The revision is a separate document to the Arizona Regional Haze State Implementation Plan submitted December 2003. The Revision meets specific commitments outlined in the December 2003 SIP (Enclosures 2 through 7) as well as a correction to the authorizing regional haze statutes. The submittal contains a SIP completeness checklist and seven enclosures.

The regional haze rule explicitly recognizes the authority of tribes to implement the provisions of the rule, in accordance with principles of federal Indian law, and as provided by the Clean Air Act and the tribal authority rule. The amount of modification, if any, needed for this report to fulfill tribal needs may vary
considerably from tribe to tribe. The authors have striven to ensure that all references to tribes in the document are consistent with principles of tribal sovereignty and autonomy as reflected in the above framework.

The Arizona State Implementation Plan describes the programs that the State will rely upon to make reasonable progress toward “preventing any future and … remedying any existing impairment of visibility” in the large parks and wilderness areas in Arizona and those in other states that may be affected by pollution generated in Arizona (Class I areas). The federal regional haze rules require states to develop and submit SIPs for improving visibility through the year 2018 that make reasonable progress toward achieving “natural visibility conditions” by the year 2064. This plan is designed to adopt the basic visibility program that addresses impairment of visibility that can be traced to older major industrial sources and implements recommendations adopted by the Grand Canyon Visibility Transport Commission in its 1996 report to EPA.

The Committee selected the following environmental goal: A goal with the purpose of showing continued progress through 2018 by; 1) improving visibility to move days now in the poor/very poor categories up to the fair category, and 2) moving days classified as fair to the good/excellent categories. A progress
assessment will be conducted every 5 years through 2018. The members concluded that this option provides a clear, long term method to track visibility trends in the Phoenix metropolitan area. Additionally, the Committee reached general agreement that the index should not be used to affect short term actions because other programs, such as the High Pollution Advisory Program, are currently in place.

In March 2000, Governor Jane Hull convened the Brown Cloud Summit to examine methods to improve visibility in the Phoenix Metropolitan Area. As part of this Summit, a Visibility Standards Subcommittee was established to recommend methods for measuring visible air quality and tracking improvements in visible air quality over time. Based on its research, the Visibility Standards Subcommittee recommended that a visibility index be established through a public survey process representative of a cross-section of residents. Acting on the recommendation, ADEQ established the Visibility Index Oversight Committee. The Committee’s goal was to coordinate the involvement of Phoenix-area residents in the development of a visibility index.