I need to replace the existing panel and increase the size of it. This panel is fed by the disconnect that has no grounding (the building was built back in 60's). I'd like to know what I should do with it. The building is located in MD.
Updates:
I'm helping the church to increase the size and # of breakers of a panel. The old panel was 70A and it's replaced as 100A (as shown in the first picture). The panel is fed by an existing disconnect (2nd picture), which is 100A as well. The cable was good for 100A, but its still be replaced because it's deteriorated. While the electrician installing the new cable, they told me that the existing disconnect does not have EGC. Actually, there is no EGC for the entire system. The electrician said a grounding electrode need to be installed, but I wonder if it's necessary since it's existing condition.