The mast/conduit will typically penetrate the roof and attach to a meter base. Depending on the area, the meter base is usually serviced and maintained by the local electric utility. At the meter base, there may be another conduit that feeds into the electrical service panel located here outside the building. It can be different from one utility to the next but typically they will maintain items one and six of the items depicted on the sketch. The homeowner is normally responsible for everything else. Hire a professional licensed electrician to perform any work on these items.
Key Inspection Points
Inspect for physical integrity. If there is any physical damage noted that would allow water or varmints inside the enclosure, notify your electric utility.