Oregon DEQ General Permit For Pesticide Application

The Oregon Department of Environmental Quality (DEQ) has released and has requested public comments on its proposed National Pollutant Discharge Elimination System (NPDES) pesticide general permit. The proposed permit is in response to the January 2009 Sixth Circuit Court ruling that NPDES permits are required for all biological and chemical pesticide applications that leave a residue or excess pesticide in water when the applications are made in, over or near water. The court required permits to be effective no later than April 9, 2011.

DEQ has proposed to issue the general permit for the following pesticide applications:

1. Mosquito and other flying insect pest control
2. Weed and Algae Control for invasive or other nuisance weeds, algae and pathogens in water and at the water’s edge.
3. Nuisance Animal Control for the control of invasive or other nuisance animals and pathogens in water and at the water’s edge.
4. Forest Canopy Pest Control for the control of pest species by using aerial application of a pesticide over a forest environment or from the ground.
5. Area-Wide Pest Control for the control of pest species by using aerial pesticide application to cover a large area to avoid substantial and widespread economic and social impact.
   

The permit, once finalized, may affect both public and private entities that use pesticides for the types of pesticide applications listed above.

Operators who conduct pesticide applications above an annual threshold will need to register with DEQ. The Annual Treatment Area Thresholds proposed are:

Mosquitoes and Other Flying Insect Pests - 6,400 acres of treatment surface area
Weed and Algae Control (Excludes irrigation districts formed under ORS 545)
In Water - 20 acres of surface treatment area
In Water and at Water’s Edge: - 50 linear miles of treatment area.
Nuisance Animal Control:
In Water - 20 acres of treatment surface area
In Water and at Water’s Edge - 50 linear miles of treatment surface area.
Forest Canopy Pest Control - 6,400 acres of treatment surface area
Area Wide Pest Control - 6,400 acres of treatment surface area.

The draft permit requires all operators to minimize pesticide discharges by:

• using the optimal amount of pesticide
• preventing leaks and spills
• calibrating equipment
• use integrated pest management
• minimize the discharge of pesticides
• meet water quality standards
• maintain certain records
• report adverse incidents

Operator are also required to notify private and domestic drinking water users prior to the use of pesticides that have potable water use restrictions. All operators are required to conduct site monitoring and visual monitoring to ensure that pesticide use is minimized.

The permit sets a threshold that requires the largest pesticide users under each type of pest control to:

• submit an application for registration and pay fees
• implement integrated pest management
• develop a pesticide discharge management plan
• submit annual reports

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