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NPDES Permits Required to Spray Aquatic Pesticides

January 23, 2009

A Sixth Circuit ruling will require an NPDES permit for applications of aquatic pesticides in and around rivers, lakes, and other waterbodies. The Court’s ruling in National Cotton Council v. EPA affects, among others, farmers, land managers and developers who routinely use the pesticides to protect their land.


The CWA requires a NPDES permit in order to discharge pollutants from point sources onto waters of the United States. In the past, EPA has not required a NPDES permit to apply of aquatic pesticides,[1] as long as these applications comply with a second law – the Federal Insecticide, Fungicide, and Rodenticide Act (“FIFRA”).[2]

In a 2001 decision called Headwaters, Inc. v. Talent Irrigation Dist.,[3] the Ninth Circuit held that aquatic herbicide residue left in water from pesticide applications was a “chemical waste” and thus a “pollutant” requiring a permit under the CWA. The Ninth Circuit declined, in Talent, to decide whether a pesticide that leaves no chemical residue in the water falls within the definition of a pollutant.

The following year, in League of Wilderness Defenders v. Forsgren,[4] the Ninth Circuit addressed whether an NPDES permit is required for the aerial application of insecticides to control pests, where some insecticide is inevitably discharged into waters. The court held that the application of insecticides over National Forest land constituted a “point source” discharge requiring an NPDES permit. The Forsgren court, however, did not address whether such insecticides were “pollutants,” assuming that they were.

In 2005, in Fairhurst v. Hagener,[5] the Ninth Circuit tackled the question remaining in Talent – namely, whether pesticides that are directly and intentionally applied to water bodies, in accordance with the requirements of FIFRA, are “chemical wastes”, and thus CWA “pollutants”, that require an NPDES permit. The Fairhurst court held that such pesticides that are intentionally applied to the nation’s waters, in compliance with FIFRA, and that produce no residue or unintended effects, are not “pollutants” requiring a CWA NPDES permit. The Court distinguished its previous finding in Talent on the grounds that, in Talent, the pesticide remained in the water after it performed its intended beneficial function.

The Aquatic Pesticide Rule

A year after Fairhurst was decided, EPA issued a final rule, on November 27, 2006, that exempted the application of aquatic pesticides in compliance with FIFRA from the CWA.[6] Specifically, EPA wrote that an NPDES permit was not required for: (1) the application of pesticides directly to water in order to control pests; or (2) the application of pesticides to control pests present over or near water (such as via aerial application) where a portion of the pesticides would unavoidably be deposited into waters. EPA intended the second circumstance, among other things, to cover pesticide spraying to control non-native plants growing at the water’s edge because some pesticide would unavoidably enter the water as a result of herbicide application.

EPA made clear that its rule was based on its longstanding policy that pesticides applied according to its federal label are not CWA “pollutants” and, thus, do not require NPDES permits. EPA explained that aquatic pesticides that are sprayed or otherwise applied consistent with FIFRA are not “chemical wastes” because “they are products that EPA has evaluated and registered for the purpose of controlling target organisms, and are designed, purchased, and applied to perform that purpose.”[7] Further, EPA stated that aquatic pesticides are not “biological materials” because, to find otherwise, “would mean that biological pesticides are pollutants, which chemical pesticides applied in the same circumstances are not.”[8] Finally, EPA wrote that, while residual material remaining following pesticide application may be considered “pollutants”, the pesticide itself is not a pollutant at the time of discharge. Accordingly, EPA encouraged treating the residual as a nonpoint source pollutant for which no NPDES permit would be required.[9] EPA’s final rule became effective January 26, 2007.

National Cotton Council v. EPA

Environmental and industry groups subsequently challenged EPA’s final rule in eleven circuit courts throughout the United States. The petitions for review were consolidated in the Sixth Circuit by an order of the Judicial Panel on Multidistrict Litigation. National Cotton Council v. EPA, 2009 U.S. App. LEXIS 45 (6th Cir. 2009). A number of industry groups also intervened in support of the final rule.[10]

Environmental Petitioners[11] argued that: (1) EPA exceeded its authority under the CWA by excluding pesticides from the definition of a CWA “pollutant”; (2) EPA exceeded its authority under the CWA by determining that, while pesticides are discharged from a point source, the residue of such pesticides is a “nonpoint source pollutant”; and that (3) EPA may not exempt FIFRA compliant pesticide applications from the reach of the CWA. Industry Petitioners[12] argued that EPA’s final rule was arbitrary and capricious because, under that rule, pesticides applied in violation of FIFRA are “pollutants” while the same pesticides applied in compliance with FIFRA are not. [13]

The Court examined whether the CWA unambiguously includes pesticides within its definition of “pollutant”, and concluded that it does.[14] The CWA defines a “pollutant” to include “chemical wastes” and “biological materials.”[15] After analyzing the plain meaning of the word “waste”, the court found that the CWA definition of “chemical waste” includes “discarded chemicals, superfluous chemicals, or refuse or excess chemicals.”[16] Like the Ninth Circuit in Fairhurst, the Sixth Circuit therefore, found: “so long as the chemical pesticide is intentionally applied to the water [to perform a particular useful purpose] and leaves no excess portions after performing its intended purpose [] it is not a ‘chemical waste’…and does not require an NPDES permit.”[17]

However, the Court decided that excess chemical pesticide and pesticide residue may be “pollutants”.[18] The Court observed that there are at least two situations in which excess pesticide or pesticide residue would meet the CWA definition of “chemical wastes”: (1) where chemical pesticides are applied to land or air, and excess pesticides or pesticide residue is subsequently deposited into jurisdictional waters; and (2) where pesticides residue remains following the direct application of chemical pesticides to jurisdictional waters.[19]

Next, the Court examined the plain meaning of the term “biological materials” and decided that that term unambiguously includes biological pesticides and their residues that are discharged into water. The Court therefore concluded that the application of biological pesticides should not be exempted from NPDES permitting requirements.[20]

Finally, the Court rejected EPA’s argument that excess and residual pesticides should be exempt from NPDES permitting requirements because they do not qualify as pollutants at the time of discharge. The Court found: “[t]here is no requirement that the discharged chemical, or other substance, immediately cause harm to be considered as coming from a ‘point source.’ Rather, the requirement is that the discharge come from a ‘discernable, confined, and discrete conveyance,’ 33 U.S.C. § 1362(14), which is the case for pesticide applications.”[21] Thus, the Court found that EPA’s attempt to inject a temporal requirement for the discharge of pollutants into water was unsupported by the CWA.

In light of the statutory language, the Court held that EPA’s final rule was not a reasonable interpretation of the CWA since the plain language of the terms “chemical waste” and “biological materials” unambiguously include aquatic pesticides. Accordingly, the Court vacated EPA’s final rule. The Court did not analyze arguments addressing the relationship between the CWA and FIFRA.


Following the Sixth Circuit’s decision, applicators will need an NPDES permit to apply aquatic pesticides into, around, and over water in most instances. NPDES permits will not be required, however, for applications of chemical pesticides that leave no residue in receiving waters. States are expected to review their current NPDES permitting requirements for aquatic pesticide use in light of the court’s decision. [22]

For more information on this and other water quality and permitting issues, please contact any member of Marten Law Group’s Water and Wetlands Practice Group.

[1] 71 Fed. Reg. 68,483 (Nov. 27, 2006) (to be codified at 40 C.F.R. Part 122).

[2] 7 U.S.C. § 136 et seq.

[3] 243 F.3d 526 (9th Cir. 2001).

[4] 309 F.3d 1181 (9th Cir. 2002).

[5] 422 F.3d 1146 (9th Cir. 2005).

[6] 71 Fed. Reg. 68,483

[7] 71 Fed. Reg. 68,483, 68,486.

[8] Id.

[9] Id. at 68,487.

[10] 2009 U.S. App. LEXIS 45, *10.

[11] Environmental Petitioners are Baykeeper, Californians for Alternatives to Toxics, Californian Sportsfishing Protection Alliance, National Center for Conservation Science and Policy, Oregon Wild, Saint John’s Organic Farm, Waterkeeper Alliance, Inc., Peconic Baykeeper, Inc., Soundkeeper, Inc., Environmental Maine, and Toxics Action Center.

[12] Industry Petitioners are Agribusiness Association of Iowa, BASF Corporation, Bayer CropScience LP, CropLife America, Delta Council, Eldon C. Stutsman, Inc., FMC Corporation, Illinois Fertilizer & Chemical Association, The National Cotton Council of America, Responsible Industry for a Sound Environment, Southern Crop Production Association, and Syngenta Crop Protection, Inc., LP.

[13] 2009 U.S. App. LEXIS 45, *16.

[14] 2009 U.S. App. LEXIS 45, *19-28.

[15] 33 U.S.C. § 1362(6).

[16] Id., at *22 (internal quotations omitted).

[17] Id. (internal quotations and citations omitted).

[18] Id.

[19] Id., at *23-24.

[20] Id., at *25-26.

[21] Id., at *30.

[22] While several states, including Washington State, California, Oregon, and Nevada, developed NPDES permit programs for aquatic pesticides following the Ninth Circuit decisions in Talent and Forsgren, other states have not issued permits to aquatic pesticide applicators. Washington State continued to issue NPDES permits for applications of aquatic pesticides pending the outcome in National Cotton Council. See Washington State Department of Ecology, “Focus on State’s Response to EPA Rule on Aquatic Pesticide Permitting,” Pub. No. 07-10-013 (February 2007).

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