### U.S. EPA FACT SHEET

Supplemental Proposal Best Available Retrofit Technology (BART) for Navajo Generating Station, Navajo Nation

September 25 , 2013

Summary of Action
In today’s Supplemental Proposal, EPA is proposing an additional A lternative to BART submitted o n July 26, 2013 by a group of stakeholders , known as the Technical Work Group (TWG). The TWG Alternative would establish a lifetime cap in NO x emissions over 2009

- 2044 that would ensure cumulative NO x emissions from NGS are be low that level . EPA has independently evaluated the TWG Alternative and is proposing to determine that the TWG Alternative is “better than BART” because maintaining emissions below the 2009

- 2044 NO x C ap achieves greater reasonable progress than BART toward s the national visibility goal. EPA is currently taking comment on this alternative as well as the proposed BART and “better than BART” alternative contained in our February 2013 proposal.

Background On Today’s Proposal

 EPA is proposing to reduce harmful nitrogen oxide ( NO x ) emissions from the Navajo Generating Station (NGS), one of the largest sources of NO x emissions in the country. These pollutants contribute to visibility impairment in 11 national parks and wilderness areas surrounding NGS, including the Grand Canyon which is less than 20 miles away from the plant. See map.

 On February 5, 2013, EPA proposed a Best Available Retrofit Technology (BART) determination for NGS, an Alternative to BART, and a framework for evaluating Alternatives to BART tha t provide greater flexibility in the timeframe for compliance in exchange for greater emission reductions

. EPA invited stakeholders to suggest additional Alternatives to BART that meet our proposed framework . The July 26, 2013 TWG A lternative was submitted to meet this framework.

 The TWG is composed of Salt River Project, the U.S. Department of the Interior, the Navajo Nation, the Gila River Indian Community, Environmental Defense Fund, Western Resources Advocates, and the Central Arizona Water Conservation District.

 EPA is accepting comment concurrently on today’s Supplemental Proposal and our proposal from February 5, 2013. The public comment period will close on January 6, 2014

. Emissions Reductions : Over the lifetime of the facility (2009

- 2044) the TWG A lternative will result in greater NO x emission reductions than our proposed BART determination. EPA’s proposed BART determination would reduce emissions by over 84 percent, or a total of 28,500 tons per year.

 Visibility Improvements:
These emission reductions will result in perceptible visibility improvement (greater than 1 deciview) at all eleven Class I areas impacted by NGS.

 Timeframe and Credit for Prior Reductions :

EPA is exercising our discretion under the Tribal Authority Rule (TAR) to allow additional time for NGS to reduce emissions and to give credit for prior reductions. Sources located on tribal land are not subject to the same legal deadlines as sources on state land. The credit for the prior NO x reductions, achieved over 2009

- 2011, is a key component of EPA’s proposed framework for Alternative s to BART.

General Background

 NGS is located on the Navajo Nation Indian Reservation near Page, Arizona and is one of the largest sources of NO x in the country. NGS is a 2,250 MW coal

- fired power plant.

 NO x not only impairs visibility by increasing haze, but also emits pollutants that affect public health. EPA’s proposed action gives NGS several options that will all substantially improve air quality and visibility.

 Under the Clean Air Act, Congress required that EPA improve visibility in 156 federal national parks and wilderness areas across the country. States are required to adopt Regional Haze plans that improve visibility over time. These plans include BART determinat ions, where older sources are evaluated for additional pollution controls. Most states have completed this process and many have required stationary sources under their jurisdiction to install new air pollution controls for BART

. The Navajo Nation has not developed a Tribal Implementation Plan for BART. Therefore, EPA is developing a Federal Implementation Plan for Navajo Generating Station.

 NGS has already installed pollution control equipment to significantly reduce emissions o f sulfur dioxide (SO 2 ) and particulate matter in order to protect visibility and improve air quality. Now EPA is proposing that the facility take comparable action to reduce NO x emissions, the last component of pollution that significantly affects regional haze. In 2011 alone, 4 million people visited the Grand Canyon. Visibility is important to healthy tourism and the economic vitality of the states, local and tribal communities in the West.

 NGS is co

- owned by the U.S. Bureau of Reclamation (24.3%), Salt River Project (21.7%), Los Angeles DWP (21.2%), Arizona Public Service (14%), Nevada Power (11.3%) and Tucson Electric Power (7.5%).

 Los Angeles DWP and Nevada Power have stated their intentions to pull out of NGS. Together they own 32.5 % of the plant, or almost a third of the facility, or almost one unit of the 3

- unit facility.

Next Steps

 EPA is extending the close of the public comment period to January 6, 2014.

 EPA will be hold ing five open house and public hearing events at locations throughout A rizona on November 12

- 15, 2013, as follows:

Date Time Location
November 12 Tuesday Morning 10AM

– 1PM

Concurrent Open House/Hearing LeChee Chapter House, On Coppermine Road, 3 miles south of Page, in LeChee, Arizona
November 12 Tuesday Evening Open House: 3PM

– 5PM

Public Hearing: 6PM

– 9PM Page High School Cultural Arts Building, 434 Lake Powell Blvd., Page, Arizona

November 13 Wednesday Open House: 3PM

– 5PM

Public Hearing: 6PM

– 9PM Hopi Day School, Quarter

- mile East Main Street, Kykotsmovi, Arizona

November 14 Thursday Open House: 3PM

– 5PM

Public Hearing: 6PM

– 10PM Phoenix Convention Center, 100 North 3 rd Street, Phoenix, Arizona

November 15 Friday Open House: 3PM

– 5PM

Public Hearing: 6PM

– 9PM Proscenium Theatre, Pima Community College West Campus, Center for the Arts Building, 2 miles west of I

- 10 on St. Mary’s Road, Tucson, Arizona

For more information, see: http://www.epa.gov/region9/air/navajo/