## Facts

- Maple Leaf Farms, Inc. operated two large duck-growing facilities in Wisconsin producing roughly 91,000 tons of manure annually.
- Wisconsin’s WPDES program (Wis. Stat. ch. 283) prohibits discharges of pollutants to “waters of the state” without a permit and authorizes permit conditions to control such discharges.
- The Wisconsin Department of Natural Resources (DNR) determined Maple Leaf’s operations discharged pollutants to state waters through runoff and percolation/leaching to groundwater.
- DNR issued WPDES permits requiring runoff-control structures and waste storage and management practices.
- The permits also imposed conditions governing land application of Maple Leaf’s manure on both Maple Leaf-owned land and off-site farmland where Maple Leaf arranged manure spreading through contracts with other farmers.
- Maple Leaf did not dispute DNR’s authority to regulate discharges and manure management at its facilities, but challenged DNR’s authority to regulate off-site land application on land Maple Leaf did not own.
- Maple Leaf argued that regulating off-site land application exceeded what federal Clean Water Act CAFO/NPDES rules required and improperly made Maple Leaf responsible for compliance on other farmers’ land.
- The circuit court upheld DNR’s authority and the permit conditions; Maple Leaf appealed.

## Issues

1. Whether Wis. Stat. ch. 283 authorizes DNR to impose WPDES permit conditions regulating land application of a permittee’s manure on off-site farmland not owned by the permittee when such application may cause discharges to waters of the state.
2. Whether such off-site land-application conditions conflict with, or are preempted by, the federal Clean Water Act and federal CAFO/NPDES regulations.
3. Whether manure distributed for off-site land application should be treated as a regulated pollutant/discharge when it reaches state waters through runoff or leaching, rather than as an unregulated “product” once it leaves the facility.

## Decision

- The Wisconsin Court of Appeals affirmed the circuit court’s judgment upholding DNR’s permit conditions.
- The court held DNR had authority under Wis. Stat. ch. 283 to regulate land application of Maple Leaf’s manure, including on off-site farmland, where the application may result in a discharge of pollutants to waters of the state.
- The court held Wisconsin’s approach did not conflict with federal law; states may impose requirements more stringent than federal Clean Water Act minimums.
- The court treated manure as a “pollutant” when it enters, or is likely to enter, waters of the state through runoff or leaching, regardless of where it is land-applied.

## Legal Principles

- WPDES permitting authority under Wis. Stat. ch. 283 focuses on preventing discharges of pollutants to “waters of the state” and is not limited by property ownership boundaries when regulating activities that cause or risk such discharges.
- Animal waste/manure is a pollutant subject to regulation when it is discharged to state waters through runoff or percolation to groundwater.
- A state administering an NPDES-analog program may adopt and enforce standards and permit conditions more protective than federal Clean Water Act requirements, absent a direct conflict.
- Permit conditions may require a permittee to implement manure-management controls tied to the permittee’s generation and arranged disposal/application of manure, including off-site land application that poses a discharge risk.
- Courts may defer to a reasonable agency interpretation of its enabling statute when consistent with statutory text and purpose.

## Conclusion

The court upheld DNR’s inclusion of off-site manure land-application requirements in Maple Leaf’s WPDES permits, ruling that Wisconsin law authorizes permit conditions aimed at preventing pollutant discharges to state waters wherever the permittee’s manure is applied, and that the state’s more stringent controls do not conflict with federal Clean Water Act requirements.


Maple Leaf Farms, Inc. v. Wis. Dep’t of Nat. Res., 633 N.W.2d 720 (Wis. Ct. App. 2001)