SEATTLE – Bertha is on the move again.

The tunnel boring machine began mining again Monday after a brief hiatus when Bertha veered off course.

Bertha stopped drilling February 28 after surveying data showed the machine was about six inches off the tunnel alignment.

Seattle Tunnel Partners designers made minor adjustments to the tunnel alignment between Bertha’s current location and the end of the tunnel, and crews were able to get Bertha back on track.

Map of Bertha's progress as of 3/6/2017 (WSDOT)

As of Monday, Bertha has 960 feet to go after having traveled 8,310 feet from SODO en route to South Lake Union.

Drilling is scheduled to be completed in May.