ML21069A053

From kanterella
Jump to navigation Jump to search

Comment (187) of Jan Boudart on Notice of Intent to Conduct Scoping Process and Prepare Environmental Impact Statement; NextEra Energy Point Beach, LLC, Point Beach Nuclear Plant, Units 1 and 2
ML21069A053
Person / Time
Site: Point Beach  NextEra Energy icon.png
Issue date: 03/03/2021
From: Boudart J
- No Known Affiliation
To:
Office of Administration
References
86FR7747 00187, NRC-2020-0277
Download: ML21069A053 (3)


Text

3/9/2021 blob:https://www.fdms.gov/6e59f6fe-9af2-40aa-9724-7376940a418a SUNI Review Complete Template=ADM-013 As of: 3/9/21 4:05 PM E-RIDS=ADM-03 Received: March 03, 2021 PUBLIC SUBMISSION ADD: Phyllis Clark, Bill Rogers, Kevin Status: Pending_Post Tracking No. klu-e8cf-vksu Folk, Stacey Imboden, Mary Neely Comments Due: March 03, 2021 Comment (187) Submission Type: Web Publication Date:2/1/2021 Docket: NRC-2020-0277 Citation: 86 FR 7747 Notice of Intent to Conduct Scoping Process and Prepare Environmental Impact Statement NextEra Energy Point Beach, LLC; Point Beach Nuclear Plant, Unit Nos. 1 and 2 Comment On: NRC-2020-0277-0001 Notice of Intent To Conduct Scoping Process and Prepare Environmental Impact Statement; NextEra Energy Point Beach, LLC, Point Beach Nuclear Plant, Units 1 and 2 Document: NRC-2020-0277-DRAFT-0192 Comment on FR Doc # 2021-02001 Submitter Information Name: Jan Boudart Address:

Chicago, IL, 60626 Email: janboudart1@gmail.com Phone: 415.301.1129 General Comment Please see attached file on embrittlement of the reactors at Point Beach NPP Attachments 210303JBComments2NRC blob:https://www.fdms.gov/6e59f6fe-9af2-40aa-9724-7376940a418a 1/1

SCOPING COMMENTS REGARDING THE PROPOSED LICENSE EXTENSION FOR THE POINT BEACH NUCLEAR POWER PLANT Re: Docket ID: NRC-2020-0277 Point Beach Nuclear Plant, Units 1 & 2 MARCH 3, 2021 submitted by Jan Boudart Introduction This comment is intended to explain why the added risk of reactor-vessel embrittlement must be part of the EIS. Please include scenarios analyzing how accidents that involve cracking of an embrittled reactor vessel would affect the environment and the community and how they would be handled as Point Beach NPP ages.

Point Beach is two (Units 1 and 2) two-loop pressured water reactors. The pressurized loop is used to keep the core cool and transfer heat to a steam generator. The reactor vessel is subject to extreme heat and neutron bombardment for a minimum of 94% of its lifetime. These two factors, heat and neutron bombardment, change the quality of the pressure vessel material, i.e. stainless steel. The change decreases the flexibility of the material and increases its brittleness. It is thought that such a problem can be mitigated by placing the pressure vessel into the conditions present at the manufacture of the stainless-steel alloy (annealing). But such a process would be very expensive and the increase in flexibility of the material might not be certain enough for the utility to countenance such an expense.

To my knowledge annealing has not been tried in the U.S.

The danger in a brittle reactor vessel is that it might crack or break in stressful situations like earthquakes or floods. If it did break, it couldnt contain water and temperatures in the fuel rods could increase to the melting point of the fuel and its cladding. As the fuel melts and supporting material breaks down, critical mass of the fuel could generate a nuclear explosion.

But short of the nuclear explosions scenario, a breakdown in the fuel rods, could expose the zircalloy cladding to the extreme temperature where zirconium snatches oxygen out of gaseous water molecules, releasing the hydrogen to form a gas having a powerful expansive force. Such a force could suddenly overcome the strength of both the pressure vessel and the containment structure resulting in Fukushima-like explosions that lifted radionuclides into the air and scattered them in dangerous fallout.

This is why embrittlement of the pressure vessel is recognized as a menace. Allowing the pressure vessel to become embrittled is playing Russian Roulette with a beyond-design, unforeseeable natural phenomenon like an earthquake, a derecho, unexpectedly high water in Lake Michigan, or a loss of water in the primary loop from an undetectable leaky or broken pipe.

Point Beach specifics Point beach reactor vessels have become embrittled. But presumably the NRC requires their embrittlement to be monitored by removing coupons from the body of the reactor vessel and subjecting these samples to a Charpy test YouTube.com/watch?v=tpGhqQvftAo\ to see if they can tolerate design-basis accidents. However, if the example of Palisades, a one-reactor unit, is any example, such monitoring is wishful thinking. All data from one of the coupon tests has been lost, misplaced or it never existed. After a much-too-long interval a coupon was to be tested in 2019, but the NRC exempted that test because Palisades is scheduled for shut-down in 2022.

But the Japanese, as they began to re-instate their nuclear fleet after the Fukushima episode, have physically tested at least one reactor, the Genkai 1, and found it too brittle to consider starting up as it approached 40 years of operation (commissioned 1975).

The example of Genkai 1 is definitely a cautionary tale. Computer models of embrittlement made a prediction that did not square with the reality of the physical test. In figure 1, the physical tests are shown with red Xs, and the computer model is the solid line (that allows for the margin of error). After 1

V 100

~

i->

- J ma in f rro

~100 a:,

c:, X D Q) re, ,.._,

ti\

~ 50 E

Q)

- so "' "' - X

.8 V'I C

.9l

  • 0 io ears o ope

-~

..0 0 ( I dept of ae le QJ

~ - 16 0 c:,

0 1 2 3 5 6 7 flu (10 19n/cm ]

almost 40 years of operation Genkai 1 was above the 70-year level of the curve. Embrittlement did not conform to the algorithms on which predictions were based.

Even if the NRC required Point Beach to perform ASME testing on coupons placed in the reactor vessel, there would not be enough of them to continue the monitoring through to 60 years of reactor life.

Therefore, the EIS must treat the problem of reactor embrittlement including the environmental effect of shutting down Point Beach instead of letting its embrittlement menace be exacerbated by continuing its operation up to 60 or 80 years.

2