This document, upon approval by the U.S. Environmental Protection Agency (EPA), establishes a Total Maximum Daily Load (TMDL) for mercury (Hg) in the Millington Wildlife Management Area (WMA) Ponds located in the Maryland 8-digit (MD 8-digit) Upper Chester River Watershed (basin number 02130510) (2008 Integrated Report of Surface Water Quality in Maryland Assessment Unit ID: MD-02130510-Millington Wildlife Ponds). Section 303(d) of the federal Clean Water Act (CWA) and the EPA's 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 required to either establish a TMDL of the specified substance that the waterbody can receive without violating water quality standards, or demonstrate that water quality standards are being met (CFR 2010b).