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Re: "Watchdog group questions safety of nuclear plant"
Norm Cohen's post on this matter suggests that NRC is ignoring the
recommendations of the ACRS. While he graciously offers to provide
documentation of the Lochbaum-Cohen views on the matter, he somehow
failed to direct us (and, apparently, the reporter) to documentation of
NRC or ACRS positions. The most recent communication on the matter from
ACRS to NRC, obtained from the NRC website and reproduced below, appears
to be grossly inconsistent with Norm's interpretation of the ACRS
position.
Based on the news account, this public meeting seems fairly typical.
NRC reps presented themselves as targets and Norm and Co. took pot-shots
from all angles. I admire NRC's interest in public involvement. But I
sure would like to see a competent assessment of the effectiveness of
its attempts.
ACRS letter to NRC:
June 14, 2001
The Honorable Richard A. Meserve
Chairman
U.S. Nuclear Regulatory Commission
Washington, D. C. 20555-0001
SUBJECT:
RESPONSE TO YOUR MAY 7, 2001 MEMORANDUM REGARDING DIFFERING
PROFESSIONAL OPINION ON STEAM GENERATOR TUBE ISSUES
Dear Chairman Meserve:
This report responds to the May 7, 2001 memorandum in which you
requested our views on whether immediate actions are
needed, other than those already taken by the staff, to deal with steam
generator tube issues. In February 2001, we submitted
to the Executive Director for Operations (EDO) NUREG-1740 on a differing
professional opinion (DPO) concerning
alternative repair criteria for steam generator tubes. In that report,
we concluded that alternative repair criteria were needed.
The alternative repair criteria and the condition monitoring program for
steam generator tubes that the staff has endorsed can
provide adequate protection of the public health and safety.
We did make recommendations to the EDO directed particularly at
improving the technical bases of the alternative repair
criteria and the reliability of the condition monitoring program. The
more important of these recommendations are:
Evaluate the potential for progression of damage to steam generator
tubes during rapid depressurization caused by a
main steamline rupture.
Monitor performance to search for systematic deviations from the
linear bound on the nonlinear processes of crack
initiation and growth through steam generator tube walls.
Improve the database for the correlation of leakage with voltage
for 7/8" tubes.
Improve the analysis and understanding of radioiodine behavior
during design basis accidents.
Develop a better understanding of the behavior of degraded steam
generator tubes under severe accident conditions.
We did not identify issues that demanded immediate, pre-emptory
resolution for the alternative repair criteria and the condition
monitoring program to continue. We felt that the recommended activities
could be done within the context of the existing Action
Plan on Steam Generators. Research needed to act upon the
recommendations could be prioritized and pursued within the
context of the current research program. We did encourage the staff to
determine promptly whether the effects of forces
associated with depressurization during a main steamline break
constitute a generic safety issue and, if so, to resolve this issue
expeditiously.
We find the approach the EDO has taken so far in response to our
recommendations to be appropriate. We look forward to
reviewing the details of the staff's responses to our recommendations.
Dr. William J. Shack did not participate in the Committee's
deliberations regarding this matter.
Sincerely,
/RA/
George E. Apostolakis
Chairman
References:
1.Memorandum dated May 7, 2001, from Richard A. Meserve, NRC
Chairman, to George Apostolakis, ACRS
Chairman, Subject: Differing Professional Opinion on Steam
Generator Tube Issues.
2.U. S. Nuclear Regulatory Commission, Advisory Committee on Reactor
Safeguards, NUREG-1740, "Voltage-Based
Alternative Repair Criteria," February 2001.
3.U. S. Nuclear Regulatory Commission, Office of Nuclear Reactor
Regulation, Action Plan on Steam Generators.
---------------
Norm Cohen posted:
Date: Thu, 23 Aug 2001 22:04:13 -0400
From: Norman Cohen <ncohen12@HOME.COM>
Subject: Re: "Watchdog group questions safety of nuclear plant"
Hi Sandy, and Radsafers,
Delurking for a moment:
Perhaps it was the way the reporter expressed himself. The "panel"
was the 10 or
more NRC officials at the NRC public meeting on the safety of Salem's
(mostly Unit 2)
steam generators. NRC granted this public meeting in response to a
request from the
UNPLUG Salem Campaign, and sent their senior faciliator, Chip Cameron
plus a whole
posse of NRC officials, to the meeting.
The admission is directly from the NRC's own ACRS (Committee on
Reactor
Safeguards) report which verified the Hopenfeld DPO (Differing
Professional Opinion),
which makes it clear that the NRC "hasn't a clue" (my words) as whether
or not a single
tube rupture may or may not lead to a multiple tube rupture. Dr
Hopenfeld, a senior NRC
inspector, had spent 10 long years trying to get the NRC to listen.
After Indian Point
2 blew a steam generator tube, NRC had to listen.
Anyone who wants Lochbaum's handout or the text from the Praire Island
Coalition's
video, both of which detail how and why multiple tube ruptures could
occur, please
email me at mailto:ncohen12@home.com and I'll be glad to snail mail the
info to you.
Thanks,
Norm
(back to lurkdom)
Sandy Perle wrote:
> There have been many SG tube ruptures. I wonder why the NRC officials
> supposedly said the following. "A panel of Nuclear Regulatory
> Commission officials admitted that they don't know whether a single
> broken steam tube in a Salem nuclear generator could lead to multiple
> beaks and ultimately a core meltdown." Is anyone familiar with what
> was actually said, and who were these 10 NRC officials?
> ---------------------------
>
> "Watchdog group questions safety of nuclear plant"
> Jack Kaskey
>
> "Unplug Salem's concerns ceneter on cracking of alloy tubes
> in generators inside Salem Unit 2. The tubes are bearly identical to
> one that burst 18 months ago at a New York plant".
>
> PENNSVILLE TOWNSHIP- A panel of Nuclear Regulartory Commission
> officials admitted tht they don;t know whether a single broken steam
> tube in a Salem nuclear generator could lead to multiple beaks and
> ultimately a core meltdown. About 10 NRC officials gathered Thursday
> night at the Hampton Inn here from headquarters in Maryland, the
> region office in King of Prussia and the nuclear plants in Salem
> County to address concerns raised by Unplug Salem, a Linwood-based
> group. The group's concerns center on corrosion and cracking of 1300
> alloy tubes contained in four generators inside the containment
> vessel of Salem Unit 2. The generator tubes are nearly identical to
> one that burst 18 months ago at a plant in Indian Point, N.Y.,
> leaking radioactive steam into the atmosphere. NRC officeials said
> nuclear plants are designed to safely shut themselves down when such
> a leak occurs. "The plant is designed to acccomodate the failure of a
> tube," said Glenn Meyer, NRC branch chief for the Salem plants.
> Thursday's meeting, however, focused on a new NRC committee report on
> steam generators that raises the question of whether a single rupture
> could cause a chain reaction of broken tubes. In the event of "gross
> failure' of multiple steam generator tubes, more water could escape
> through steam vents than the plant is designed to replace, said Dave
> Lochbaum, a nuclear safety engineer with the Union of Concerned
> Scientists in Washington, DC. Without sufficient water, the nuclear
> reactor would melt down, Lochbaum said. Such a meltdown would pollute
> much of southern New Jersey with radiation. Meyer said such a
> scenario is only a hypothesis that NRC staff members are evaluating.
> "That's not to say it absolutely can't happen," Meyer said. "Multiple
> tube failures:Can they happen? We can't definetly say 'no'. That's
> what we are pursuing." In the meantime, there is no safety risk with
> continued operation of the nuclear plant, said Rick Ennis, the NRC
> project manager in charge of responding to the steam-generator
> report. NRC officials said a single tube failure is unlikely, because
> plant operator Public Service Electric and Gas plugs tubes when they
> are corroded 40 percent of the way through. The pencil-thin tubes are
> tested for cracks using radio waves. Although current testing methods
> don't typically discover a tube that is only 40% cracked, tubes in a
> high-pressure generator can withstand a crack 85 percent of the way
> through, said Joseph Muscara, an NRC senior metallurigical engineer.
> To date, 871 tubes have been plugged at Salem Unit 2. Meyer said PSEG
> has a strong financial incentive to make sure they plug any tubes
> during refueling outages. If a tube breaks when the plant is
> operating, power production has to stop for weeks, he said.
> Generators in Indian Point Unit 2 and Salem Unit 2 both use the same
> size and type of nickel-alloy tubing. But NRC officials have told
> Unplug Salem coordinator Norm Cohen that a direct comparison between
> the two generators is inappropriate because the Salem tubes have been
> heat-treated. On Thursday, Cohen asked the NRC panel to rpovide
> certification of the heat treatment. But the nuclear officials said
> only PSEG has that information. Cohen and Lochbaum questioned whether
> it was worth the risk to keep the plant running while the NRC
> resolves the question of tube failures in older nuclear steam
> generators.
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