Which factor does NOT affect the reliability of the soil percolation test?

The reliability of the soil percolation test is most influenced by several factors that directly impact water movement through the soil. The size of the hole, soil condition, and site evaluation all play significant roles in determining the percolation rate and overall effectiveness of the test.

The size of the hole can influence the amount of water that is held in the test area and the flow rate of water through the surrounding soil. Similarly, the condition of the soil, such as its moisture content, compaction, and structure, is critical, as these characteristics directly dictate how water percolates through it. Furthermore, a thorough site evaluation can identify specific local conditions that may affect percolation, like the presence of groundwater or soil layers.

In contrast, the shape of the test hole does not have a significant impact on the test results. As long as the hole is appropriately sized and depth is maintained, whether it is round, square, or otherwise shaped should not influence how water moves through the soil surrounding it. This makes the shape of the test hole a less critical factor in determining the reliability of the soil percolation test.