Georgia Septic Installer Practice Test

What should be spread prior to rain during the construction of a Wisconsin mound system when the area is first tilled?

1. An impermeable layer

2. A layer of sand

3. A layer of soil

4. A layer of mulch

The correct answer is: A layer of sand

Spreading a layer of sand prior to rain during the construction of a Wisconsin mound system is crucial for several reasons related to soil drainage and system performance. The primary function of this sand layer is to enhance the percolation of water through the soil, which is vital in septic system installations. In a mound system, proper drainage is essential to ensure that effluent can flow away from the system and not create pooling or saturation in the surrounding soil. Sand has a coarse texture and larger particle size compared to other soils, which allows water to move quickly through it, reducing the chances of stormwater runoff negatively affecting the mound's performance. Additionally, by spreading sand before rain, you are also helping to prevent soil erosion and compaction that could occur if the rainwater directly impacts tilled soil. This ensures that the mound system retains its intended structure and maintains its efficacy over time. The other options do not serve the same beneficial purpose as sand. An impermeable layer would hinder water flow, a layer of soil may not provide the necessary drainage, and a layer of mulch, although useful for moisture retention in other contexts, might not enhance the percolation needed for successful operation of the mound system. Thus, the use of sand is a strategically