When the issue venture senses 600 gpm and the return venturi senses 40 gpm or less for 10 seconds, what happens to the lead pump?

When the issue venturi senses a flow of 600 gallons per minute (gpm) and the return venturi detects a significantly lower flow of 40 gpm or less for a duration of 10 seconds, the lead pump continues to operate while the second pump is activated. This scenario typically suggests a discrepancy between the supply and return flow rates, which might indicate a potential problem such as a blockage or other issues in the system.

The decision for the lead pump to keep running while adding a second pump is based on the need to maintain adequate system pressure and flow. By bringing the second pump online, the system aims to address the flow disparity and ensure optimal operation while avoiding a complete shutdown that could disrupt overall system functionality. This helps maintain a continuous supply, balancing the demand and aligning with typical operational protocols where redundancy is crucial for systems involving water and fuel management.

In contrast, the other options do not accurately reflect this operational strategy. Shutting down the lead pump entirely would not effectively manage the flow issue, and simply continuing to run without any corrective action does not address the imbalance between the issue and return flows.