The add-on Drill Control is a powerful application that can be used to create horizontal drill designs or import as-built drills from survey data. It uses Alignments, Profile Views and Profiles as base entities for the designs. The data of these designs can be read into Dynamo with the nodes from the Arkance Systems Node Library for Civil 3D Dynamo:
A lot of information can be found and the Civil 3D objects like the Alignment and Profiles can be used in other functions as well.
Project information can be read, and if there is a preview saved, it can be requested also.
Table information from the drawing can be found for further processing.
The data can be read but not changed. Also it is not possible to create new drills from Dynamo. You need the Drill Control software for that.