A plan on how to fix the tunnel-boring machine named “Bertha” is expected by the end of the month.

Seattle Tunnel Partners (STP) informed the Washington State Department of Transportation on Friday that it expect to receive a plan on potential repairs from the machine’s manufacturer Hitachi Zosen by the end of this month.

The plan is expected to include a schedule for how long the repair work would take.

Earlier this week, STP told WSDOT that the plan may be completed by the end of the week, but said Friday that more time is needed for the Hitachi to prepare it.

WSDOT officials say it appears likely that repairs will be made by digging a shaft from the surface so the machine can be entered from the front. Entering the back of the machine would require removal of more equipment and likely take longer.

STP will begin work next week on the design of the shaft so if that option is selected, some of the necessary work will already be underway.