Upper North Branch of the Potomac River in Garrett County, Maryland
Notice of Intent to Establish Iron and Aluminum Total Maximum Daily Load
Section 303(d) of the federal Clean Water Act requires Maryland to: (1) identify waters, known as water quality limited segments (WQLSs), where technology-based effluent limitations and other required controls cannot achieve water quality standards; (2) for each listed water, establish Total Maximum Daily Loads (TMDLs) for pollutants preventing the attainment of water quality standards; and (3) offer an opportunity for public review and comment on the proposed TMDLs.
The Maryland Department of the Environment (MDE) has identified the waters of the Upper North Branch Potomac River, located in Garrett County, as impaired by metals (1996 listing); metals – aluminum, iron, manganese (2008 listings); sediments (1996 listing); nutrients (1996 listing); low pH (1996 listing); and impacts to biological communities (2002/2004 listing). A water quality analysis (WQA) to address the 1996 metals listing was developed by MDE and approved by EPA in 2006. The WQA determined that a TMDL for metals in the entire Upper North Branch Potomac River watershed was not necessary to achieve water quality standards, but impairments were identified in certain tributaries and a portion of the river’s mainstem. This TMDL document addresses the listings for aluminum and iron in the specified areas of the watershed. A TMDL for sediment was approved by EPA in 2007. A TMDL to address the listing for low pH was approved by EPA in 2008. The listings for manganese and impacts to biological communities will be addressed separately at a future date.
The TMDL sets the maximum load limit for the impairing substance. The TMDL also reflects potential load allocations to point sources, nonpoint sources, and a margin of safety that accounts for uncertainty in the procedures used to estimate the TMDLs. Once established by the State, the TMDL will be subject to approval by the United States Environmental Protection Agency (EPA). The established TMDL will support measures needed to attain water quality standards in the Upper North Branch Potomac River watershed.
OPPORTUNITY FOR PUBLIC REVIEW AND COMMENT
A thirty-day public comment period for the draft document will take place from August 13, 2009 through September 11, 2009. A copy of the draft document has been placed in the Ruth Enlow Library of Garrett County, 6 N. Second Street, Oakland, MD 21550 (301-334-3996). The draft document is also available on MDE’s web site at http://www.mde.state.md.us/programs/Water/TMDL , or by contacting Tom Thornton by mail at MDE/SSA, 1800 Washington Boulevard, Suite 540, Baltimore, MD 21230-1718 (410-537-3656; outside the Baltimore area, dial 1-800-633-6101, x3656). Anyone wishing to review the draft documents and supporting information or needing technical information may contact Mr. Thornton during normal business hours.
Written comments concerning the draft document may be submitted to the Department on or before September 11, 2009 and should be sent to Mr. Thornton at the above address or emailed to tthornton@mde.state.md.us. If the Department determines there is sufficient interest, public hearings on the document may be held. All comments received during the comment period will be considered, and the draft document may be revised accordingly prior to its submittal to the U.S. Environmental Protection Agency for approval.
| Draft Total Maximum Daily Loads of Iron and Aluminum for the Upper North Branch Potomac River Watershed, Garrett County, Maryland |
|
Portable Document Format |
| Main Report |
Potomac_TMDL_Fe_Al.pdf (1134KB) |
| Appendix A Water Quality Tables |
Appendix_A .pdf (92KB) |
| Appendix B Hydrology Calibration and Validation Results |
Appendix_B.pdf (235KB) |
| Appendix C West Virginia Upland Load Development |
Appendix_C.pdf (637KB) |
| Appendix D Iron Calibration and Validation Results |
Appendix_D.pdf (302KB) |
| Appendix E Aluminum Calibration and Validation Results |
Appendix_E.pdf (172KB) |
Appendix F Technical Approach Used to Generate Maximum Daily Loads & TMDL Daily Load Plots and Statistics |
Appendix_F.pdf (176KB) |