2009-10-22_AgendaPacket - Laserfiche WebLink

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Interested Parties Page 2 September 2009 ® A tab with just the new listing to the 2010 draft TMDL List -this is a subset of the first bullet. ® A tab with all new impairments -these include the new listings to the TMDL list (see the bullet just above) plus new impairment listings for which a TMDL is not required. An example would be an additional to Appendix A of the already approved Mercury TMDL (see Section [2] below for more details). ® A tab with removals and corrections from the EPA approved 2008 TMDL List -these are not delistings (see the next bullet below) but all other actions that change the 2010 TMDL List. ® A tab showing delistings between 2008 and 2010 -these are waterbodies that are determined to be meeting water quality standards and are, thus, removed from the inventory. ® A tab showing changes to Appendix A of the EPA approved Mercury TMDL. -see Section 2 below for more details Another document placed on the MPCA TMDL List web site is the Guidance Manual for assessing the quality of Minnesota surface waters for determination of impairment: 305(b) report and 303(d) list. This document describes our state water quality standards, the data collection and quality requirements, and assessment tools used when developing the 303(d) TMDL List. There are still some potential changes to this initial draft through the recommendations of the Agency natural background study group, the MPCA delisting study group, and from data analyses of PFOS in fish tissue that are presently on-going. If significant changes occur from these groups or as a result of comments received during the 30-day public comment period, you will be informed by letter and, depending on the specifics, through a notice in the State Register before the draft TMDL List is submitted to EPA for their review and approval. 2. The revisions to A~wendix A of the Ayeproved Statewide Mercurv TMDDL The MPCA Mercury TMDL is comprised of the reduction goal for mercury deposition in the main body of the report and two appendices. Appendix A contains the list of lakes and river segments covered by the P/lercury TMDL and Appendix B contains the list of NPDES permittees covered by the mercury TMDL. The TMDL was originally approved on March 27, 2007, and revisions to Appendix A were approved on Apri13, 2008. The 2008 Mercury TMDL Appendix A totaled 998 water bodies. Subsequently, three AUIDs were split, resulting in a total of 1001 water bodies. An additiona195 waterbodies are being added in the 2010 cycle, resulting in a grand total of 1096 water bodies in the 2010 revision to Appendix A of the EPA-approved Mercury TMDL. The water bodies in Appendix A have fish tissue concentrations greater than 0.2 mg/kg and equal to or less than 0.572 mg/kg. Greater concentrations result in inclusion in the TMDL List. 2