Prev Next


(1) For purposes of this subchapter, the department adopts and incorporates by reference:

(a) 40 CFR part 503, Appendix B – Pathogen Treatment Process (58 FR 9387, Feb. 19, 1993, as amended at 64 FR 42573, Aug. 4, 1999), which is available at http://www.ecfr.gov/ or by contacting U.S. Government Publishing Office, 701 North Capitol Street N.W., Washington, DC or 1 (866) 512-1800.

(2) A person may not construct, expand, or operate a new minor compost facility, animal mortality compost facility, or major compost facility without the applicable license from the department after March 11, 2017. A person operating an existing compost facility must comply with the applicable provisions of ARM 17.50.1701 through 17.50.1718 within twelve months after March 11, 2017.

(3) A compost facility regulated under this subchapter must employ a low permeability work pad designed and constructed to:

(a) prevent ponding of storm water or leachate below compost to ensure ground water protection;

(b) prevent release or discharge of water that has come into contact with compost to surface water or ground water;

(c) direct storm water or leachate to the appropriate collection system; and

(d) accommodate equipment used by the facility without damage or failure.

(4) A licensed compost facility:

(a) shall comply with all local zoning and land-use laws of the terms of a conditional use permit;

(b) may not be located in wetlands or a floodplain;

(c) may only accept appropriate feedstock necessary for the approved license;

(d) shall ensure finished compost contains no more than two percent sharp or angular inorganic objects;

(e) composting biosolids, septage, sewage sludge, or meeting the definition of a major compost facility provided for in ARM 17.50.403, shall comply with the ground water monitoring provisions in ARM Title 17, chapter 50, subchapter 13 and meet the requirements in 40 CFR part 503, Appendix B – Pathogen Treatment Process (58 FR 9387, Feb. 19, 1993, as amended at 64 FR 42573, Aug. 4, 1999); and

(f) shall locate feedstock receiving or storage areas, composting piles or windrows, or curing or finished compost in accordance with Table 1.


                                                            Table 1


            Minimum Horizontal Separation Requirements

            for Compost Facilities


            Separation (feet)


            1. Property line                                                       100

            2. Property line (animal carcass facility)                 300

            3. Residence or place of business                          500

            4. Potable water well or supply                               200

            5. Surface water body                                             200

            6. Drainage swale                                                   150



(5) The owner or operator of a compost facility shall obtain a Montana pollutant discharge elimination system (MPDES) permit from the department before the facility discharges storm water to state surface waters, or disturbs more than one acre of ground during construction or operation.

(6) The owner or operator of a compost facility located at a licensed solid waste management system (SWMS) shall operate according to the department-approved facility and maintenance plan for the SWMS.

(7) Specific analytical methods described in "Test Methods for Evaluating Solid Waste Physical/Chemical Methods" (SW-846) may be required by the department to characterize incoming feedstock if deemed necessary by the department.


History: 75-10-204, MCA; IMP, 75-10-204, MCA; NEW, 2017 MAR p. 285, Eff. 3/11/17.

Home  |   Search  |   About Us  |   Contact Us  |   Help  |   Disclaimer  |   Privacy & Security