Abstract |
Section 303(d) of the federal Clean Water Act (CWA) and the U.S. Environmental Protection Agency's (EPA) implementing regulations direct each state to identify and list waters, known as water quality limited segments (WQLSs), in which current required controls of a specified substance are inadequate to achieve water quality standards. For each WQLS, the State is to either establish a Total Maximum Daily Load (TMDL) of the specified substance that the waterbody can receive without violating water quality standards, or demonstrate that water quality standards are being met. St. Mary's River (basin number 02-14-01-03) was first identified on the 1996 303(d) list submitted to the EPA by MDE as being impaired by nutrients, bacteria and sediments, and listings of biological impacts in non-tidal portions and metals added in 2002. On the draft 2004 303(d) List, specific restricted shellfish harvesting areas were identified. This document proposes to establish Total Maximum Daily Loads (TMDL) of fecal coliform at three sites in St. Mary's River (basin number 02-14-01-03), which drains south to the Lower Potomac River: Locust Grove Cove (RID 4aB); St. Inigoes Creek (RID 4aG) and Carthegena Creek (RID 4aH) are located along the St. Mary's River which is along the northern shoreline of the Lower Potomac River. These restricted shellfish harvesting areas are impaired by levels of bacteria exceeding Maryland's water quality standards for fecal coliform, which has resulted in closure of the areas to shellfish harvesting. Fecal coliform is an indicator organism used in water quality monitoring in shellfish waters to indicate fresh sources of pollution from human waste. When the water quality standard for fecal coliform in shellfish waters is exceeded, waters are closed to shellfish harvesting to protect human health due to the potential risk from consuming raw molluscan shellfish from sewage contaminated waters. The water quality goal of these TMDLs is to reduce high fecal coliform concentrations to levels at which the designated uses for these restricted shellfish harvesting areas will be met. |