The next phase of the Muskrat Falls inquiry will look at why project costs have nearly doubled since it was first sanctioned, and workers who have insight are being asked for their input.

According to a statement Thursday, the commission of inquiry is asking anyone who worked on the project who believe they have information about why costs have ballooned to $12.7 billion to get in touch.

"We'd like to interview people who worked on the Muskrat Falls generating station, the Labrador–island link, or the Labrador transmission assets," said commission co-counsel Barry Learmonth in the release.

"If you have insight into why this cost so much more than expected, we'd like to hear it."

Hearings on the cost overruns begin Feb. 18.

The first two weeks will be in Happy Valley-Goose Bay. and then the hearings will move to St. John's.

"We are reviewing millions of primary documents, commissioning expert reports, and interviewing most senior managers and political leaders," Kate O'Brien, commission co-counsel, said in the release.

"But people who worked on site may have a different perspective again."

Any workers who wish to contact the commission should do so before Jan. 21, the release read.

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