As we move ahead with discussing the various components of an onsite wastewater treatment system, I want to emphasize the importance of a systematic approach of review and evaluation. In the past two articles we discussed the source of the wastewater and the pretreatment septic tank. Now we’ll cover the final treatment and dispersal component of a standard system: the gravity soil treatment area (drainfield). The gravity drainfield is possibly the most critical of all final treatment and dispersal options. With only the assistance of a septic tank for primary treatment, the natural soil bacteria have to do the balance
