ANSWER:
A drainfield is used to treat the waste in the water that is released into soil.
Step-by-step explanation:
- The wastewater enters the drainfiled via the underground tanks.
- This drainfield is usually constructed in an unsaturated soil. The wastewater on being discharged onto the porous soil gets filtered.
- In this process, the soil treats, accepts and disperses water. The water then percolates into the soil where it gets treated naturally to remove all harmful coliform bacteria, viruses and nutrients.