That depends on what you have:
Cleanout – cannot be used for pumping
Cleanouts are about 4″ across (usually with a twist off cap) that are installed on the line between the house and the tank.
They are for cleaning the line – they do not provide direct access to the tank. We do sometimes use them to help locate the tank. Sometimes they can be used to pump septage out of the line between the house and the tank, but since you can’t directly access the tank and the inlet line is at the top of the tank you *cannot* pump out the tank through a cleanout.
“Pump Port” – can be used for pumping, but is not best practice
Pump ports were very popular for a period of time (before Access Risers) for tanks that were deep. They are a pipe, usually about 8″ across with a cap that are stuck straight through the tank lid or top.
These can be pumped through, but if the lids are accessible and less than 3ft, we highly recommend pumping from the lids – pump ports have no visibility into the tank, no way to clean the filter, and limit the maneuverability of the hose – meaning the pump is less thorough.
Tank Lids & Access Risers – best practice
Tank lids are usually found on either end of the tank (one above the inlet, one above the outlet). (See this section for information about uncovering tank lids.)
For concrete tanks, they are usually about 22 x 22 inches (though they can be other sizes); for plastic tanks and access risers, they are usually about 18″ across and are green plastic circles.
For access risers, the original lids are removed, the riser is put on over the existing hole, and a lid is put on at the top of the riser so that the lids is (closer to) ground level and easier to access.
For pumping, the lids provide maximum visibility so that we can see what is in the tank and maximum access so we can move the hose around and reach all the areas. This is the best choice if the lids are accessible and less than 3ft deep.