What is the maximum size allowed for a perc hole?

The maximum size allowed for a perc hole is indeed 12 inches. Perc holes, which are used to determine the rate of absorption for soil in the context of septic systems, must adhere to specific standards set by local and state regulations to ensure accurate testing and effective system design.

A 12-inch diameter for a perc hole allows for sufficient area to assess soil characteristics without compromising the integrity of the test. This size facilitates better water infiltration and gives a more reliable measurement of how quickly the soil can absorb water, which is crucial for determining the appropriate design for a septic system. Larger holes can potentially disturb the surrounding soil too much, leading to inaccurate results.

In contrast, using smaller sizes, such as 6, 8, or 10 inches, may not provide a good representation of the soil's filtration capabilities, as they limit the amount of soil available for observation and interaction with the water. Therefore, setting the maximum size at 12 inches is essential for conducting a precise percolation test and designing a septic system that operates effectively and safely.