 MEMORANDUM TO: Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM: G. Edward Miller, Project Manager /ra/

Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

SUBJECT:

OYSTER CREEK NUCLEAR GENERATING STATION - ELECTRONIC TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING RESPONSE TO GENERIC LETTER 2008-01, MANAGING GAS ACCUMULATION IN EMERGENCY CORE COOLING, DECAY HEAT REMOVAL, AND CONTAINMENT SPRAY SYSTEMS The attached draft request for additional information (RAI) was transmitted by electronic transmission on November 18, 2009 to Mr. Kenneth M. Nicely, at Exelon Generation Company, LLC (Exelon, the licensee). This draft RAI was transmitted to facilitate the technical review being conducted by the Nuclear Regulatory Commission (NRC) staff and to support a conference call with Exelon in order to clarify the licensees response to Generic Letter 2008-01.

The draft RAI is related to the licensees response dated April 11, 2008, and supplement dated October 14, 2008. The draft questions were sent to ensure that they were understandable, the regulatory basis was clear, and to determine if the information was previously docketed.

Additionally, review of the draft RAI would allow Exelon to evaluate and agree upon a schedule to respond to the RAI. This memorandum and the attachment do not represent an NRC staff position.

Docket Nos. 50-219

Enclosure:

As stated DISTRIBUTION:

Public RidsNrrPMGMiller LPL1-2 R/F Accession No.: ML093221030 *Via memorandum LPL1-2/PM SRXB/BC NAME GEMiller GCranston*

DATE 11/18/2009 11/9/09 OFFICIAL RECORD COPY

DRAFT REQUEST FOR ADDITIONAL INFORMATION OYSTER CREEK NUCLEAR GENERATING STATION RESPONSE TO GENERIC LETTER 2008-01 DOCKET NO. 50-219 By letter dated April 11, 2008, as supplemented by letter dated October 14, 2008 (Agencywide Document Access and Management System (ADAMS) Accession Nos.

ML081020758 and ML082880706, respectively), Exelon Generation Company (Exelon or the licensee) provided a response to Generic Letter (GL) 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems, for the Oyster Creek Nuclear Generating Station (Oyster Creek).

Specifically, Exelons response discusses the emergency core cooling, decay heat removal, and containment spray systems with regards to compliance with the current licensing and design bases and applicable regulatory requirements, and suitable design, operational, and testing control measures are in place for maintaining compliance. To complete its review, the Nuclear Regulatory Commission (NRC) staff requests responses to the following request for additional information.

Guidance on NRC staff expectations is provided in Reference 1. Nuclear Energy Institute (NEI) guidance is provided in Reference 2. The NRC staff recommends that DNC consult Reference 1 when responding to the following questions:

1. In Reference 4, Exelon states that the impact of the voids on system operability is evaluated on a case-by-case basis, with acceptable void volumes being determined as part of the evaluation. Please provide a description of your void volume determination methods and how said voids will be quantified and recorded. Additionally, please provide a comparison of your method against the criteria given in Reference 5

2. In Reference 4, Exelon states that the evaluation process includes consideration of the impact that the void could have on pump operation, water hammer pressure transients, etc. Please describe the monitoring of pump operation in all modes and specialized monitoring of appropriate plant parameters during shutdown operation, including reduced inventory and mid-loop operation.

3. Clarify the meaning of acceptable and inaccessible as used in Reference 4.

Include a discussion of piping within containment, piping that requires scaffolding to reach, and piping in posted radiation areas.

4. In Reference 4, Exelon states that its review of system design and operating practices concluded that the systems are adequately monitored and tested for potential gas intrusion mechanisms. Provide additional details regarding measures to guard against gas intrusion because of inadvertent draining, system realignments, incorrect maintenance procedures, or other evolutions.

5. Provide a brief description of actions that will be taken if surveillance criteria are not met. Include any post-surveillance activities, such as gas volume trending

and procedural checks, used in response to the failure to meet void acceptance criteria.

6. Provide a discussion of the control and revision of work packages due to change in maintenance work scope, including review and reauthorization of the package and any new temporary procedures.

7. Although training was not explicitly discussed in the GL (Reference 3), it is considered a necessary part of applying procedures and other activities in addressing the subject issues. Please provide a brief description of the training to be employed.

REFERENCES

1. Ruland, William H., Preliminary Assessment of Responses to Generic Letter 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems, and Future NRC Staff Review Plans, NRC letter to James H. Riley, Nuclear Energy Institute, ML091390637, May 28, 2009.

2. Riley, James H., Generic Letter (GL) 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Contain Spray Systems Evaluation and 3 Month Response Template, Letter to Administrative Points of Contact from Director, Engineering, Nuclear Generation Division, Nuclear Energy Institute, Enclosure 2, Generic Letter 2008-01 Response Guidance, March 20, 2008.

3. Case, Michael J., NRC Generic Letter 2008-01: Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems, Letter from Director, Division of Policy and Rulemaking, Office of Nuclear Regulation, NRC, ML072910759, January 11, 2008.

4. Jury, Keith R., Nine-Month Response to NRC Generic Letter 2008-01, Letter to Document Control Desk, NRC, from Vice President-Licensing and Regulatory Affairs, Exelon Generation Company, LLC, AmerGen Energy Company, LLC, ML082880706, October 14, 2008.

5. Revision 2 to NRC Staff Criteria for Gas Movement in Suction Lines and Pump Response to Gas, ML090900136, March 26, 2009.