On October 31, 2011 the Department of Natural Resources (DNR) issued general permits covering the application of pesticides to or near waters of the State under the Clean Water Act.

In the past, this application of pesticides near or in water had been exempt from the Clean Water Act regulation. These general permits are now needed because of a court case striking down EPA’s regulations that exempted the pesticide applications from Clean Water Act requirements. The case determined that any biological pesticide or chemical residue of a pesticide in Waters of the United States was subject to the Clean Water Act and that EPA exceeded its authority when it exempted the discharge from regulation under the Clean Water Act.

The clear example of where a permit is now required is where there is an application of pesticides to a lake or river to control nuisance aquatic plants. What is not so clear is where there is an application of pesticides near water where the residue from the pesticides could potentially get into the water. The definition of what constitutes “near waters of the State” is not black and white. If there is the potential for pesticides to get into the water, we recommend that you examine whether a permit is needed and err on the side of applying for coverage under the General Permit. The application process for a general permit should be relatively easy, but there may be some new permit requirements, such as record keeping and reporting to the Department of Natural Resources.

There are four general permits covering the application of pesticides to deal with:
1) Nuisance or invasive aquatic plants, algae and bacteria;
2) Detrimental or invasive aquatic animals;
3) Forest canopy pests; and,
4) Mosquitoes or other flying insects.

Examples of some pesticide applications that may need to be covered by a general permit include:

• Pesticide treatment of a municipal wastewater or cooling water lagoon
• Pesticide treatment for mosquitoes (retention/detention ponds)
• Pesticide treatment to prevent or control aquatic invasive species
• Pesticide treatment to deal with clogged intakes

Pesticides are generally divided into two types – terrestrial and aquatic. Typically, when applying an aquatic pesticide, you will need a WPDES general permit from the DNR as well as a ch. NR 107 permit. When applying a terrestrial pesticide that does not get into the surface water, you will not need a permit. The application of a terrestrial pesticide that gets into water is not covered under the general permit. This would be considered a violation of the label of the pesticide and subject to prosecution by the Department of Agriculture, Trade and Consumer Protection (DATCP). Additionally, an application of an aquatic pesticide that is not in accordance with its label is not covered under the DNR’s general permit. This would be a violation that would also be subject to prosecution by DATCP and potentially the DNR depending on the harm to the environment.

You also may not need to apply for permit coverage if you are not the one actually doing the application of pesticides. If you are using a licensed pesticide applicator, they should have coverage under a general permit. You should confirm with your contractor who is expected to get the permit coverage and confirm that your project is covered under their grant of coverage.

Other types of pesticide applications that are not covered by the general permit but would probably need an individual permit from the DNR include:

• Application of pesticides to outstanding or exceptional resource waters for the purposes of controlling native Wisconsin species
• Application of pesticides that would result in significant adverse impact to wetlands where the wetland protection requirements of ch. NR 103, Wis. Adm. Code, would not be met
• Application of pesticides to a water body that is impaired for that pesticide. (Currently, there are no waters identified in Wisconsin as impaired for a pesticide.)

Also, any application of a pesticide located within Indian Country are not covered by the general permit or an individual permit. These applications would be regulated by the United States Environmental Protection Agency or a tribe that has been delegated the authority to regulate pollutant discharges within its territory.

The process for requesting coverage under the general permits should be relatively simple. The Department of Natural Resources is preparing an application for a request for coverage. The Department will review the information submitted and will grant or deny coverage under the general permit. As this is a new process, initially, an applicant should allow for 60 days prior to the start of the treatment for the Department to review and grant the application. Coverage under the WPDES general permits is good for five years. Also, for some aquatic treatment, an additional permit under ch. NR 107 may be needed.

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