Wisconsin Administrative Code
Department of Agriculture, Trade and Consumer Protection
ATCP 20-54 - Agricultural Resource Management
Chapter ATCP 51 - Livestock Facility Siting
Subchapter II - Livestock Facility Siting Standards
Section ATCP 51.14 - Odor and air emissions

Universal Citation: WI Admin Code ยง ATCP 51.14

Current through August 26, 2024

(1) ODOR STANDARD. Except as provided in subs. (2) to (4), a livestock facility shall have an odor score of at least 500. The operator shall calculate the odor score according to Appendix A, worksheet 2, or by using the equivalent spreadsheet provided on the department's website. An application for local approval shall include worksheet 2 or the spreadsheet output.

Note: The spreadsheet equivalent of Appendix A, worksheet 2 is available on the department's website at http://livestocksiting.wi.gov/.

Odor score is based on predicted odor generation (based on size and type of livestock facility), odor practices, and the proximity and density of "affected neighbors." See Appendix A, worksheet 2.

An odor score is a predictive estimate. The standard in sub. (1) applies only for purposes of local livestock facility siting decisions under this chapter. Failure to comply with the standard in sub. (1) does not constitute evidence of a public or private nuisance, negligence, or a taking of property.

Odor control practices may also control air pollution emissions. The department will work to coordinate odor and air emissions field research with DNR, the Wisconsin agricultural stewardship initiative (WASI), and the University of Wisconsin. The department will consider research results when it reviews this chapter at least once every 4 years (see s. 93.90(2) (c), Stats.). As part of its review, the department will consult with an advisory committee that includes representatives of livestock producers, local government and environmental interests. The department will consider amendments to this rule, as appropriate, based on research findings.

(2) EXEMPTIONS. The odor standard in sub. (1) does not apply to any of the following livestock facilities unless the facility operator voluntarily completes and submits worksheet 2 or the equivalent spreadsheet output with the operator's application for local approval:

(a) A new livestock facility with fewer than 500 animal units.

(b) An expanded livestock facility with fewer than 1,000 animal units.

(c) A livestock facility in which all livestock structures will be located at least 2,500 ft. from the nearest affected neighbor.

Note: "Affected neighbors" (ATCP 51.01(2)) are residences or "high-use buildings" (ATCP 51.01(16)) other than those owned by the livestock operator or by persons who agree to be excluded from odor score calculations under sub. (1).

(3) CLUSTERS. If all of the livestock structures in a livestock facility are divided among 2 or more clusters, such that no cluster is located closer than 750 feet to any other cluster, an operator may choose to calculate an odor score under sub. (1) for each cluster rather than for the entire livestock facility. Each cluster shall comply with the odor standards in sub. (1).

Note: For example, a dairy operator can take advantage of sub. (3) if a proposed dairy facility includes a milking operation (cluster 1) and a heifer facility (cluster 2) located 800 feet from each other.

(4) LOCAL DISCRETIONARY CREDIT.

(a) Notwithstanding sub. (1), a political subdivision may in its discretion approve a livestock facility with an odor score of less than 500, provided that the odor score is not less than 470.

(b) If a political subdivision exercises its discretionary authority under par. (a), its written decision under s. ATCP 51.34(3) shall state the reason or reasons for that exercise of discretionary authority.

(c) The livestock facility siting review board may not review any of the following under s. 93.90(5), Stats.:
1. A political subdivision's exercise, or refusal to exercise, discretionary authority under par. (a).

2. The adequacy of the political subdivision's stated reasons under par. (b) for exercising discretionary authority under par. (a).

Note: A political subdivision must approve a livestock facility that meets the odor standard under sub. (1), assuming that the facility meets other livestock facility siting standards under this chapter (seeATCP 51.34(1)).

A political subdivision may not approve a livestock facility that fails to meet the odor standard under sub. (1), except that the political subdivision may exercise its discretionary authority under sub. (4) (a) in favor of an applicant if it chooses to do so. For example, a political subdivision may exercise its discretionary authority under sub. (4) (a) based on factors such as community tolerance, the applicant's near attainment of a standard, innovative odor control practices, local land use plans, or the applicant's past reputation for good management and community relations.

(5) CREDITS FOR ODOR CONTROL PRACTICES. In the calculation of predicted odor under sub. (1), an operator may claim credit for all of the following:

(a) Odor control practices, identified in Appendix A, worksheet 2, which the operator agrees to implement. For each odor control practice, the operator may claim a credit specified in Appendix A, worksheet 2.

(b) An odor control practice not identified in Appendix A, worksheet 2 if the department pre-approves a credit for that practice. The operator shall claim the pre-approved credit according to the procedure specified in Appendix A, worksheet 2.

(c) An operator seeking department approval under par. (b) shall submit all of the following to the department in writing:
1. A clear description of the odor control practice for which the operator seeks an approved credit.

2. Scientific evidence to substantiate the efficacy of the odor control practice under relevant conditions.

(d) The department may approve a credit for an odor control practice under par. (b) if, in the department's opinion, there is adequate scientific evidence to show that under relevant conditions the practice will result in odor reduction commensurate with the approved credit. The department shall grant or deny the request within 90 days after the department receives the request.

Note: An odor control practice credit under sub. (5) is expressed, in the odor score calculation in Appendix A, worksheet 2, as a multiplier value (the lower the multiplier, the greater the benefit to the livestock operator).

(6) FUTURE REFERENCE POINTS.

(a) Whenever an operator seeks local approval for the expansion of a livestock facility previously approved under this chapter, the operator may calculate an odor score under sub. (1) by reference to the same affected neighbors referenced in the odor score calculation for the prior local approval. The operator is not required to include, in the new odor score calculation, an affected neighbor that was not referenced in the odor score calculation for the prior local approval.

(b) Paragraph (a) applies regardless of any change in ownership of the livestock facility since the prior local approval, and regardless of the amount of time that has passed since the prior local approval, provided that the prior local approval has not been lawfully withdrawn for good cause under s. ATCP 51.08(2) or 51.34(4) (b).

Note: The odor score calculation in Appendix A, worksheet 2 is partly based on the proximity and density of affected neighbors" (seeATCP 51.01(2)). An application for local approval documents those affected neighbor" reference points. Subsection (6) protects an operator against the effects of encroaching development, without regulating that development directly.

A local government must keep a complete record of each local approval for at least 7 years, and must file with DATCP a copy of each approval (including the application on which it was based). The local government must also provide the livestock operator with documentation of the local approval, including the maps on which the approval was based (see s. ATCP 51.34(3) (b)). The approved maps document the "odor score" reference points for purposes of sub. (6).

The livestock operator can record the local approval (including mapped "odor score" reference points) with the local register of deeds, and can convey the documentation to subsequent purchasers. In those ways, an operator can document previously-approved "odor score" reference points for purposes of a subsequent expansion.

(7) PRESUMPTION. For purposes of local approval, a livestock facility is presumed to comply with this section if the application for local approval complies with s. ATCP 51.30.

Under s. ATCP 51.30, an application must be complete, credible and internally consistent. The application must include, among other things, a worksheet (or equivalent spreadsheet output) that shows compliance with this section. See Appendix A, worksheet 2. Local approval is conditioned upon compliance in fact (see s. ATCP 51.34(4)). The presumption in sub. (7) may be rebutted by clear and convincing evidence in the record (see s. ATCP 51.34 and 51.36).

Disclaimer: These regulations may not be the most recent version. Wisconsin may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.