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Friday 25 September 2015

DAN CRUMMELL: THE PEOPLE OF MUD LAKE AWAIT YOUR ANSWER.

Guest Post written by Cabot Martin
My letter of September 11, 2015 to Minister Dan Crummell, on the perils of a North Spur collapse to workers both on the Spur and at the powerhouse site across the river, to downstream residents and to provincial finances alike has, so far, gone unanswered. Perhaps, that is not surprising. Despite the urgent nature of the matter, in the past he has usually taken about a month to reply.
One point not fully covered in my letter concerns the technical analysis on which Nalcor has based its “There’s no problem with the North Spur“ position. Seemingly, it has been adopted without critical analysis by Mr. Crummell.
This conclusion was driven home by an article in last Weekend's Telegram (September 18, 2015) reprinted from Happy Valley – Goose Bay’s “The Labradorian”.   That’s the paper that dismissed award winning journalist Michael Johansen back in November 2013 when he dared question Muskrat’s fundamentals.
Given that we are all finally getting our minds around the depth of Nalcor’s incompetence and their unceasing PR campaign to cover up all things Muskrat in particular, The Telegram’s decision to reprint an article in which Nalcor V-P, Gill Bennett, takes off in full and fanciful flight on the lack of risk at the North Spur makes it timely, yea necessary-  to explore the issue of Nalcor’s much ballyhooed ”Third Party” reviews.

I should say that “fast and loose” is common place when it comes to the North Spur – in every way.

The Telegram’s North Spur article, referred to above, includes a photo of the powerhouse construction site on the south side of the river. It calls the ultra solid rock feature , known as Spirit Mountain, on the far right of the photo “The North Spur”.

Sorry, Telegram…you got it wrong. Spirit Mountain is to the North Spur as granite is to runny cheese. (Photo not shown in The Telegram's digital version.)

Rather, the downstream side of the North Spur is properly pictured below.

Now, you can really see what it looks like – a real pile of unstable garbage – enough to make any construction type bivver.









                           The downstream side of the North Spur, September, 2015.

I hasten to add that Mr Bennett’s “Third Party Review” supposedly offsets, refutes, dismisses, overrides, make a nullity, assigns to the dustbin of irrelevancy  the opinions of two of the world’s most respected Hydro/Quick Clay experts – James L. Gordon of Montreal and Dr Stig Bernander of Sweden – the opinions of whom on the North Spur readers of Uncle Gnarley are no doubt familiar.
Now Gil Bennett’s PR banter can be taken for what it is –  the defense by an embattled, incompetent corporate bureaucracy of a weak position on a weak Spur.  
 Rather, it is the Minister’s position I want to examine.
In the second last paragraph of the Minister’s letter to me dated August 26th, 2015 he stated that – “The engineering design for the North Spur stabilization works has been reviewed by three different independent third parties, who have advised that the design is adequate”.
I can find no corroboration for this statement. I presume that the three parties are – Retired Professor Izzat Idriss from California (a seismic expert), Dr. Leroueil from Laval University, and another whom I am unable to identify.
I have been advised on excellent  authority that Professor Idriss did not produce a report, and only participated in some discussions.
Dr. Leroueil, for his part, produced one letter in English, just over one page long, and another letter in French. Both are available on Nalcor's website having been first posted by local blogger, Tom Baird, in a piece entitled "On the North Spur". The English version of the second letter is reproduced below, which is an independent, professional translation of the letter in French.
Dr. Leroueil is very careful in his comments.
In the English letter, dated August 24, 2014, he clearly states that -
·     “my knowledge on the dynamic behaviour of soils and its analysis is rather limited”. One would expect that a reviewer of a liquefiable soil would require expertise in dynamic behaviour.

·     “Moreover, I received the main report but not the appendices”. This indicates that the review was not based on all relevant data.

·     “Section 2 is satisfactory to me”…”Stabilization works increase the factor of safety from about 1.0 to 1.6 which is very significant”. Here Dr. Lerouil has commented on the conclusions, and has not mentioned that the detailed calculations, nor whether soil parameters used in the calculations were reviewed. The soil parameters determine the magnitude of the liquefaction risk, and are therefore of primary importance.

·     Dr. Leroueil states that some information is missing in the report, namely –
I think it would be good to give factors of safety for the sections 4 and 90 for the static conditions”.
“more information is needed on the locations of piezocones”
“what is the NKT value considered?”.
“I have been frustrated not to find important figures that are in the appendices”

As stated previously, this indicates the review was based on incomplete data.

· The sections on dynamic analysis is “interesting”… Not an unequivocal endorsement of the design.

·     In minor comments, Dr. Leroueil states: “I have been surprised to read that “the granular material can be very sensitive to their saturation” This is true but I am not sure that this aspect has been considered in the analysis”. This needs to be reviewed further, as soil parameters dictate safety.

-         The letter, in French , dated 26 October 2014 is more theoretical, wherein Dr. Leroueil describes the work of Dr. Bernander as “very basic” (not professional?) and states “to begin [Bernander type] calculations is to begin with many constraints and questions.”

-      He also mistakenly states  “ .. that to my knowledge, Bernander’s method” has only been used for the analysis of existing ruptures, for which the results were already known.”

Nothing could be farther from the truth.  

Dr Bernander’s methodology has been used to explain slides in Sweden that, until then, remained a complete mystery; his analysis was confirmed by a special commission of Inquiry.

Dr. Bernander is both a respected academic and the former Chief Design Engineer for Skanska the largest construction company in Sweden with many, many years of practical experience, something Professor Leroueil cannot claim. 

The rest of the letter is a dissertation on how a failure occurs and what should be done to improve safety.

Amazingly, far from concluding by saying  Bernander is out to lunch, Leroueil concedes that  “The disruption can also come from above, for example through pile-driving, as in the case of Surte researched by Bernander.“

Hence, it is not difficult to identify the source of Minister Crummell’s empty paradoxical brag in his August 26, 2015 letter that Nalcor is going avoid “human activities such as pile driving that could induce landslides.”

And by saying “The disruption can come from above” Leroueil is, in reality, endorsing Dr Bernander’s “Downhill Progressive Landslide” approach, something that Nalcor has told the Independent Engineer not to look at, as there is no evidence of such slides in the whole Lower Churchill Valley- the same Lower Churchill Valley where Dr Bernander on a personal site visit saw all sorts of evidence of a high potential for Downhill Progressive Landslides.

Crummell doesn’t even know on whose analysis he is acting --- and who his real friends are. And if he thinks he can sell the idea that all those excavators and Mack trucks now working on the North Spur, all the digging into Quick Clay for its “removal” are not as dangerous, and as landslide-inducing, as a pile driver, then he has more nerve than is good for any of us.

Lacking any information on the third reviewer, and from the foregoing, it can be concluded that, while in one sense Dr. Leroueil has “reviewed” Nalcor’s North Spur dam safety work, the review is not based on all relevant information, is incomplete, superficial (less than 3 pages) and certainly does not equal an unqualified approval of the design.
So, if Professor Leroueil’s less than expert or considered musings attached are not the “Third Party Reviews” that provide the foundations of Nalcor’s “What me worry?’ position, where are they?
And, if they do exist, why have they not already been made public?
And when will they?
The people of Mud Lake await your answer Mr Crummell.
______________________________________________
The following letter is a French to English Translation of a letter dated October 26, 2014 to   Dr. Regis Bouchard from Serge Leroueil on the issue of North Spur stability found on the Nalcor web site:

Hello Régis,
I haven’t forgotten you, but I was leaving for two weeks of work with Luciano Picarelli in Naples, and my life was complicated by the fact that my luggage (and my computer power supply) arrived three days late (no mistake, the problem was in Toronto!).
Regarding the North Spur, here is my opinion:
-          There is no established methodology for evaluating stability against a downhill progressive failure. Bernander has suggested a very basic methodology that, to my knowledge, has only been used for the analysis of existing ruptures, for which the results were already known. Ariane Locat has adapted the same method for “uphill progressive failures”, which has been used to understand two spreads in the sensitive clays. In my opinion, to begin calculations is to begin with many constraints and questions.

-          From another perspective, the analytical methods consist of defining the initial shear stress along the length of a potential rupture surface, probably mainly horizontal and passing at the base of a slope in our case. This shear stress is at its maximum at approximately the crest of the slope. If a disruption increases the shear stress in one spot up to the soil’s shear resistance, then a progressive rupture can start, and eventually continue until a global rupture occurs. There are two important points in what I have said:

1.)    The initial shear stress. If you show that you have improved the stability of the slope (higher F]), this means that you have diminished your initial shear stresses and that you move further from the soil strength (resistance).
2.)    Disruption that can locally increase the initial shear stress. This disruption can come from above or below. In Québec, the disruption is most often erosion or a small rupture at the foot of the slope. However, as you have protected the foot of your slope, you have removed the possibility of disruption at the foot of the slope. The disruption can also come from above, for example through pile-driving, as in the case of Surte researched by Bernander. And there, it has to be demonstrated that you have taken all the precautions to prevent any disruption at the foot of the slope.
If you improve your stability, therefore diminishing the risk of progressive rupture with regards to what it had been, and if you prevent any disruptions, you cannot have a progressive rupture. I believe this is the way to approach the problem.


Best regards, Serge

_________________________________________________________

Note: the french version of Serge Leroueil's letter dated October 26, 2104 is found on this Link.