Which term stands for the allowable pollutant load distributed among sources within a watershed?

• A. Total Maximum Daily Load
• B. Water Quality Based Effluent Limitation
• C. Waste Load Allocation
• D. Groundwater Allowance

Answer: (C)

In the TMDL framework, the total amount of pollutant a waterbody can receive without violating water quality standards is capped and then divided among sources in the watershed. The portion assigned to point sources—dischargers like treatment plants and industrial facilities—is called the Waste Load Allocation. The rest of the load is allocated to nonpoint sources and natural background as Load Allocations, with an added Margin of Safety to cover uncertainties. Groundwater Allowance isn’t part of this standard allocation scheme, and Water Quality Based Effluent Limitations are permit-based limits derived from standards, not the allocation term itself.