If the septic tank is verified water tight, what is the required distance from a sewage tank to a groundwater drain down gradient?

The required distance from a sewage tank to a groundwater drain down gradient is 25 feet when the septic tank is verified to be water-tight. This guideline is based on the need to prevent the potential contamination of groundwater sources from effluent that may seep from a septic system.

A water-tight septic tank is designed to effectively contain sewage and prevent leakage; however, maintaining a minimum distance between the tank and groundwater drains is crucial to safeguard public health and protect the environment. The 25-foot distance allows for adequate separation, ensuring that even in the unlikely event of any failure or malfunction, contaminants do not easily reach the groundwater.

In contrast, other distances specified in the options are either unnecessarily extensive or may not provide the intended level of safety based on regulatory standards, which is why they are not the correct answers. The most accepted and established minimum distance of 25 feet reflects practical experience and aligns with regulatory guidelines to mitigate risks related to groundwater contamination.