ML12296A009

2012/10/16 NRR E-mail Capture - Public Comment - Proposed Refueling Plan at Duane Arnold - Action Taken Regarding Your Comment

ML12296A009
Person / Time
Site:	Duane Arnold
Issue date:	10/16/2012
From:	Lochbaum D Union of Concerned Scientists
To:	Feintuch K Division of Operating Reactor Licensing
References
TAC ME8572
Download: ML12296A009 (4)

Text

1NRR-PMDAPEm ResourceFrom:Dave Lochbaum [DLochbaum@ucsusa.org]Sent:Tuesday, October 16, 2012 12:50 PMTo:Feintuch, KarlCc:Frankl, Istvan; Ring, Mark; Haeg, Lucas; Murray, Robert

Subject:

RE: Public Comment - RE: Proposed refueling plan at Duane Arnold - Action taken regarding your comment

Dear Mr. Feintuch:

Sorry for the delay getting back to you.

I have reviewed the safety evaluation report issued by the NRC with the Duane Arnold license amendment, particularly Section 6.0 that you called my attention to. I appreciate the NRC specifically addressing the three questions I posed in my email. I am satisfied by those reponses and appreciate, again, the NRC looking into the issues and taking the time and effort to address them.

Thanks, Dave Lochbaum UCS From: Feintuch, Karl [Karl.Feintuch@nrc.gov] Sent: Thursday, September 27, 2012 5:59 PM To: Dave Lochbaum Cc: Frankl, Istvan; Ring, Mark; Haeg, Lucas; Murray, Robert

Subject:

Public Comment - RE: Proposed refueling plan at Duane Arnold - Action taken regarding your comment

Dear Mr. Lochbaum:

The purpose of this message is to provide you with the results of our processing of your email message to me dated Friday, August 10, 2012 9:11 AM. Your message (reproduced below) was entered into ADAMS as ML12226A165. For convenience a courtesy copy of ML12226A165 is attached. You raised concerns about a licensing action whose evaluation was in process. To give it full consideration on its technical merit, your message was provided to the cognizant technical Reviewers, who responded in detail to your numbered concerns (items 1), 2), and 3) in your message below). The technical responses to your numbered concerns, along with the full text of your message below, were inserted into the draft Safety Evaluation being prepared by NRC staff. Your comments and the Reviewer responses contributed to the weight of evidence applied by NRC staff in arriving at its decision regarding the request by NextEra Energy Duane Arnold, LLC (the licensee for Duane Arnold Energy Center). Today, September 27, 2012, the NRC issued License Amendment No. 283 to the Renewed Facility Operating License for Duane Arnold Energy Center. The associated ADAMS Accession Number for the issued amendment is ML12249A317. Your message and the NRC staff response are in Section 6.0 of the issued Safety Evaluation contained in our amendment letter. Although the issued amendment is profiled as publically available, there is a short administrative delay caused by the process for releasing documents until the general public is able to access available documents in ADAMS. A courtesy copy of the issued amendment is attached.

2 Thank you for communicating your concerns to me. This message describes in detail how we ensured that your information was brought to the attention of the cognizant NRC staff who participated in the decision on the action about which you commented. Sincerely, Karl D. Feintuch Project Manager United States Nuclear Regulatory Commission NRR/DORL/LPL3-1 301-415-3079 Karl.Feintuch@nrc.gov From: Dave Lochbaum [1] Sent: Friday, August 10, 2012 9:11 AM To: Feintuch, Karl Cc: Leeds, Eric; Witte, Ulrich; Casto, Chuck

Subject:

Proposed refueling plan at Duane Arnold Hello Mr. Feintuch:

Ulrich Witte, a colleague and friend, brought to my attention the correspondence exchange between the Duane Arnold licensee and the NRC (e.g., ADAMS Accession Nos. ML121000327, ML12179A299, ML12209A420, ML12122A212, and ML12199A130). The licensee wants to apply a protective coating to the inside surface of the torus at Duane Arnold during the upcoming refueling outage 23 (RFO 23). Doing so requires draining water from the torus and preventing water entering the torus during the work activities.

The licensee proposes to rely on one train of the core spray system to satisfy reactor core cooling regulatory requirements during this work. But core spray normally takes suction from the torus and its minimum flow recirculation line returns water to the torus. The licensee proposes to realign this core spray subsystem to take suction from the condensate storage tank and to disable the minimum flow recirculation function.

In reviewing the available materials regarding this proposal, I was unable to find answers to the following questions:

1) Why doesn't the licensee offload the entire reactor core to the spent fuel pool prior to and throughout the torus activities? Doing so would eliminate the need for the core spray subsystem. Has this licensee placed schedule (i.e., shorter refueling outages) ahead of safety?

2) Has the seismic risk from core spray using suction from the condensate storage tank vice the torus been evaluated? I have never worked at Duane Arnold, but I've worked at several boiling water reactors similar in design to it. The condensate storage tank - the normal suction for the high pressure coolant injection and reactor core isolation cooling systems and alternate suction for the core spray and residual heat removal systems - is typically not credited in safety studies because of the challenge in seismically qualifying the condensate storage tank and its associated piping. Here, the licensee proposes to swap the torus - a more seismically robust source -to the condensate storage tank - a more seismically fragile source - without apparently justifying that margin reduction.

33) What about reactor vessel pressurization events during the torus work? The licensee provided incomplete justification for its proposal to eliminate the minimum flow recirculation function for the core spray pump during the proposed torus outage. The licensee's justification argued that reactor vessel pressure is always below the core spray injection valve opening pressure setpoint during Modes 4 and 5, thus providing complete assurance that this valve will open in time to prevent damage to the core spray pump from operation at no or low flow conditions. But that logic is simply not reflected in the BWR/4 Standard Technical Specifications (STS) and their bases issued by the NRC staff in April 2012 (ML12104A192 and ML12104A193). Minimum flow recirculation is required for the core spray pumps in Modes 4 and 5 in the STS. The flaw in the licensee's logic is that a loss of shutdown cooling could cause the reactor vessel pressure to increase above the opening pressure setpoint for the core spray injection valve. Last year's tragedy at Fukushima vividly illustrated the consequences from reactor vessel pressure being higher than the discharge pressure of makeup sources. The proposal by the licensee sets the stage for replicating elements of that disaster: (1) shutdown cooling is lost, (2) the ensuing heatup of the reactor vessel water increases the reactor vessel pressure above the injection valve's opening setpoint, and (3) the solitary core spray pump dead-heads until it is irrevocably damaged.

UCS urges the NRC staff not to approve this amendment request until all applicable questions have been properly answered.

Thanks, David Lochbaum Director, Nuclear Safety Project Union of Concerned Scientists PO Box 15316 Chattanooga, TN 37415 (423) 468-9272 office (423) 488-8318 cell dlochbaum@ucsusa.org Hearing Identifier: NRR_PMDA Email Number: 510 Mail Envelope Properties (7B4F27A2B8788B46892F0DDD79245669B8683D02)

Subject:

RE: Public Comment - RE: Proposed refueling plan at Duane Arnold - Action taken regarding your comment Sent Date: 10/16/2012 12:49:42 PM Received Date: 10/16/2012 12:52:58 PM From: Dave Lochbaum Created By: DLochbaum@ucsusa.org Recipients: "Frankl, Istvan" <Istvan.Frankl@nrc.gov> Tracking Status: None "Ring, Mark" <Mark.Ring@nrc.gov> Tracking Status: None "Haeg, Lucas" <Lucas.Haeg@nrc.gov>

Tracking Status: None "Murray, Robert" <Robert.Murray@nrc.gov> Tracking Status: None "Feintuch, Karl" <Karl.Feintuch@nrc.gov> Tracking Status: None Post Office: UCXSREX054147.ucs.usa Files Size Date & Time MESSAGE 7198 10/16/2012 12:52:58 PM Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date: Recipients Received: