No equipment, material, or property is exempt from the payment of ad valorem tax by reason of the payment of the gross production tax as herein provided except such equipment, machinery, tools, material, or property as is actually necessary and being used at the site of a producing well in the production of oil or gas; and it is expressly declared that no ice plants, hospitals, office buildings, garages, residences, gasoline extraction or absorption plants, water systems, fuel systems, roominghouses, and other buildings, nor any equipment or material used in connection therewith is exempt from ad valorem tax, nor are drilling rigs exempt. The real property is not exempt under this chapter except to the extent of the mineral interests therein.