Septic Tank Facts Note that in the process of floating to the top of the tank, some of the smaller solid particles, oils and greases are forced, by the outflow of water, into the outlet baffle leading into the drainfield or dry well. Over time, the build up of these small solid particles, oils, greases, fats ect...can eventually cause the failure of your system. What can be done? Bio-Remediation The drainfield typically does a good job of allowing the affluent to slowly and naturally filter into the ground, sand and gravel leach bed. This process leaves behind solids, oils, greases and primarily soap scum along with undigested food. This is why the modern septic system needs some extra help along the way. BioRemediation is no "silver bullet" for a failed or seriously failing system, however; the proper application of a scientifically proven BioRemediation product will help insure a very happy septic system and owner.