Which of the following is NOT a typical requirement for a percolation test?

The correct answer highlights that measuring water clarity is not a standard requirement for conducting a percolation test. In a percolation test, the primary focus is on evaluating the soil's ability to absorb water, which is essential for determining the suitability of a site for a septic system.

Typical requirements for a percolation test include ensuring that the holes are dug to the appropriate depth to assess the soil layers effectively and allowing for sufficient pre-soak time, which helps to saturate the soil prior to measurement. This pre-soaking is critical as it allows for a more accurate assessment of how the soil will behave when subjected to wastewater. Additionally, the recommendation of using gravel at the bottom of the test holes often helps with drainage during the initial soaking phase.

Measuring water clarity does not relate to the soil’s absorption capacity and is not necessary for evaluating percolation rates. Instead, the test concentrates on the rate at which water drains through the soil, which is determined by observing the water level drop over time rather than its clarity.