Wisconsin Administrative Code
Department of Natural Resources
NR 600-699 - Environmental Protection - Hazardous Waste Management
Chapter NR 667 - Standards For Owners And Operators Of Hazardous Waste Facilities Operating Under A Standardized License
Subchapter G - Closure
Section NR 667.0117 - How do I certify closure?

Within 60 days of the completion of final closure of each unit under a subch. J of ch. NR 670 standardized license, you shall submit to the department, by registered mail, a certification that each hazardous waste management unit or facility, as applicable, has been closed following the specifications in the closure plan. Both you and a qualified professional engineer shall sign the certification. You shall furnish documentation supporting the independent registered professional engineer's certification to the department upon request until the department releases you from the financial assurance requirements for closure under s. NR 667.0143(9).