Wis. Admin. Code NR § 204.09
Alternative uses of sludge such as land application on sod farms, nurseries, Christmas tree plantations, mined land reclamation sites, restoration of construction sites or other drastically disturbed sites, research plots, highway right-of-ways and medians, fallow lands, set-aside lands as covered by the Acreage Conservation Reserve (ACR) program, final cover at landfills and use in building materials may not be conducted unless department approval is obtained. Sludge used to generate energy may be approved on a case-by-case basis. Department approval will consider factors such as the nature of the alternative use proposed, sludge quality, number of applications that are proposed, loading of pollutants to the land, air and water, and the proximity to waters of the state. Proposals for alternative uses of sludge may include the land application site evaluation information as required by s. NR 204.06(6) and shall include any additional information that would allow the department to make a determination that the proposed use is beneficial and will not result in detrimental effects to the environment, public health or wildlife.
Wis. Admin. Code Department of Natural Resources § NR 204.09