Abstract: A septic tank effluent filter includes a housing positioned external to and downstream a septic tank for receiving the effluent prior to it being released into a drainfield positioned downstream the housing. The housing includes an inlet port and an offset outlet ports on an opposing wall for connection between the septic tank and drainfield. A cylindrical container is carried within the housing and is connected directly to the outlet port for having the effluent flow from within the housing through the uniformly perforated cylindrical wall of the container to outlet port. A circular base plate of the container provides a baffle and prevents the undesirable direct streaming of the effluent from the inlet port to the outlet port. A plastic mesh bag is filled with polystyrene plastic beads having a large surface to volume ratio, thus a large surface area within a desirable space.

Abstract: An apparatus and method for manufacturing a drainage line unit. The apparatus includes a mandrel having an inner cavity. Rear, upper and front openings communicate with the mandrel cavity. Preferably, a controller connected to at least one sensor is operably positioned to control the apparatus. A pipe feeder feeds perforated vent pipe through the inner cavity of the mandrel from the rear opening to the front opening and therethrough. The pipe is positioned within the inner tube cavity so as to define a void space between the pipe and the wall of the mandrel. A hopper assembly has an exit port positioned for feeding a plurality of plastic bodies into the cavity. A blower produces a sufficient air flow through the mandrel cavity for moving the plurality of plastic bodies to substantially fill the void space so that the pipe emerges from the front opening of the mandrel surrounded by the plurality of plastic bodies.