Removing a kick off cement plug to gain access to the well below the plug

Discussion Forum > Well Integrity > Removing a kick off cement plug to gain access to the well below the plug

Removing a kick off cement plug to gain access to the well below the plug

We are working on a well located in a field which is targeted for CO2 storage. One of the wells had a sidetrack drilled several years ago but the original hole was not abandoned according to the standards at the time with the result that the original hole provides a leak path from the proposed CO2 reservoir to overlying porous formations.

The sidetrack leg of the well has now been plugged and abandoned to the required standards and both the 13-3/8” casing and the 9-5/8” casing have been recovered below the kick off cement plug.

This provides access to the kick off plug from surface. But with the cement much harder than the surrounding formation and the 17-1/2” sidetrack hole open gaining access to the original wellbore is considered a challenge.

Question is it be possible to drill out a cement kick off plug with a length of +/- 60 m and regain access to the original wellbore. The top of the 13-3/8” casing is right below the cement plug. The top of the 9-5/8” casing in the original hole is 300 m deeper.

We have searched for papers, there are hundreds of papers on how to set and drill a kick off plug, but no papers addressing how do drill out a cement plug and gain access to the original wellbore

If anyone has experience or ideas on how a kick off plug can be drilled out and removed. I see a similar question from Neil Bergstrom back in 2021 but there were no answers.