EPA’s Regional Haze Program requires states to develop and implement air quality protection plans (so-called State Implementation Plans, or “SIPS”) to reduce the pollution that causes visibility impairment in the nations national parks and wilderness areas. (Click here to see a map showing the 156 protected “Class I” visibility areas in the U.S.) A key component of the Regional Haze Rule is the requirement to install and operate the best available retrofit technology (BART) for qualifying older, existing sources of visibility impairing pollutants. Minnesota–and Minnesota’s taconite industry in particular–has had its share of woes recently trying to implement the Regional Haze Rule (see below). So perhaps there is some small measure of comfort knowing that  other states share our BART Blues. North Dakota, for example, whose…