What is the function of a septic tank's inspection port?

The function of a septic tank's inspection port is primarily for monitoring and maintenance access to the tank. This feature allows licensed professionals to check the tank's levels of solid waste and scum, ensuring it operates efficiently and adheres to regulatory standards. The ability to access the septic tank easily makes it simpler to conduct necessary maintenance tasks, such as monitoring the tank's health, evaluating its overall functionality, and planning for pumping services when required. Proper maintenance through the inspection port can prevent system failures, backups, and costly repairs.

In contrast, the other options do not accurately describe the role of the inspection port. While water drainage is essential for the septic system, the inspection port is not designed for that purpose. The connection to the leach field is facilitated by other components of the septic system rather than the inspection port itself. Additionally, septic systems are not intended for the disposal of toxic waste, which is a separate concern that does not relate to any function of the inspection port.