38 M.R.S. § 592-A

1. Total suspended particulate matter. No person may discharge total suspended particulate matter to the ambient air in an amount or concentration that soils property or creates a nuisance condition. Total suspended particulate matter concentrations of less than 150 micrograms per cubic meter for any 24-hour period in the ambient air are presumed not to constitute soiling or nuisance conditions. Any person who demonstrates on the basis of total suspended particulate ambient air quality monitoring information acceptable to the commissioner that emissions discharged by that person have not substantially caused or contributed to total suspended particulate matter concentrations in excess of 150 micrograms per cubic meter over a 24-hour period at any applicable location may not be held in violation of this subsection. [PL 1989, c. 155, §2 (NEW); PL 1989, c. 890, Pt. A, §40 (AFF); PL 1989, c. 890, Pt. B, §167 (AMD).]

2. Fugitive emissions. Any commercial and industrial source or facility, all municipalities and all state or federal facilities, whether or not requiring a license pursuant to this chapter, that cause or contribute to the discharge of fugitive emissions that the commissioner determines to constitute a nuisance are required to establish and maintain a continuing program for best management practices for suppression of fugitive emissions during any periods of construction, renovation or normal operation. The commissioner shall determine those procedures which constitute best management practices. A description of a source's program for suppression of fugitive emissions must be made available to the commissioner upon request. Public or private roads that are not part of a commercial and industrial source or facility are not subject to the requirements of this subsection. [PL 1991, c. 138 (AMD).]