Which type of soil is best for septic system absorption fields?

Sandy soil is the most suitable option for septic system absorption fields due to its ability to facilitate effective drainage and aeration. Sandy soil has larger particle sizes compared to clay, which promotes better water movement and reduces the likelihood of saturation. This characteristic is crucial for a septic system as it allows effluent to percolate through the soil, where natural filtration processes occur. The larger pores in sandy soil also help maintain adequate oxygen levels, which are essential for the microorganisms that break down waste.

In contrast, clay soil has small particles that can hold water and create a barrier to drainage. This can lead to pooling and inadequate treatment of effluent. Rocky soil can present challenges as well, including difficulty in installation and uneven distribution of effluent. Silt, while better than clay, tends to hold moisture and may not drain as well as sandy soil, potentially leading to similar issues as found with clay. Therefore, sandy soil is the optimal choice for promoting proper absorption and treatment in septic systems.