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February 25, 2013

Court of Appeals Issues Landmark Ruling Vacating Biological Opinion Concerning Effects of Three Pesticides on Salmon Species

Bergeson & Campbell, P.C.

On February 21, 2013, a three judge panel of the Fourth Circuit Court of Appeals issued a unanimous landmark decision in Dow Agrosciences v. National Marine Fisheries Service setting aside a Biological Opinion (BiOp) prepared by the National Marine Fisheries Service (NMFS) that found that use of the pesticides chlorpyrifos, diazinon, and malathion could jeopardize the viability of certain species of salmon and their habitat. The decision will have significant implications for the government and registrants alike.

The court determined that the BiOp was arbitrary and capricious because the NMFS failed to provide an adequate explanation concerning three critical choices:

  • Use of a model that assumed salmon are continuously exposed for 96 hours without explaining how this assumption correlates with exposure conditions in the real world;
  • Use of older monitoring data for the three pesticides that do not reflect the effect of mitigation measures that were implemented during reregistration; and
  • Inclusion in recommendations for additional mitigation of uniform buffer zones for all types of water, without regard to actual proximity to key salmon habitat or adequate consideration of the economic consequences.

This new decision will have far-reaching consequences because of the large number of pesticides that may be subject to referral to either the NMFS or the Fish and Wildlife Service (the Services) in connection with previous actions by the U.S. Environmental Protection Agency (EPA) during pesticide reregistration or future actions by EPA during registration review. When EPA takes such a registration action, Endangered Species Act (ESA) Section 7(a)(2) requires EPA to determine, in consultation with the Services, that the action is not likely to jeopardize the continued existence of any endangered or threatened species. Current procedures require EPA scientists to make an initial threshold determination whether or not continued registration “might” have such an effect, followed by referral to the Services for a formal consultation in instances where this threshold is met.

The new decision is an outgrowth of litigation concerning the effect of pesticides on endangered or threatened species that stretches back to 2001. In Washington Toxics Coalition v. EPA, a District Court in Washington and the Ninth Circuit Court of Appeals ordered EPA to determine whether it should have consulted with NMFS concerning reregistration of 55 specific pesticides. EPA subsequently decided that 37 of these pesticides (including chlorpyrifos, diazinon, and malathion) might affect the viability of specific salmon species and initiated a formal consultation for these 37 with the NMFS.

The consultation process at the Services is overburdened, so NMFS did not act promptly. This delay resulted in another lawsuit, followed by a settlement requiring NMFS to issue the delayed BiOp. Following issuance of a draft BiOp and an opportunity for comment, a final BiOp was issued on November 18, 2008. The manufacturers of the three affected pesticides then brought the current case challenging the BiOp in District Court in Maryland.

The District Court originally agreed with NMFS that the BiOp would only be subject to judicial review in the context of subsequent reregistration actions by EPA, but the Fourth Circuit Court of Appeals reversed the District Court and held that the BiOp was indeed final action subject to review under the Administrative Procedure Act. The District Court then issued a decision on October 31, 2011, in which it granted summary judgment to the NMFS and affirmed EPA’s obligation to review its reregistration decision for the three pesticides in light of the BiOp.

The new decision by the Court of Appeals reverses the District Court once again. A key part of the new decision discusses the principle that review of agency action must be based on a contemporaneous rationale, and that post hoc rationalizations are not permitted. NMFS submitted a supplementary affidavit and provided additional explanation of the rationale for the BiOp in its brief, but the Court of Appeals states that it was an error for the District Court to consider this information. Because the BiOp was 482 pages in length, the Court observes that “it can hardly be argued that the administrative record was so lacking in explanations as to necessitate reliance on a litigation affidavit in conducting judicial review.”

In discussing the three specific issues where the explanation provided in the BiOp was deficient, the court notes that EPA itself criticized the 96-hour exposure assumption as well as the reliance on old monitoring data. The court also notes that the District Court itself “recognized that the BiOp was infirm in two critical respects,” due to inadequate explanation in the BiOp of the 96-hour exposure assumption and the recommendation for uniform buffers as mitigation. Based on the three specific deficiencies in the BiOp, the District Court is directed to remand the BiOp to NMFS for further analysis and revision.


This new decision will likely cause the Services to reevaluate the adequacy of scientific methodologies they use in preparing Biological Opinions, and will almost certainly change the level of explanation for key analytical assumptions that is considered to be sufficient. In turn, these changes can be expected to exacerbate a queuing problem with the ESA consultations for pesticides that EPA has already initiated or committed to consider initiating. Claims by the plaintiffs in Center for Biological Diversity v. EPA in the District Court in California (also referred to as the “Mega-ESA” case) that EPA improperly failed to consult concerning hundreds of pesticides would further overburden the Services, although EPA and industry groups have argued that that these claims are both untimely and improperly pleaded.

This new decision can also be expected to lead to further discussion of potential revisions to the existing process for commencing and completing consultation under the ESA, which many argue will become increasingly dysfunctional without some sort of legislative revision or reform. This decision could provide some renewed impetus to proposals for statutory changes, since the decision by itself does not remove the requirement for compliance with the current ESA. In addition, the anticipated release within weeks of the National Academy of Sciences’ report on the ESA assessment process for pesticides will further impact any debate about whether the law or current procedures should be changed. In the meantime, discussion within the affected agencies may focus not only on revisions to the procedures the Services use to prepare BiOps, but also on the preliminary screening methodologies that cause EPA to initiate so many consultations in the first place.