Problems with the older style 6" access include the availability to inspect the baffles to insure proper cleaning. The 24" diameter riser with concrete cover provides adequate visibility for proper cleanout but requires the ground to be excavated to access the cover.

24" Diameter Riser with concrete lids below surface with 6" cleanouts at grade. This is the ideal situation because it doesn't require disturbing the yard to service the tank, but still allows adequate visibility to inspect baffles and thoroughly clean tank. This access can be installed on almost all tanks.