NR 502.12(15)(a)1. 1. Samples of the finished compost that is ready for sale, distribution or use shall be collected every 2,000 tons or 4,000 cubic yards, with a minimum of one sample per year, or, alternatively, in accordance with the testing frequency specified by the United States Composting Council's Seal of Testing Assurance program, unless a different frequency is approved in writing by the department, and tested for the parameters in Tables 1 and 2.
NR 502.12 Note Note: Only class A compost under sub. NR 502.12 (16) is subject to the limits in Tables 1 and 2. “Test Methods for Evaluation of Compost and Composting" (2002) and a list of laboratories certified under the Seal of Testing Assurance program are available from the United States Composting Council, 5400 Grosvernor Lane, Bethesda, Md 20814 (301) 897-2715,
NR 502.12(15)(a)1.a. a. Samples shall be collected, handled and analyzed in accordance with methods listed in “Test Methods for Evaluation of Compost and Composting" published in 2002 by the United States Composting Council or other methods approved in writing by the department. Samples shall be tested at a laboratory certified under the United States Composting Council's Seal of Testing Assurance program or at another laboratory approved in writing by the department.
NR 502.12 Note Note: “Test Methods for Evaluation of Compost and Composting" (2002) and a list of laboratories certified under the Seal of Testing Assurance program are available from the United States Composting Council, 15400 Grosvernor Lane, Bethesda, Md 20814 (301) 897-2715,
NR 502.12(15)(a)1.b. b. Test results shall be made available upon request to the department, potential users of the compost, and to the general public.
NR 502.12(15)(a)2. 2. Unfiltered leachate samples shall be taken from the collection basin or tank, and tested quarterly for the first 4 quarters and annually thereafter for BOD5, COD, field pH, field conductivity corrected to 25°C, nitrate+nitrite-nitrogen, and total dissolved solids.
NR 502.12(15)(a)3. 3. Compost pile turning frequency and temperature readings as appropriate to the composting method used shall be documented and maintained to demonstrate pathogen reduction and odor control activities.
NR 502.12(15)(a)4. 4. The facility shall be visually inspected by the owner or operator quarterly to evaluate storm water discharge quality and performance of discharge controls, and twice per year to identify non-storm water discharges if present.
NR 502.12(15)(b) (b) Unless exempt under sub. (2), (3), (4), or (5), the owner or operator of a composting facility regulated under this section shall prepare and submit an annual report to the department by March 1 on forms supplied by the department. The annual report shall include at least the following information:
NR 502.12(15)(b)1. 1. Name and address of the facility.
NR 502.12(15)(b)2. 2. Calendar year covered by the report.
NR 502.12(15)(b)3. 3. Annual quantities and types of raw materials received and compost produced, in tons. Tonnage estimates may be based on volume records where scale weights are not available.
NR 502.12(15)(b)4. 4. Annual quantity of compost sold, distributed or used, in tons, and quantity of class A compost sold, distributed or used.
NR 502.12(15)(b)5. 5. Copies of laboratory analyses of composted material.
NR 502.12(15)(b)6. 6. Any additional information required as a condition of the plan of operation approval.
NR 502.12 Note Note: Copies of the annual reporting form may be obtained from the department of natural resources, bureau of waste and materials management, 101 South Webster Street, P.O. Box 7921, Madison, Wisconsin 53707-7921, (608) 266-2111,, or online at
NR 502.12(16) (16)Class A compost. Finished compost may be designated and distributed as class A compost if it meets all of the following requirements:
NR 502.12(16)(a) (a) The compost is composed entirely of materials meeting the definition of “source-separated compostable materials" in s. NR 500.03 (219m).
NR 502.12(16)(b) (b) The compost is produced by one of the processes to reduce pathogens described in subd. 1. to 3., with temperature and retention time monitored and recorded each day until the temperature and retention time criteria are met:
NR 502.12(16)(b)1. 1. Windrow method consisting of an unconfined composting process utilizing periodic aeration and mixing. Aerobic conditions shall be maintained during the composting process. A temperature of 55°C, or 131°F, shall be maintained in the windrow for at least fifteen days. The windrow shall be turned at least five times during the high-temperature period.
NR 502.12(16)(b)2. 2. Mechanically aerated static pile method consisting of an unconfined composting process utilizing mechanically forced aeration of insulated compost piles. Aerobic conditions shall be maintained during the composting process. The temperature of the compost pile shall be maintained at a continuous minimum of 55°C, or 131°F, for at least three consecutive days.
NR 502.12(16)(b)3. 3. In-vessel method consisting of a confined compost process utilizing mechanical mixing of compost under controlled conditions. The minimum retention time in the vessel shall be 72 hours with the temperature maintained at 55°C, or 131 °F.
NR 502.12(16)(c) (c) The compost is tested in accordance with sub. (15) (a) 1. a. and b.
NR 502.12(16)(d) (d) The compost does not exceed any of the limits specified in Tables 1 or 2.
Table 1.
Test parameters for nonexempt compost facilities and class A compost - See PDF for table PDF
Table 2.
Maturity and stability testing for nonexempt facilities and class A compost - See PDF for table PDF
NR 502.12 History History: Cr. Register, January, 1988, No. 385, eff. 2-1-88; r. and recr., Register, June, 1996, No. 486, eff. 7-1-96; CR 05-020: am. (8) (a) 7. and (9) (a) 7. Register January 2006 No. 601, eff. 2-1-06; CR 10-128: am. (title), (1) (intro.), r. (1) (a) to (f), am. (2), (3) (title), (intro.), (a), (4) (title), (intro.), (c), (e) (intro.), r. and recr. (4) (e) 1. to 3., cr. (4) (e) 4., am. (5) (title), (intro.), (b), (c), (d), (e), (f) (intro.), 1., 2., (6) (title), (intro.), (b), (c), (e), (7) (title), (intro.), (a), (b), (c), r. and recr. (7) (e), (f), am. (8) (title), (a) (intro.), r. (8) (a) 4., 6., renum. (8) (a) 5., 7., 8. to be 4., 5., 6., r. and recr. (8) (b), cr. (8) (c), r. (9), am. (10) (intro.), (a) to (e), (h) 1., 3., (11) (intro.), (a), (b), r. and recr. (11) (d), cr. (11) (e), am. (12) (a), (b), (13) (title), (intro.), (b), (e), (f), (g), (h), (k), cr. (13) (m), (n), (o), (p), am. (14) (a), r. and recr. (15), cr. (16), r. and recr. Table 1 and Table 2 Register May 2012 No. 677, eff. 6-1-12; correction in (13) made under s. 13.92 (4) (b) 7., Stats., Register July 2015 No. 715.
NR 502.13 NR 502.13Municipal solid waste combustors.
NR 502.13(1)(1)General.
NR 502.13(1)(a)(a) No person may operate or maintain a municipal solid waste combustor unless the person complies with the requirements in s. NR 502.04 and obtains a plan of operation approval under sub. (3) and an operating license from the department.
NR 502.13(1)(b) (b) Owners and operators of new or expanded municipal solid waste combustor facilities having a design capacity of greater than 100 tons per day shall provide proof of financial responsibility for closure prior to licensure. Closure costs shall include the costs of removal, transport and ultimate disposal of wastes.
NR 502.13(1)(c) (c) Owners and operators of new or expanded municipal solid waste combustor facilities shall demonstrate compliance with the applicable locational criteria listed in sub. (2).
NR 502.13(2) (2)Locational criteria.
NR 502.13(2)(a)(a) No person may establish, construct or expand a municipal waste combustor within the following areas, except as otherwise specified within this chapter.
NR 502.13(2)(a)1. 1. Within a floodplain.
NR 502.13(2)(a)2. 2. Within 250 feet of any private water supply well, or within 1,200 feet of any public water supply well.
NR 502.13(2)(b) (b) Exemptions from the requirements of par. (a) 2. may be granted only upon demonstration by the applicant of circumstances which warrant the exemptions. Exemptions from compliance with par. (a) 1. may not be granted. The department may impose additional locational criteria if there is a significant potential for the facility to cause environmental pollution as defined in s. 299.01 (4), Stats., nuisance conditions or bird hazard to aircraft.
NR 502.13(3) (3)Plan of operation. No person may establish, construct or operate a municipal solid waste combustor or expand an existing facility prior to obtaining approval in writing from the department of a plan of operation for the facility. The plan of operation for the municipal solid waste combustor shall provide a design which complies with the operational requirements in sub. (4) and contain, at a minimum, the following:
NR 502.13(3)(a) (a) A map or aerial photograph of the area showing land use and zoning within 1/4 mile of the site. The map or aerial photograph shall be of sufficient scale to show all homes, industrial buildings, roads and other applicable details and the details shall be identified and indicated on the map or aerial photograph.
NR 502.13(3)(b) (b) A plot plan of the municipal solid waste combustor site including means of limiting access such as fencing, gates, natural barriers; methods of acceptably screening the facility from the surrounding area; general layout of equipment and flow pattern; road access; and location of existing and proposed utilities serving the municipal solid waste combustor.
NR 502.13(3)(c) (c) A report which shall include the following information:
NR 502.13(3)(c)1. 1. The legal description of the property where the municipal solid waste combustor will be located.
NR 502.13(3)(c)2. 2. Population, area and facilities to be served by the municipal solid waste combustor.
NR 502.13(3)(c)3. 3. Anticipated type and quantity of waste to be handled by the municipal solid waste combustor.
NR 502.13(3)(c)4. 4. Persons responsible for the municipal solid waste combustor operations.
NR 502.13(3)(c)5. 5. Methods of treating or disposing of any liquid wastes or waste waters resulting from the operation of the combustor.
NR 502.13(3)(d) (d) A description of appurtenances and procedures intended to store refuse beyond the end of the working day and to control dust, odors, fire outside the burning chamber and windblown materials.
NR 502.13(3)(e) (e) A description of methods of volume reduction including compaction, compression, baling, shredding, grinding, tamping, separating or classifying.
NR 502.13(3)(f) (f) A description of daily clean up procedures.
NR 502.13(3)(g) (g) A description of municipal solid waste combustor inspection and maintenance schedule and procedures.
NR 502.13(3)(h) (h) Detailed drawings and specifications of all structures, equipment and site.
NR 502.13(3)(i) (i) A report which includes furnace design criteria and expected performance data.
NR 502.13(3)(j) (j) Identification of the site at which the residue will be disposed and alternative sites available for use when the primary site is inoperative.
NR 502.13(3)(k) (k) For all new or expanded facilities, the plan of operation shall also include:
NR 502.13(3)(k)1. 1. The name of the emergency fire-fighting unit that will respond to fire calls at the facility.
NR 502.13(3)(k)2. 2. A discussion of the anticipated sequence of required events for facility closure.
NR 502.13(3)(k)3. 3. A detailed analysis in accordance with ch. NR 520 of the financial responsibility for facility closure. This shall include an itemized cost estimate for phased and final facility closure. All assumptions used in developing the cost estimates shall be justified.
NR 502.13 Note Note: Municipal solid waste combustors must also have the air management permits required under s. 285.60, Stats.
NR 502.13(4) (4)Operational requirements. No person may operate or maintain a municipal solid waste combustor except in conformance with the following minimum requirements, unless an exemption is granted by the department in writing:
NR 502.13(4)(a) (a) The municipal solid waste combustor shall be situated, equipped, operated and maintained in a nuisance-free manner.
NR 502.13(4)(b) (b) Adequate shelter and sanitary facilities shall be available for facility personnel.
NR 502.13(4)(c) (c) A sign shall be prominently posted at the entrance to the facility which indicates name, license number, hours of operation, necessary safety precautions and any other pertinent information.
NR 502.13(4)(d) (d) All incoming solid waste shall be confined to the designated storage area.
NR 502.13(4)(e) (e) All solid waste, except residue, shall be stored in conformance with s. NR 502.05 (5) or (6).
NR 502.13(4)(f) (f) Dust shall be controlled in all waste handling areas.
NR 502.13(4)(g) (g) Permanent records shall be maintained in accordance with sub. (7).
NR 502.13(4)(h) (h) Appropriate fire-fighting equipment shall be available in the storage and charging areas and elsewhere as needed.
NR 502.13(4)(i) (i) Arrangements shall be made with the local fire protection agency to provide adequate emergency fire-fighting forces.
NR 502.13(4)(j) (j) Means of communication with emergency facilities shall be provided.
NR 502.13(4)(k) (k) Adequate equipment shall be provided and used to clean the waste storage, waste handling, waste charging, and ash handling areas as may be required in order to maintain the plant in a sanitary condition.
NR 502.13(4)(L) (L) The charging openings as well as all equipment throughout the plant shall be provided with adequate safety equipment.
NR 502.13(4)(m) (m) The municipal solid waste combustor shall be designed and operated so that it will not cause a nuisance because of the emission of noxious odors, gases, contaminants or particulate matter or exceed emission limitations established by state air management rules in chs. NR 400 to 499.
NR 502.13(4)(n) (n) Residue shall be disposed of at a solid waste facility licensed by the department to accept the material or be handled by an alternate method approved in writing by the department. Approval shall be issued on a case-by-case basis after review of the information contained in sub. (6).
NR 502.13(4)(o) (o) All wastewater from the combustor shall be discharged into a sanitary sewer or other system approved in writing by the department.
NR 502.13(4)(p) (p) Upon completion of construction of a new municipal solid waste combustor and at least 10 days prior to initial operation, the department shall be notified to allow inspection of the combustor both prior to and during any performance tests and initial operation.
NR 502.13(4)(q) (q) Open burning of solid waste may not be conducted.
NR 502.13(4)(r) (r) An approved alternative method shall be used for solid waste disposal during any time that the municipal solid waste combustor is inoperable.
NR 502.13(4)(s) (s) The incoming waste shall be screened to eliminate unacceptable material from entering the municipal solid waste combustor such as hazardous waste, asbestos, explosive materials or other materials as defined in sub. (9).
NR 502.13(4)(t) (t) Residue storage at the municipal solid waste combustor shall be in accordance with the following:
NR 502.13(4)(t)1. 1. The residue shall be wetted at all times during storage to prevent dust emissions. The facility may use alternative methods of dust control that are approved by the department prior to implementation. Provisions shall be made to prevent the release of residue into the air in the residue handling areas.
NR 502.13(4)(t)2. 2. The storage area shall have an impervious surface on which the residue is stored and a collection system for any liquids coming into contact with the residue. All liquid that comes into contact with the residue which is not used as makeup water in the quench tank shall be collected and treated at a wastewater treatment plant approved by the department.
NR 502.13(4)(t)3. 3. Access to the temporary storage areas shall be restricted to authorized personnel only. Fencing or other means of control acceptable to the department shall be maintained around the storage facility.
NR 502.13(4)(u) (u) All treatment or mixing of residue shall be performed in a manner which controls air and water emissions.
NR 502.13(4)(v) (v) Treatment or mixing of residue at a facility other than at the municipal solid waste combustor shall require a processing license under s. NR 502.08.
NR 502.13(5) (5)Residue sampling.
NR 502.13(5)(a)(a) The owner or operator shall collect representative samples of residues produced by burning municipal solid waste for characterization required in sub. (6). The samples shall be collected over a minimum one-week period every quarter within 2 weeks of March 15, June 15, September 15 and December 15, except as provided in par. (f). Minimum 2 gallon volume samples shall be obtained hourly by a procedure approved by the department. The hourly samples shall be composited daily. Each daily sample shall then be composited together at the end of the testing period to result in a minimum of one representative sample. Compositing shall be performed in a manner acceptable to the department.
NR 502.13(5)(b) (b) Unless the residues are mixed as part of an internal, mechanical process, air pollution control equipment residue samples shall be collected separately from bottom-ash samples. If the mixing is part of an internal mechanical process, then the sampling shall be performed after the residue is mixed. If an ash treatment process occurs at the municipal solid waste combustor, then the sample shall be collected after treatment.
Published under s. 35.93, Stats. Updated on the first day of each month. Entire code is always current. The Register date on each page is the date the chapter was last published.