Which factor determines how many samples must be collected for utilities monitoring lead and copper for the first time?

The correct factor that determines how many samples must be collected for utilities monitoring lead and copper for the first time is the size of the system. This is because the number of samples required is directly linked to the size of the water distribution system, which is often measured in terms of the number of service connections or the overall population served.

Utilities are required to collect a specified number of samples based on the total volume of water served and the number of taps or connections in the system. Larger systems serving more people will have a larger sample size requirement to ensure adequate representation of the water quality across the entire distribution network. This approach helps in identifying potential sources of lead and copper contamination, allowing for an effective assessment of the water quality and compliance with regulatory standards.

Population served and service connection age do play essential roles in the overall evaluation of water quality and potential risk factors, but they do not determine the specific number of samples required for monitoring in the same way that system size does. Water quality parameters are crucial for assessing the conditions under which contaminants can leach into the drinking water but do not influence the number of samples to be collected either.