MO Rev Stat § 643.650 (2021)
2021 Missouri Revised Statutes|Title XL - Additional Executive Departments|Chapter 643 - Air Conservation|Section 643.650 - Sulfur dioxide, ambient air quality monitoring or modeling network.

Effective - 28 Aug 2015   643.650. Sulfur dioxide, ambient air quality monitoring or modeling network. — 1. Any owner of a coal-fired electric generating source in a National Ambient Air Quality Standards nonattainment area currently designated as of April 1, 2015, shall develop an ambient air quality monitoring or modeling network to characterize the sulfur dioxide air quality surrounding the electric generating source. The network shall adequately monitor the ambient air quality for sulfur dioxide surrounding the entire electric generating source and shall operate for not less than twelve consecutive quarters. The owner of such electric generating source shall notify the department of the manner in which it intends to characterize by either modeling or monitoring the air quality around such source. The location of any monitoring network installed by the owner of such electric generating source within a one-hour sulfur dioxide National Ambient Air Quality Standards nonattainment area shall be approved by the department.  2. Affected sources located in undesignated areas that elect to use monitoring to evaluate ambient air quality shall be consulted by the department on the use of existing monitors as well as the location of any new monitors intended to comprise the sulfur dioxide monitoring network. The department shall not submit its recommendation to the Environmental Protection Agency on the manner in which data will be gathered for the designation process that is inconsistent with the elections made by affected sources under this section. Where affected sources have elected to monitor under this section, the department shall submit recommendations for the designation process by the date set by a final, effective, and applicable Environmental Protection Agency requirement relating to state attainment designations and not prior.  3. The department shall consider all ambient air quality monitoring network data collected under subsection 1 of this section and under any agreement authorized under this subsection prior to proposing to the commission any sulfur dioxide limitation, emission reduction requirement, or other requirement for purposes of the one-hour sulfur dioxide National Ambient Air Quality Standard for any electric generating source that has elected to install a monitoring network under this section, except:  (1) The department may propose to the commission any sulfur dioxide limitations or emission reduction requirements specifically agreed to in any voluntary agreement entered into between the department and any owner of an electric generating source that has elected to install a monitoring network under this section; and  (2) The department may propose to the commission any adjustments to the sulfur dioxide limitations or emission reduction requirements applicable to any electric generating source located in a sulfur dioxide nonattainment area and subject to an agreement under subdivision (1) of this subsection, as justified by an ambient air quality analysis relying on no fewer than two quarters of monitored data collected through the monitoring network allowable under subsection 1 of this section and consistent with such agreement.  4. Nothing in this section shall prohibit the department from entering into an agreement with an owner of an electric generating source to limit or reduce sulfur dioxide emissions at such affected source that is below the source's permitted sulfur dioxide emission rate. ­­-------- (L. 2015 H.B. 92 merged with S.B. 445)