During pumping, maintain stable vacuum, prevent tank wall damage, break up heavy solids with agitation

https://mill-wiki.win/index.php/Coming_From_Blockages_to_Clear_Lines:_How_Hydro-Jetting_Enhances_Septic_Tank_Maintenance

During pumping, maintain consistent vacuum, avoid tank wall damage, separate heavy solids with agitation, and never ever go into the tank; lethal gases require stringent confined-space safety procedures.