On February 5, 2013, EPA proposed a Best Available Retrofit Technology (BART) determination for oxides of nitrogen (NO X) for the Navajo Generating Station (NGS), located on the Navajo Nation, and provided a three-month period to accept public comments that was scheduled to close on May 6, 2013. At the request of interested stakeholders, EPA extended the comment period on two occasions, first on March 19, 2013, and again on July 9, 2013. The comment period was scheduled to close October 4, 2013. Additionally, on June 19, 2013, EPA announced our intention to hold five public hearings to accept written and oral comment on our proposed BART determination for NGS. On July 26, 2013, a group of stakeholders, known as the Technical Work Group (TWG), submitted its recommendation for an additional BART Alternative to EPA for consideration (TWG Alternative). EPA is in the process of evaluating this alternative. Because EPA has not yet announced the schedule for the public hearings, and because EPA is still evaluating the TWG Alternative and may supplement our February 5, 2013 proposal, EPA is extending the comment period an additional three months. EPA intends to hold the public hearings prior to the close of this extended comment period and to announce the schedule shortly.