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.
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.
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.
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.
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.
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.
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.
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.
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: