Saturday, December 4, 2010

Annual Treatment Area Thresholds In Proposed ADEQ Pesticide Application Permit

In December 2010, the Arizona Department of Environmental Quality (ADEQ) released a proposed general permit applicable to point source discharges of pesticides to the waters of the State (Permit No. AZG2011-001). This permit applies to pesticide application on or near surface waters in Arizona.

Read a summary of the proposed ADEQ general permit for application of pesticides


Read background on pesticide permitting requirements


Operators required to submit an NOI that meet or exceed the annual threshold(s) must comply with the Integrated Pest Management (IPM) Practices listed in the permit. In addition, operators that exceed annual thresholds also prepare and implement a Pesticide Discharge Management Plan (PDMP).

The Annual Treatment Area Thresholds proposed by ADEQ in the draft permit are:

Mosquitoes and Other Flying Insect Pests: 640 acres of treatment area

Aquatic Weed and Algae Control:

In Water: 20 acres of treatment area

At Water’s Edge: 20 linear miles of treatment area at water’s edge

Aquatic Nuisance Animal Control:

In Water: 20 acres of treatment area

At Water’s Edge: 20 linear miles of treatment area at water’s edge

Forest Canopy Pest Control: 640 acres of treatment area

Discharges to impaired waters or Outstanding Arizona Waters: Any amount




Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

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