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Oregon DEQ and U.S. EPA Issue New Pesticide General Permits

February 9, 2012


Final National Pollutant Discharge Elimination System Pesticide General Permits Issued by State of Oregon Department of Environmental Quality and U.S. Environmental Protection Agency for Point Source Discharges From the Application of Pesticides.

DEQ permit available at:

EPA permit available at:

On October 31, 2011, the Oregon Department of Environmental Quality ("DEQ") and the United States Environmental Protection Agency ("EPA") each issued a final National Pollutant Discharge Elimination System ("NPDES") Pesticide General Permit ("PGP") covering certain pesticide applications under the Clean Water Act ("CWA"). The new permits regulate applications of pesticides that result in point source discharges to waters of the State (under DEQ's permit) or waters of the United States (under EPA's permit). Specifically, the permits regulate applications of biological and chemical pesticides in, over, or near water, to control mosquitoes and other flying insects, weeds and algae, nuisance animals and forest canopy pests.

An NPDES permit is not required for discharges resulting from agricultural runoff and irrigation return flow, both of which may contain pesticides, because the CWA specifically exempts such discharges from permitting requirements. Also, pesticide applications to land that do not result in point source discharges to waters of the United States (e.g. to control pests on agricultural crops, forest floors, or range lands) do not require NPDES permit coverage. Accordingly, many agricultural operations may not need NPDES permits for pesticide applications.

Coverage Areas
EPA's PGP provides permit coverage in areas where EPA is the NPDES permitting authority, including six states (Alaska, Idaho, Massachusetts, New Hampshire, New Mexico, and Oklahoma), most Indian lands and U.S. Territories, and certain federal facilities. The remaining states, including Oregon, are authorized to issue their own NPDES pesticide permits. Pursuant to that authority, DEQ issued a permit that covers regulated pesticide applications within the State of Oregon, with the exception of Indian lands within the state (the EPA permit applies to such lands and includes special conditions for discharges to waters within the Warm Springs Reservation and the Confederate Tribes of the Umatilla Indian Reservation). DEQ also plans to issue a related Irrigation District General Permit sometime in 2012 to cover the application of certain aquatic pesticides into irrigation systems operated by districts formed under Oregon Revised Statutes Chapter 545 or by entities previously covered by an individual permit for the application of aquatic pesticides. This following discussion focuses on the requirements of the state permit, and the term "PGP" refers to DEQ's PGP unless otherwise noted.

Permit Terms and Conditions
The PGP covers five main categories of pesticide applications: (1) mosquito and flying insect pest control; (2) weed and algae control within 3 feet of water's edge; (3) nuisance animal control within 3 feet of water's edge; (4) forest canopy pest control when a portion of the pesticide will unavoidably be applied over and deposited in water; and (5) area-wide pest control by aerial application to avoid substantial and widespread economic and social impact, when a portion of the pesticide will unavoidably be applied over and deposited in water.

The PGP regulates "operators," defined as "any owner or entity with operational control over the decision to perform a pesticide application that is covered under this permit or has the day-to-day operational control of activities that are necessary to ensure compliance with the permit." Landowners who do not have legal authority to control the application of pesticides and are not directly financing the application are not considered "operators" (e.g. when a governmental entity sprays for mosquitoes over a person's property).

All operators that conduct covered pesticide applications are subject to the permit, but only large-scale pesticide applicators, federal and state agencies, and districts responsible for pest control are required to register with DEQ and pay fees for permit coverage. The permit provides annual treatment thresholds for determining whether registration is required. The annual threshold for mosquitoes/flying insects, forest canopies, and area-wide aerial applications is 6400 acres of surface treatment area. The threshold for weed and algae control and nuisance animals is 20 acres of surface treatment area for in-water applications or 20 linear miles of treatment area for in-water/ water's-edge applications.

Federal and state agencies, and some special districts, were required to register by submitting an application to DEQ on or before January 9, 2012. Operators whose pesticide application will exceed the annual treatment area threshold are required to submit an application to DEQ no less than 45 days before exceeding the annual threshold. DEQ will review applications within 30 days and will approve or deny registration under the PGP. In addition to an initial application fee, registered operators will be required to pay an annual fee, and to apply for renewal of coverage under the permit when it expires in 2016.

The PGP contains both technology-based effluent limitations and water-quality based effluent limitations. The technology-based effluent limitations require the operator to minimize discharges of pesticides to waters of the United States through the use of "pest management measures," including: (1) limiting use to the optimal amount of pesticide consistent with the pesticide label; (2) performing maintenance activities in a manner that reduces leaks and spills; (3) maintaining pesticide application equipment in proper operating condition; and (4) assessing weather conditions (e.g. temperature, precipitation and wind speed) in the treatment area to ensure application is consistent with all applicable requirements. Additionally, operators that are required to register must implement additional pest management measures at a more intensive level to identify the problem, evaluate pest management options and minimize pesticide use. Registered operators also have enhanced record-keeping responsibilities.

The water-quality based effluent limitations in the PGP are narrative in nature and require an operator to meet applicable water quality standards. The expectation is that if an operator follows the permit's technology-based effluent limitations, there will be no violation of applicable water quality standards. However, if violations occur, the DEQ may impose additional requirements on the operator.

Registered operators must prepare a Pesticide Discharge Management Plan ("PDMP") by the time the application for registration is submitted to DEQ. The PDMP describes how an operator will implement the effluent limitations in the permit. An operator who is required to prepare a PDMP must review and update the plan at least once per calendar year.

Limitations on Permit Coverage
Several categories of pesticide-related discharges are not covered under the PGP. These include: (1) discharges from a pesticide application if the affected waterway is identified as impaired by a substance which either is an active ingredient in that pesticide or is a degradate of such an active ingredient (impaired waters are those identified by a state, tribe, or EPA pursuant to section 303(d) of the CWA as not meeting applicable state or tribal water quality standards); (2) certain discharges to waters designated by a state or tribe as Tier 3 (Outstanding National Resource Waters) for antidegradation purposes under Title 40 of the Code of Federal Regulations; (3) discharges that are likely to adversely affect species that are federally-listed as endangered or threatened under the Endangered Species Act or habitat that is federally-designated as critical under the ESA; and (4) discharges covered under another NPDES permit.