ML092600790

Electronic Transmission, Draft Request for Additional Information Regarding Response to Generic Letter 2008-01

ML092600790
Person / Time
Site:	Three Mile Island
Issue date:	09/21/2009
From:	Peter Bamford Plant Licensing Branch 1
To:	Chernoff H Plant Licensing Branch 1
Bamford, Peter J., NRR/DORL 415-2833
References
GL-08-001
Download: ML092600790 (4)

Text

September 21, 2009 MEMORANDUM TO: Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM: Peter Bamford, Project Manager /RA/

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

SUBJECT:

THREE MILE ISLAND, UNIT NO. 1 - ELECTRONIC TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING RESPONSE TO GENERIC LETTER 2008-01 The attached draft request for additional information (RAI) was transmitted by electronic transmission on September 17, 2009, to Mr. Ken 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 (if needed) with Exelon in order to clarify the licensees response to Generic Letter 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal and Containment Spray Systems. The draft RAI is related to the licensees submittals dated April 11, 2008, and 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. 50-289

Enclosure:

As stated

September 21, 2009 MEMORANDUM TO: Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM: Peter Bamford, Project Manager /RA/

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

SUBJECT:

THREE MILE ISLAND, UNIT NO. 1 - ELECTRONIC TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING RESPONSE TO GENERIC LETTER 2008-01 The attached draft request for additional information (RAI) was transmitted by electronic transmission on September 17, 2009, to Mr. Ken 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 (if needed) with Exelon in order to clarify the licensees response to Generic Letter 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal and Containment Spray Systems. The draft RAI is related to the licensees submittals dated April 11, 2008, and 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. 50-289

Enclosure:

As stated DISTRIBUTION:

Public RidsNrrPMThreeMileIsland Resource LPL1-2 R/F Accession No.: ML092600790 *via correspondence OFFICE LPL1-2/PM SRXB/BC NAME PBamford GCranston*

DATE 9/21/09 07/24/2009 OFFICIAL RECORD COPY

REQUEST FOR ADDITIONAL INFORMATION THREE MILE ISLAND NUCLEAR STATION, UNIT 1 GENNERIC LETTER 2008-01, MANAGING GAS ACCUMULATION IN EMERGENCY CORE COOLING, DECAY HEAT REMOVAL AND CONTAINMENT SPRAY SYSTEMS DOCKET NO. 50-289 By letters dated April 11, 2008 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML081020758), and October 14, 2008 (ADAMS Accession No. ML082880706), AmerGen Energy Company, LLC, the licensee1, provided a response to Generic Letter (GL) 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems (ADAMS Accession No. ML072910759) for Three Mile Island Nuclear Station, Unit 1 (TMI-1).

Additional information is required for the U.S. Nuclear Regulatory Commission (NRC) staff to determine that the licensee has acceptably demonstrated that the subject systems are in compliance with the current licensing and design bases and applicable regulatory requirements, and that suitable design, operational, and testing control measures are in place for maintaining this compliance as stated in GL 2008-01.

Background:

Guidance on NRC staff expectations is provided by NRC letter dated May 28, 2009, (ADAMS Accession No. ML091390637). These expectations are generally consistent with Nuclear Energy Institute (NEI) guidance provided to the nuclear industry. The NRC staff recommends that the licensee consult NRC letter, dated May 28, 2009, when responding to the following request for additional information:

1. The licensee has stated that TMI [Three Mile Island] is currently performing initial fill ultrasonic testing [UT] checks, post-maintenance fill UT checks, and periodic UT checks for the HPI [high pressure injection], DH [decay heat removal], and BS [building spray] systems. What is the meaning of periodic?

Are checks the same as surveillances and, if not, what is the difference? Are these checks to be continued until technical specification (TS) changes are addressed in response to industry resolution of the gas accumulation TS issues is obtained via the technical specifications task force (TSTF) effort that is underway in response to GL 2008-01?

1 The operating license for TMI-1 has been transferred from AmerGen Energy Company, LLC to Exelon Generation Company, LLC as of January 8, 2009.

2. Provide the following information, for TMI-1:

a. A broad identification of surveillance locations and methods with identification and justification of excluded locations.

b. A description of void volume determination methods.

c. A brief description of the process for re-performance of UT / venting at locations where gas may accumulate during venting at other locations to: (1) verify gas was removed after venting; and, (2) to ensure gas was not transported into a high point that was previously found to be gas-free.

3. The response, for TMI-1, does not identify how gas movement is assessed with respect to operating conditions. The GL requests information for systems required to support all operating modes and all accident conditions. Please provide a response that addresses all the considerations implicit in the GL request.

4. Summarize the corrective action program (CAP) aspects and/or procedures that address vortex formation for the decay heat removal (DHR) pumps during suction from the RCS hot legs, for TMI-1.

5. Summarize the post-surveillance activities, such as gas volume trending and procedural checks to periodically identify leakage through check valves that separate the subject systems from higher pressure locations and the response actions in procedures and the CAP if such leakage is identified, for TMI-1. Include in-series check valves that could be exposed to a higher pressure if the first off check valves were to leak.

6. Summarize the measures used to guard against gas intrusion because of inadvertent draining, system realignments, incorrect maintenance procedures, or other evolutions, for TMI-1.

7. Discuss 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 as it relates to preventing gas intrusion into the systems that are the subject of this GL, for TMI-1.

8. Discuss 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, for TMI-1.

9. Provide a table that lists the current incomplete items and the completion schedule for TMI-1.

10. Training was not identified in the GL but is considered by the NRC to be a necessary part of applying procedures and other activities when addressing the issues identified in the GL. Briefly discuss the training aspects of the issues described by this GL at TMI-1.