"Cheaper landfill!!
Adds Research to increase landfill productivity by 50%. De-nerfed cost of landfill is achieved at the third level (20 stone)
First level is unlocked with blue science, and the last level with space science.
The mod also adds infinite research using metallurgic science (from vulcanus)."
Recommended: https://mods.factorio.com/mod/remove-productivity-cap
Please note that, while +150% prod might seem enourmous, it's actually equal to what the cost of landfill used to be.