Wis. Admin. Code Department of Natural Resources NR 214.08
Land treatment systems which will no longer be used shall be properly abandoned within 2 years of the date on which waste material was last applied. The department may require a plan that includes a procedure to properly identify the presence and characteristics of any accumulated solid matter and provide appropriate removal, disposal, treatment or recycling alternatives in accordance with applicable solid and hazardous waste laws. All recycling, treatment and disposal shall be conducted so as to protect public health and the environment. Unless otherwise directed by the department, soil that has been contaminated by a land treatment system shall be remediated in compliance with ch. NR 720 when the land treatment system is abandoned. The plan shall also address site restoration and any landscaping that will prevent groundwater impacts, accumulation of standing water or runoff. The department may require groundwater monitoring for a period of time after abandonment of the land treatment system to assess groundwater impacts. The design, installation, construction, abandonment and documentation of all monitoring wells shall be in accordance with the requirements of ch. NR 141.
Wis. Admin. Code Department of Natural Resources NR 214.08