It's been 3 months and still no answers about Muskrat Falls formworks collapse

An official with Nalcor Energy says a clean-up is underway at the site of a serious industrial accident at the Muskrat Falls construction project, and the area has been deemed safefor the resumption ofconstruction activities.

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"Astaldi (has) started work to safely and carefully remove the material from the draft tube that was associated with this incident,"Nalcorspokesperson Karen O'Neill wrote Friday in anemailto CBC News.

But there's still no definitive answersas to why a specialized wooden formwork collapsed on May 29,spilling some 500 cubic metres of wet concrete and rattling workers on the massive and controversial project.

That's the equivalent of about 17 concrete basements for an average sized home.

"The investigation is very comprehensive and is looking at many factors," O'Neill explained.

"The investigation into the root cause is still ongoing and therefore a full analysis has not yet been completed."

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AstaldiCanada, a division of theItalian firm,has the construction contract for the powerhouse and intakes for the Lower Churchill Project atMuskrat Falls in central Labrador.

No serious injuries in incident

The project had been dogged by controversy, most notably cost and schedule overruns, and a dispute between Astaldi and Nalcor over construction costs.

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In June, Nalcor's new chief executive officer, Stan Marshall, agreed it was appropriate to describethe project as a boondoggle.

The investigation into the root cause is still ongoing and therefore a full analysis has not yet been completed.- Karen O'Neill

But new worries arose in late May during construction of draft tube No. 2, one of four large concretepipes that willreturn water to the Churchill River after it runs through the power turbines.

Wooden formworkdesigned and built by a Kansas company, called Contractor's Engineer Inc.,collapsed as concrete was being poured.

There were no serious injuries, but work on that section of the project was suspended.

Nalcordid not say how long the clean-up will take, how the concrete will be removed, or what affect the collapse will have on the project.

It's also unclear how much the collapse will cost, and who is picking up the tab.