For a perc test, what is the first step after filling the hole to a depth of 12 inches?

In a perc test, the first step after filling the hole to a depth of 12 inches is to maintain the water for 15 minutes. This step is crucial because it allows the soil to stabilize and saturate properly. When water is added to the hole, the soil absorbs moisture, and this process takes a little time to equilibrate. Keeping the water in the hole for that duration ensures that the soil pores are adequately filled, which is important for accurately measuring how quickly the soil can absorb water afterward. This initial soaking can significantly impact the accuracy of the percolation rate that will be determined in subsequent steps of the test.