ASME, flaw detection, flaws, inspection frequency, leaking nuclear power plants, leaking nuclear power stations, Leaking Nuclear Reactors, leaks, LOCA, loss of coolant accident, mind games, non-destructive testing, NRC, nuclear energy, nuclear power, piping, radioactive leaks, standards, testing, US Budget, USNRC, ways to cut the US budget, weak standards, welds, welfare to work
If anyone needs anymore evidence that the bureaucrats at the US NRC are either stark raving mad or have sub-zero IQs this is it: they are considering how much operational leakage is acceptable at nuclear power stations. Here they apparently do NOT mean the planned legal emissions which poison the environment on a routine basis but rather how much unplanned piping and similar leakage is “acceptable”.
Unless you are young with a brand new everything and are lucky not to have gotten a defective item among your brand-new everything, you know that no leakage is acceptable. This is all the more true for radioactive leakages at nuclear power stations.
There is a reason that some US plumbers make almost as much as President Obama for work weeks of about the same length – leaks are not acceptable. Thus they are well-paid and always working. There is a reason that executives of piping companies are constantly flying around – leaks are not acceptable in any industry except, apparently, the nuclear industry.
Shouldn’t an industry which deals with lethal radioactive materials be held to a higher standard rather than to a lower standard? It should. But, NRC actions show that it thinks the nuclear industry is “special” and should have constant exemptions and be held to lower standards than everyone else.
The NRC is also trying to drag the foremost standards association through the mud by making misleading statements, along with trying to implicate ASME in NRC crimes by mixing and matching pieces and parts of old and new ASME standards. (See more at yesterday’s post).
First round of comments follows. If you missed it, don’t worry, there will be other chances. Meanwhile, petition your elected officials to shut down the NRC to help balance the US budget and save Americans from cancer – also costly to the budget.
“Incorporation of American Society of Mechanical Engineers Codes and New and Revised ASME Code Cases Docket ID: NRC-2011-0088
Agency: Nuclear Regulatory Commission (NRC) “Summary
The U.S. Nuclear Regulatory Commission (NRC) is proposing to amend its regulations to incorporate by reference seven recent editions and addenda to the American Society of Mechanical Engineers (ASME) codes for nuclear power plants and a standard for quality assurance. The NRC is also proposing to incorporate by reference four ASME code cases. This action is in accordance with the NRC’s policy to periodically update the regulations to incorporate by reference new editions and addenda of the ASME codes and is intended to maintain the safety of nuclear power plants and to make NRC activities more effective and efficient.” http://www.regulations.gov/#!docketDetail;D=NRC-2011-0088 (Comment deadline Wednesday, 2 December 11.59 pm ET)
Here are some excerpts from this docket:
“The NRC proposes to revise § 50.55a(a)(1)(ii) to clarify that Section XI Non-mandatory Appendix U of the 2013 Edition of ASME BPV Code Section XI is not incorporated by reference and therefore not approved for use. The NRC is developing an integrated approach to the issue of operational leakage. The NRC has not completed its determination of how Appendix U fits into this integrated approach to address the operational leakage issue at nuclear power plants. The operational leakage issue has many factors that need to be considered such as acceptance criteria, corrective actions, application of repair/replacement requirements, component operability determination, concerns related to continued operation, maximum acceptable leakage rates, flaw growth rates, flaw measurement techniques, schedules for eliminating leakage, and when or if the leakage requires authorization by the NRC. The NRC plans to complete the development of the regulatory approach to operational leakage and issue it in a future rulemaking.
Then in schizophrenic mode the NRC points out that leakage is bad because it causes corrosion (which could lead to nuclear disaster as at Davis Besse):
“Leakage from a partial penetration weld into the annulus between the nozzle and head material can cause corrosion of the low alloy steel head. While initially limited in leak rate, due to limited surface area of the weld being in contact with the annulus region, corrosion of the vessel head material can expose more of the weld surface to the annulus, allowing a greater leak rate
The application of ASME BPV Code Case N-729-1 was necessary because the inspections required by the 2004 Edition of the ASME BPV Code, Section XI were not written to address degradation of the RPV upper head penetration nozzles welds by primary water stress corrosion cracking (PWSCC). The safety consequences of inadequate inspections can be significant. The NRC’s determination that the ASME Code required inspections are inadequate is based upon operating experience and analysis. The absence of an effective inspection regime could, over time, result in unacceptable circumferential cracking, or the degradation of the RPV upper head or other reactor coolant system components by leakage assisted corrosion. These degradation mechanisms increase the probability of a loss-of-coolant accident.
Only a surface examination of the wetted surface of the partial penetration weld can reliably detect flaws in the weld. Unfortunately, this examination cannot size the flaws in the weld, and, if performed manually, requires significant radiological dose to examine all the partial penetration welds on the upper head.”
How does NRC jump from supposed inability to size the flaws to inability to detect a flaw before leakage? Furthermore, a high resolution ultrasonic inspection with a good technician should be able to size flaws, as they are able to for the needed reactor pressure vessel inspections which the NRC refuses to do or have done.
NRC contradicts itself: “As such, the available techniques are only able to detect a flaw after it has caused leakage. These techniques are a bare metal visual examination or a volumetric leak path assessment performed on the frequency of the volumetric examination.
Volumetric leak path examinations are only done on outages when a volumetric examination of the nozzle is performed… The NRC proposes to increase the frequency of the bare metal visual examinations of “cold heads” to identify potential leakage as soon as reasonably possible because of the volumetric examination limitations.” [But, NRC allows decrease in frequency!] “Therefore, the NRC proposes to condition Note 4 of ASME BPV Code Case N-729-4 to require a bare metal visual exam each outage in which a volumetric exam is not performed.” Well, they should do volumetric exams (presumably they mean ultrasonic testing but they may mean thickness measurement and/or leak volume) at all outages! Easier and better – shut these old reactors down!
Wait…this is actually decreasing inspection because fuel outage is 18 to 24 mths (1 1/2 to 2 yrs) and they are changing it to 5 years or 60 mths! How is decreasing frequency increasing it?
“The NRC also proposes to allow “cold head” plants to extend their bare metal visual inspection frequency from once each refueling outage, as stated in Table 1 of N-729-1, to once every 5 years, but only if the licensee performed a wetted surface examination of all of the partial penetration welds during the previous volumetric examination. Applying the conditioned bare metal visual inspection frequency or a volumetric examination each outage will allow licensees to identify any potential leakage through the partial penetration welds prior to significant degradation of the low alloy steel head material, thereby providing reasonable assurance of the structural integrity of the reactor coolant pressure boundary.” Huh? They just changed it from each outage (once every 1 1/2 to 2 years) to once every 5 years and then they discuss how doing it at each outage will increase safety?
Why is volumetric exam not available? The utilities don’t want to pay for it?
“These issues, including the operational experience, the fact that volumetric examination is not available to interrogate the partial penetration welds, and potential regulatory options, were discussed publicly at multiple ASME Code meetings, at the annual Materials Program Technical Information Exchange public meeting held at the NRC Headquarters in June 2013, and at the 2013 NRC Regulatory Information Conference.
10 CFR 50.55a(g)(6)(ii)(D)(4) Surface Exam Acceptance Criteria
The NRC proposes to adopt a new condition (to be included in proposed § 50.55a(g)(6)(ii)(D)(4)) to define surface examination acceptance criteria. Paragraph -3132(b) of ASME BPV Code Case N-729-4 sets forth the acceptance criteria for surface examinations. In general, throughout Section XI of the ASME BPV Code, the acceptance criteria for surface examinations default to Section III, Paragraph NB-5352, “Acceptance Standards”. Typically, for rounded indications, the indication was only unacceptable if it was greater than 3/16 inch in size“.
While neither flaws nor leaking flaws are acceptable, how does NRC jump from flaw size to flaw plus leak? “The NRC requested that the code case authors include a requirement that any size rounded indication causing nozzle leakage is unacceptable due to operating experience identifying PWSCC under rounded indications less than 3/16inch in size.” Well, duh… a leak is a leak!
“Recently, the ASME Code Committee approved an interpretation of the language in Paragraph -3132(b) that implied any size rounded indication is acceptable unless there is relevant indication of nozzle leakage, even those greater than 3/16inch. The NRC does not agree with the interpretation and maintains its original stance on rounded indications that any size rounded indication is unacceptable if there is an indication of leakage.” Did you see that? ASME says a flaw is ok UNLESS there is leakage and the NRC says no flaw is ok if there is leakage! What weird mind games the NRC is playing! “Since the adoption of ASME BPV Code Case N-729-1 into § 50.55a(g)(6)(ii)(D), all licensees have used the NRC’s stance in implementing Paragraph -3132(b), even after the recent ASME Code Committee interpretation approval over NRC objection.” And, so, why are they pontificating leakage still? Or nozzle leakage isn’t ok but other leaks are being pontificated?
Well there you have it or rather some it it! Their contorted “reasoning” may have driven them mad and they hope to drag us all with them, while giving us all cancer too!
The NRC must be shut down for public safety’s sake, and to help balance the US budget. They can then go on welfare to work to clean-up the Savannah River Nuclear site or other nuclear sites.
Some related links: