The Total Maximum Daily Load (TMDL) program has the potential to affect adversely aggregates mining operations in at least two ways.
The TMDL program is a water-quality based pollution control program designed to maintain designated uses for water bodies throughout each state. A TMDL is a calculation of the maximum amount of a pollutant that a water body can receive and still achieve state or federal water-quality standards. The TMDL identifies the reductions needed to meet water-quality standards. It then allocates these reductions among the sources in the watershed.
The TMDL rule was initiated in section 303 (d) of the 1972 Clean Water Act. Section 303 (d) requires states to identify waters not meeting water-quality standards, set priorities for TMDL development and develop a TMDL for each pollutant for each listed water. Typical pollutants associated with aggregates mining include total suspended solids and total dissolved solids. A single water body may require multiple TMDLs to be developed. Many states are in the process of implementing the federal TMDL program. The EPA approves or disapproves the state’s submissions. If disapproved, EPA will act in lieu of the state.
Updated: September 2012