Virginia Wastewater Class 4 Exam 2025 – 400 Free Practice Questions to Pass the Test

The correct response in this situation is to raise the water level. When a stabilization pond begins to go "septic," it typically indicates that there is a lack of adequate oxygen levels, leading to anaerobic conditions. Raising the water level can help manage this situation by promoting better mixing and potentially enhancing the pond's aeration indirectly by increasing the surface area for gas exchange. It also may dilute the concentration of the organic material present, which can alleviate some of the conditions that contribute to septic conditions.

The other choices, while they might seem plausible, do not address the underlying problem effectively. Increasing aeration could help in some cases but may not be feasible or effective if the pond is already experiencing extreme anaerobic conditions. Adding chemical coagulants might provide short-term benefits for controlling suspended solids but would not tackle the fundamental issue of low oxygen levels in the pond. Reducing inflow to the pond could inadvertently exacerbate the conditions by limiting the water movement and further harming the biological processes within the pond. Each of these alternative actions lacks the direct positive influence on improving conditions in a nearly septic stabilization pond that raising the water level provides.