EPA Regional Haze


The EPA has adopted regulations to address regional haze and visibility impairment in the nation’s parks and wilderness areas. This rule requires states to develop and implement air quality protection plans to reduce pollution that causes visibility impairment. These regulations require certain facilities built between 1962 and 1977 to install Best Available Retrofit Technologies (BART).

Under these regulations, states determine BART-based on six factors including the technology available, the costs of compliance, energy and non-air environmental impacts, existing controls at the source, the remaining useful life of the source and the visibility improvement that can be reasonably expected from controlling the emissions. The federal courts having determined that EPA must afford substantial deference to regulatory decisions, including BART determinations, made by the states pursuant to their authority under the Clean Air Act.

Regional Haze - First Round
Antelope Valley Station and Leland Olds Station, as a Best Available Retrofit Technology (BART) source, were both affected by the Regional Haze Rule in North Dakota to reduce emission at these facilities. Basin Electric has fully implemented all emission controls to be compliant with the North Dakota 2008 SIP (state implementation plan). This included the installation of advanced overfire air and low-NOx burners at Antelope Valley Station and a new wet scrubber and selective non-catalytic reduction at Leland Olds Station

Laramie River Station in Wyoming was also subjected to the first round of the Regional Haze Rule. Basin Electric, the EPA, and the Department of Justice reached a settlement for the BART for all three Laramie River Station units. Per the settlement published in the Federal Register on Dec. 30, 2016, Basin Electric will install and operate selective catalytic reduction on Unit 1 by July 1, 2019, and install and operate selective non-catalytic reduction on Units 2 and 3 by Dec. 31, 2018. 

Regional Haze - Second Round

North Dakota and Wyoming will need to develop their second regional haze plan for the 2018-2028 timeline that achieves the reductions required to meet the Uniform Rate of Progress to natural conditions by 2064. 

With implementation of the 2016 Amendment to the Regional Haze Rule, states would need to develop their Second Implementation Period Compliance Plan and meet the submittal deadline of July 31, 2021. Any facility identified for further emission reductions would then have five years from the Federal Register Publication date of SIP to be installed. The regional haze planning process repeats itself on a 10-year cycle unless regulations change or legal challenges occur that affect the schedule. Basin Electric has begun working on the four factor analysis for Antelope Valley Station and Leland Olds Station at the request of the North Dakota Department of Health.