What is a key factor when evaluating the performance of an existing mound system?

Evaluating the performance of an existing mound system largely hinges on the level of effluent treatment efficiency. This factor directly reflects how effectively the system reduces pollutants and pathogens from the wastewater before it returns to the environment. High effluent treatment efficiency indicates that the system is functioning optimally and is capable of protecting groundwater and surface waters from contamination, which is essential for public health and environmental safety.

While initial installation cost, frequency of maintenance, and surrounding land can all influence the overall system performance or its effectiveness, they do not directly measure how well the system treats effluent. Therefore, focusing on treatment efficiency provides the clearest understanding of the system’s operational success and its ability to meet regulatory standards.