Montana Title 75. Environmental Protection § 75-2-203. Department to set emission levels

(1) The department may establish the limitations of the levels, concentrations, or quantities of emissions of various pollutants from any source necessary to prevent, abate, or control air pollution. Except as otherwise provided in or pursuant to this section, those levels, concentrations, or quantities are controlling, and no emission in excess of those levels is lawful.

(2) In any area where the concentration of air pollution sources or of population or where the nature of the economy or of land and its uses may require, the department may fix more stringent requirements governing the emission of air pollutants than those in effect pursuant to subsection (1).

(3) The department may by rule use any widely recognized measuring system for measuring emission of air contaminants.

(4) Should federal minimum standards of air pollution be set by federal law, the department may, if necessary in some localities of this state, set more stringent standards by rule.