Georgia Septic Installer Practice Test

What percentage of sand fill in a Wisconsin mound system must not exceed 2mm in diameter?

1. 10%

2. 20%

3. 30%

4. 40%

The correct answer is: 20%

In a Wisconsin mound system, the requirement is that not more than 20% of the sand fill shall consist of particles that are 2 mm in diameter or less. This specification is crucial because the size of the sand particles affects the permeability and overall performance of the mound system. If the sand fill contains too many fine particles, it may lead to poor drainage, increase the risk of anaerobic conditions, and ultimately compromise the effectiveness of the wastewater treatment process. Therefore, the 20% threshold ensures that the sand used possesses appropriate characteristics for optimal system function.