INDEPENDENT ENGINEER WARNS ABOUT MORE THAN COFFERDAM

A Report prepared by the Independent Engineer for the Federal Government on the Muskrat Falls project warned Nalcor long ago about the potential for a leaky cofferdam. The same Report stated Nalcor had failed to record important geotechnical notes detailing the presence of a sensitive clay at the North Spur (the natural dam) called “quick clay” – which has the potential to liquefy under certain conditions and to cause landslides. 

The Independent Report is important for reasons other than the defective aspects of a project the public is learning to hate.

One relates to Nalcor’s attempted suppression of the Report.

Another is that the Report contains serious deficiencies even if there is - finally - limited evidence of a “firewall” separating the Independent Engineer from Nalcor – earlier reports having been demonstrably incapacable of invoking criticism.  

Those matters will be visited later. But, immediately, the public should be apprised of the concerns the Independent Engineer has identified.

First, the leaky cofferdam –

A crisis is playing out daily as Nalcor witnesses the effect of its own megaproject inexperience. They watch as the temperature drops, wondering when frazil ice might form and cause damage to the concrete works – as they look to the native protestors for a scapegoat.

A cofferdam is a structure that provides a temporary dry area to permit the permanent works to be built.  

The Upper cofferdam - now the subject of attention - is basically a large, long (450m) embankment structure. The standard construction design called for a “dumped starter dam topped off by a compacted fill embankment dam…that consists of two rock fill groins constructed from the riverbed up to el. 17m (upstream) and el. 14 m (downstream) with a dumped till impervious zone placed in between them.” Though temporary, it must be properly built in order to be impermeable. It seems Nalcor - never able to stay on any schedule - rushed the effort.

Said the Independent Engineer on page 4:

  

NALCOR had failed to allow time for a complete dewatering or proper cleanup and grouting of cracks in the exposed rock foundation where clays and other till are dumped to make the cofferdam an effective barrier to water penetration. 

The leaking water allowed the fine silts to be washed out - and without them a dry structure became an unlikely prospect. The seepage continued. Flooding of the reservoir naturally a build up of water pressure - which accelerated the water volume through the “broke/disturbed rock”. The event forced Nalcor to vacate the work site and to institute the grouting program needed in the first place.

Stan Marshall has confirmed that the ice boom needed to protect some of the installed works will be delayed until 2017, “…unless there’s an extraordinary mild spell, it can’t be done. We simply ran out of time”, he told The Telegram.

In a nutshell, the delay means higher project costs and a later commissioning schedule. Did you happen to hear Stan Marshall say if the contractor is responsible for the extra cost and the additional delay?

Second, the North Spur -
The Independent Engineer advises:

Readers may remember that “very sensitive” or “quick clay” has the capability to liquefy under certain circumstances including seismic activity, blasting, and pile driving, to name a few of the triggering possibilities. Referencing the above assertion, the IE states that “this material liquefied when being placed in the dumps of the trucks and flowed back out…as they proceeded upgrade”. The motion of the truck, likely over a rough road bed, replicated the kind of disturbance that that causes liquefaction in “sensitive” materials. 

The presence of quick clay at the North Spur, long denied by Nalcor's Gilbert Bennett is disturbing enough – given the risk of dam failure to the residents living downstream. But the Independent Engineer is also concerned about Nalcor's failure to properly record fundamentally important data.

The IE reminds Nalcor of a “project meeting…held in the offices of SNC in Montreal on 14 January 2016 to discuss geological features of the North Spur. The meeting included discussion of “…an anomalous feature in the upstream slope" and noted in "November, 2015 occurrence of liquefiable material in the downstream slope described above.”

The IE said “It was noted during the January 2016 Montreal meeting that very little information was being documented or mapped by site staff about geological features.” The Report stated that “It was agreed that geological mapping of surficial geology and soil mechanics related features would be done in the future.”  (underlining added)

Then the Report gets to the point. It states that a review with the IE’s geotechnical specialist and site staff “during the July 2016 site visit (found) Very little geotechnical information concerning items such as water seepage lines, local slumps/structural anomalies or sample locations was recorded". (underlining added)

In addition, the specialist noted: 

"No “as built” geological mapping plots have been done of the downstream slope. The locations of liquefiable material are generally known but they have not been surveyed or plotted on a suitable map. The IE was informed that this information is recorded and that mapping compilations will be done later, however, no factual or surveyed information was shown by the site staff. In view of the critical nature of liquefiable soils in the slope, the IE contends that a much more systematic review of surficial geology is needed. In particular, the presence of major water seepage, location of known liquefiable materials and their relationship to known stratigraphy is crucial. This information could be crucial if there is ever a slope stability incident or other occurrence which requires an external review of previously documented information.” (underline added)

The citation of those lengthy direct quotations are deliberate for three reasons.  First, they are damming in their implications. Second, Nalcor’s secrecy regarding the adequacy of its North Spur remediation scheme has been persistent and systematic. Nalcor will denigrate a world renowned expect in the case of Dr. Stig Bernander, but it won’t subject its work to an independent investigation. Third, Nalcor has long denied the presence of quick clay at the North Spur.

When Nalcor is accused by the IE of having failed to properly log occurrences of quick clay and other critical data which “could be crucial if there is ever a slope stability incident or other occurrence…” – Houston we have a problem.

It is time that the Mayor of Happy Valley-Goose Bay and other local leaders - including native leaders - unless thay are all of the pretend variety - get a lot more serious about problems at the North Spur.

Third, the Powerhouse Formwork failure

The IE observed…

Dry rot on the formwork timbers and shoddy construction work “contributing factors to the incident”! Readers might want to review a July 2015 post entitled “Engineers Break Silence on Problems at Muskrat Falls” in which engineers working at the site made a number of recommendations to get the project back on track, including one about Quality Assurance. They suggested:

As enlightening as the IE is with respect to the causes of the incident, the Report is slim pickings in terms of detail. The engineers who helped write the July 2015 blog post ask again: where is Nalcor’s capability to run a megaproject? Q&A experts want to know if the various engineers required to sign-off on the formwork’s readiness for the concrete pour actually did so? Did Nalcor ever modify its “Quality Assurance” program?

Fourth, the Transmission Line

The following excerpt is from page 11 of the IE’s Report

This problem was described in a Piece on this blog written by J.P. Schell, P.Eng.(Retired). The article was entitled Design Engineer Baffled by Extent of Muskrat TL Flaw Reported by CBC. Once again, the popped wire represents a colossal failure of quality control processes. The problem occurred in the factory – hundreds of kilometers were spun as the extra or “popped” wire went unnoticed. The faulty wire was shipped here and unloaded – evidently without inspection. So, the defect went unnoticed. 

Then to compound the gap in its quality control procedure, hundreds of kilometers of the wire were strung onto the transmission towers. 

Now the cable must be taken down, purchased again, and re-strung. There is no evidence any party, except Nalcor, is paying for the materials and the cost of the extra work of re-stringing the lines.

That is one dimension of Nalcor's failure regarding the transmission lines. But there are others. 

The IE states that, at the contractor’s insistence, the service roads will be upgraded to an all season standard. Nalcor had planned to provide a grade suitable only for “winter access” in many areas. The change represents a quite significant additional cost considering the circuitous routing required to maintain acceptable gradient for a roadbed stretching over an 1100 km. 

Remember, there is also the cost of hundreds of towers that have to be removed and replaced due to an unsuitable design given the challenging (boggy) terrain. 

Don't you think the public should be looking for a new project cost estimate... and soon? On what basis can Nalcor make the claim they have gone too far to stop? Yes, they have gone too far with projects costs but they are no where near project completion!

Does anyone not think the public should know – from independent sources – the continuing saga of management problems at Muskrat and why this project is fast accelerating towards a cost figure of $15 billion?

In truth, the Independent Engineer’s Report is not nearly as detailed or as comprehensive as it should be. Yet, it is the case that this IE Report is different in tone and content from the ones previously made public. 

The contrast might even cause one to think that the purchase by Stantec Inc., in May of this year, of the WMH Global Inc. - the company with the long-term contract and the role of Independent Engineer for the federal government and the bondholders - is the reason for this more critical content. Perhaps this is why rumours abound that Stantec has been relieved of this contract - a matter to which we await confirmation.

Still, the EI's Report, in its entirety, presents a lower than acceptable standard for review of a mega construction project. We will discuss this problem in a future post. 

Still major deficiences - some reported long ago on this blog - have finally earned the IE's notice.

In addition - and a future post will prove  - if Nalcor had found a way to bury David Vardy's ATIPPA request for this latest Independent Engineer's Report, the public would know a lot less about the issues described here. 

And that - Stan Marshall - is not acceptable.