From which part of a surface application system are samples for testing typically collected?

The correct answer focuses on the pump tank effluent line port as the appropriate location for collecting samples for testing in a surface application system. The effluent from the pump tank is the portion of treated wastewater that has gone through the system and is ready for distribution or further processing. Sampling at this point allows for an accurate assessment of the treatment system's performance and the quality of the effluent before it is applied to the surface.

Collecting samples from the pump tank effluent line port ensures that the testing reflects the actual conditions of the treated wastewater as it is released from the treatment unit. This location is critical since it captures the effectiveness of the entire treatment process and provides valuable data regarding compliance with environmental regulations.

Other potential sample collection points, such as the inlet line, treatment unit outlet, or dosing tank, would not provide the same level of insight into the effluent quality as the pump tank effluent line port. The inlet line would contain untreated wastewater, while the treatment unit outlet could provide varying results depending on the specific treatment system dynamics, and the dosing tank is more related to the operational aspects rather than effluent quality. Collecting samples at the pump tank effluent line port, therefore, represents a best practice for accurately testing the system's performance