Minn. Stat. § 273.1341: TACONITE ASSISTANCE AREA.

A "taconite assistance area" means the geographic area that falls within the boundaries of a school district that contains:

(1) a municipality in which the assessed valuation of unmined iron ore on May 1, 1941, was not less than 40 percent of the assessed valuation of all real property;

(2) a municipality in which on January 1, 1977, or the applicable assessment date, there is a taconite concentrating plant or where taconite is mined or quarried or where there is located an electric generating plant which qualifies as a taconite facility; or

(3) a municipality:

(i) that is located in a county that contains a school district described in clause (1) or (2); and

(ii) where active mining of materials subject to the tax under section 298.015, subdivision 1, is occurring, or where a mine subject to the minimum payment under section 298.015, subdivision 3, is located.