Illinois Real Estate Practice Exam

A percolation test is primarily designed to evaluate the rate at which water is absorbed into the ground, which is critical information when determining the suitability of soil for a septic system or lagoon. During this test, water is introduced into a dug hole and timed to see how quickly the water level drops. The results indicate how well the soil can drain, which can significantly impact the design and permit approval of septic systems, especially in areas where municipal sewer systems are unavailable. This measurement helps ensure that any effluent discharged into the ground can be adequately treated by the soil, promoting environmental safety and preventing contamination. Other options, such as determining the depth of the water table or the quality and temperature of underground water, are not outcomes of a percolation test. Therefore, the focus on the absorption rate makes this answer the most appropriate choice for what a percolation test reveals.