Wisconsin Mound Soil Absorption System and Area FillPractice Exam

In a Wisconsin mound, what ratio of mound slope is typically accepted?

1. 1 to 1

2. 3 to 1

3. 4 to 1

4. 2 to 1

The correct answer is: 3 to 1

In the context of Wisconsin mound systems, a slope ratio of 3 to 1 is typically accepted. This means that for every three units of horizontal distance, there is one unit of vertical rise. This slope ratio is considered ideal for ensuring proper drainage and preventing erosion of the mound structure. A 3 to 1 slope allows for adequate surface water runoff while maintaining the integrity of the mound, preventing it from becoming too steep, which can lead to instability. This gentle slope facilitates the absorption of effluent into the surrounding soil without overwhelming the system, promoting effective treatment of wastewater. Using a slope that is too steep, such as those indicated by other options, can increase the risk of soil erosion, which can lead to the failure of the mound system. Conversely, slopes that are too shallow may not provide adequate drainage, resulting in water pooling on the surface and potentially causing system inefficiencies. Therefore, the 3 to 1 slope ratio is a balanced approach that meets engineering and environmental considerations for mound construction and efficiency.