Conductive soil would shield against EMP, to a degree.
Really?
I just moved to sand country from an area with clay soils. We had a lightening storm and it fried our phone line, which, like the electric lines here, are buried. It was the phone company tech who told me they were really busy due to the storm and the area can have outages from strikes 100 miles away, due to the sandy soil.
Was he wrong?