"Dredging" means removal of earth from the bed of a stream, lake, or pond for the purpose of increasing the depth of surface water or obtaining minerals, construction aggregate, or landfill materials. This definition does not include excavation for mining within a pond created by a mining operation approved under this title or under a local zoning ordinance, or a mining operation in existence before zoning, shorelines, or critical areas permits were required for such operations. (Ord. 2123, § 1 (Att.), 2021.)