Why is it important to collect wastewater samples at the sampling points before entering an industrial facility for an inspection?

Collecting wastewater samples at the sampling points before entering an industrial facility is crucial for ensuring that the sample represents the wastewater as it is being discharged from the facility. This practice helps to avoid any potential biases that could be introduced by factors occurring within the facility, such as variations in processes, chemical additions, or temporary disruptions. By sampling at the designated points, inspectors can capture a true representation of the effluent, which is key for accurate analysis and compliance with environmental regulations.

This approach is essential for maintaining the integrity of the data collected, as any contamination or alteration of the wastewater due to the introduction of external factors could skew results and lead to incorrect assessments of the facility's operations and its impact on the environment.