A Type 1 sanitation system is designed to permit which of the following?

A Type 1 sanitation system is specifically designed to treat human waste to a level that allows for discharge overboard. This type of system typically uses advanced treatment processes, which may include a combination of biological and mechanical methods to break down waste and disinfect the effluent to meet specific regulatory standards before it is released.

Discharging treated waste overboard helps manage sanitation in marine environments, ensuring compliance with environmental regulations and minimizing the impact on the waterway. In contrast, untreated discharge, reliance solely on holding tanks without treatment, or even holding treated waste without discharge would not align with the capabilities and purpose of a Type 1 system. Therefore, the option indicating treatment followed by discharge reflects the system's design and operational intent accurately.