Dumping - Top Level Dirt

During filling of land in water, I like to make the last (topmost) level all dirt. doing this manually requires 2 Mine Control Towers, and constant management. could that be an option?

maybe somewhere in the what can be dumped menu you can select what layers certain things can be dumped on or the mining tower also

Agree, this is too micromanagy yet is vital for farms. Or at least farms should be able to add soil on their own.