'Professional incompetence': Muskrat engineer stripped of licence for 2016 collapse

A structural engineer has been disciplined for making "material errors" and miscalculations that contributed to the collapse of a woodenformwork at Muskrat Falls in May 2016 that resulted in a near-miss for a group of workers.

PeterLiuof Ontario has been stripped of his right to practise engineering in Newfoundland and Labrador by the province's association of engineers and geoscientists, a group known as PEGNL.

'Conduct deserving of sanction'

The decision was part of an April 25ruling by an adjudication tribunal, the first in more than two years in this province, and is the latest development for a troubled project that is now at the centre of a long-running public inquiry because of massive cost and schedule overruns.

In an agreed statement of facts, Liu admitted heengaged in "conduct deserving of sanction, professional incompetence and/or conduct unbecoming a professional member or permit holder" under the Engineers and Geoscientists Act.

The discipline relates to a May 29, 2016, incident at the powerhouse in Muskrat Falls in which a portion of the wooden formworkfor a concrete structure called a draft tubecollapsed.

"When there are public structure failures like this it gets our attention and we take it pretty seriously. This led to us investigating the matter and to our disciplinary process being put in place. And you can see the result," said Geoff Emberley, PEGNL's CEO and registrar.

Liu was employed by Astaldi Canada, which was building the powerhouse and spillway for Nalcor Energy.

Part of the project included the construction of four sets of draft tube formworks and related supports, which Astaldi sub-contracted to U.S.-based Contractor's Engineer Inc., or CEI.

During a massive pour of concrete nearly three years ago, the formwork on draft tube No. 2 failed, resulting in five workers falling into the wet concrete mixture, completely submerging one of the workers.

The formwork was designed and fabricated by CEI and installed by Astaldi.

An investigation found that the design of the draft tube elbow formworks was "not based on sound engineering judgment" and there were "inconsistent and incorrect loading calculations."

In reviewing, approving and stamping the design drawings, Liu "failed to identify and take necessary followup action pertaining to theuse of incorrect design criteria by subcontractor CEI, which failed to adhere to the use of Canadian codes and standards," the tribunal found.

Liuwas employed as an assistant project engineer with Astaldi, but was laid off by the company in late 2016. His licence to practise engineering in the province expired in March 2017.

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Astaldiis suing CEI over the incident, with the matter still before the province's supreme court.

An external investigation on behalf of Nalcorfound that "deficiencies in the shoring system" used to support the formworkcontributed to the collapse.

In order to have his licence reinstated in the province, Liu would have to complete various training courses. He was also ordered to pay $5,000 to cover a portion of the hearing costs.

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