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IN SOUTH DAKOTA

Regional Haze Program

South Dakota’s Second Round State Implementation Plan

South Dakota finalized its second round Regional Haze process in May of 2022. DANR presented at its Board of Minerals and Environment hearing in April of 2022, and formally submitted its State Implementation Plan to EPA in May of 2022.

On 9/15/2021, DANR's draft State Implementation Plan was submitted to the Federal Land Managers to begin their 60-day review period. On March 19, 2022, the draft State Implementation was public noticed to begin the required 30-day public comment period. The second State Implementation Plan and Appendices are available for viewing.

South Dakota's First 5 Year Progress Report
DANR is required to report every five years on the progress of its approved Regional Haze Program. DANR’s first progress report was submitted to EPA on January 27, 2016. On March 19, 2018 EPA public noticed its intent to approve DANR’s 5 Year Progress Report. EPA’s comment period for its intent to approve closed April 18, 2018. Click Here to view the full proposal of EPA’s action on the proposed rule. To view South Dakota’s first 5 Year Progress Report Click Here.

South Dakota's Third Round State Implementation Plan
DANR is currently working on its third 2028 Regional Haze State Implementation Plan and will include updates as they are drafted.

What is Regional Haze?
Regional haze is visibility impairment caused by air pollution in the form of small particles scattering or absorbing light. Air pollution that impairs visibility is generated over a wide geographic area stemming from a variety of natural (nonanthropogenic) and manmade (anthropogenic) sources, including major an dminor stationary sources, mobile sources, and area sources. Natural sources can include windblown dust and smoke from wildfires. Manmade sources can include motor vehicles, fuel burning equipment, and manufacturing operations. Some particles are directly emitted into the air, while others are formed when gases emitted into the air form particles as they are carried many miles from the source of the pollutants.

The composition of visibility impairing particulates is very complex. Some particles are emitted directly from nonanthropogenic and anthropogenic sources into the air, while others form as a result of mixing and oxidizing of gases in the atmosphere. In addition, meteorological forces play a strong role in the dynamics of particulate movement, composition, and visibility impacts.

Background on the Clean Air Act Regional Haze Rule
EPA promulgated the regional haze rule on July 1, 1999. EPA’s rule requires states to “establish goals (expressed in deciviews) that provide for reasonable progress towards achieving natural visibility conditions” for each Class I area within a state by 2064. The reasonable progress goals must provide for an improvement in visibility for the most impaired days over the period of the implementation plan and ensure no degradation in visibility for the least impaired days over the same period. South Dakota has two Class I areas within its borders; Badlands National Park and Wind Cave National Park. The Regional Haze Rule requires states to submit a series of State Implementation Plans to protect visibility in each of the 156 Class I areas throughout the country. The federal Regional Haze Rule requires each state to conduct a full update ofits Regional Haze Program every ten years. The first update was originally due in 2018, however on January 20, 2017, EPA finalized revisions to the Regional Haze Rule to streamline, strengthen, and clarify certain aspects of the Regional Haze Program. One of the revisions to the rule was updating the State Implementation Plan submittal deadline for the second planning period from July 31, 2018 to July 31, 2021.