Opinion ID: 796659
Heading Depth: 4
Heading Rank: 4

Heading: Performance Standards Expressed as Ranges

Text: 70 The Phase II Rule establishes performance standards expressed as an 80 to 95 percent reduction in impingement mortality and a 60 to 90 percent reduction in entrainment, which existing power plants must achieve, subject to certain exceptions, in order to be considered in compliance with the Rule. 40 C.F.R. § 125.94(b)(1), (2). The environmental petitioners challenge the Rule's wide and indeterminate ranges as failing to constitute precise single-level limitations based on the best technology available for minimizing adverse environmental impact and argue that these ranges are inconsistent with Congress's intent that there be a national standard under section 316(b). We agree in part and, because the EPA in reconsidering its selection of BTA on remand may alter the suite of technologies it originally selected, thereby causing a coordinate alteration in the performance ranges, we provide some guidance to the EPA insofar as the petitioners' challenge touches on the limits of the Agency's authority. Although the EPA may, in the circumstances to be discussed, set performance standards as ranges, it must require facilities to minimize the adverse environmental impacts attributable to their cooling water intake structures to the best degree they can. 71 The petitioners note that the EPA has found that certain screens and filter systems can reduce impingement mortality by up to 99 percent and that similar technologies can produce 80 to 90 percent reduction in entrainment. 69 Fed.Reg. at 41,599. They contend that the CWA therefore requires the EPA to set BTA standards reflecting these best performers, see Texas Oil & Gas Ass'n v. EPA, 161 F.3d 923, 928 (5th Cir.1998) (Congress intended these [BAT] limitations to be based on the performance of the single best-performing plant in an industrial field. (citation and internal quotation marks omitted)), particularly given the EPA's acknowledgment that [t]he higher end of the range is a percent reduction that available data show many facilities can and have achieved with the available technologies upon which the performance standards are based. 69 Fed.Reg. at 41,600. The petitioners emphasize that the Rule's ranges impermissibly fail to require facilities even to attempt to achieve performance equal to the upper bound of the prescribed ranges. 72 According to the EPA, section 316(b) does not require a single-numeric standard applicable to all Phase II existing facilities, and expressing the performance standards as ranges is necessary to account for the variables involved in reducing impingement mortality and entrainment under local conditions at particular facilities. The EPA contends that [b]ecause the Phase II requirements are applied in a variety of settings and to existing facilities of different types and sizes, no single technology is most effective for all facilities subject to the Rule. The Agency argues that the technologies do not provide a fixed level of performance at all facilities and that their performance is affected by the nature of the waterbody, facility intake requirements, climatic conditions, and the waterbody's biology. The EPA argues also that the permit process requires facilities to reduce impingement mortality and entrainment commensurate with the efficacy of the installed technologies, which it claims ensures that the installed technologies will be maintained to ensure their utmost efficacy. 19 The difficulty with the EPA's arguments is that the Rule does not require facilities to choose technologies that produce the greatest reduction possible. 73 Our decision in Riverkeeper I sheds some light on the parties' arguments. In that case, we discussed the differences between the two tracks in the Phase I Rule: Track I set forth precise velocity and capacity requirements while Track II permitted compliance via technologies that would achieve at least 90 percent of the reduction in impingement mortality and entrainment that compliance with Track I would yield. See 358 F.3d at 182-83. The petitioners in that case challenged the Track II provision on the ground that it deviated from the statutory requirement that the EPA establish a single level of performance applicable to all facilities. Id. at 187. The EPA argued that Tracks I and II reflected the same standard and that 10 percent is an acceptable margin of error given that measurements of reduction of impingement mortality and entrainment are necessarily inexact and depend upon natural fluctuations in animal populations and sampling errors. Id. at 188. In assessing the parties' arguments, we stated that the EPA, consistent with Congress's intention that there be a national standard governing the discharge of pollutants, must promulgate precise effluent limitations under sections 301 and 306.... Id. (emphasis added). We went on to note, however, that while pollutant concentration and the velocity and volume of water withdrawn can be measured accurately, impingement mortality and entrainment cannot always be measured directly and with mathematical precision. Id. at 189. We concluded that the EPA acted reasonably in specifying how much ambiguity it is willing to tolerate in measuring compliance and what it considers a reasonable margin of error in comparing the performance of different technologies. Id. In short, we acknowledged that the Track II performance requirements, unlike the Track I requirements, could not be measured precisely and that it was therefore reasonable to consider a margin of error in comparing performance under the two standards. 74 This case is not entirely similar to Riverkeeper I because of the rationales that animate the EPA's creation of the performance ranges in Phases I and II. The Phase II Rule generally require facilities to reduce impingement mortality and entrainment by the specified percent ranges from the calculation baseline. 40 C.F.R. § 125.94(b). These ranges, as explained by the EPA, are based on the reductions achievable by using various technologies. See 69 Fed.Reg. at 41,599. The EPA explained that it expressed the performance standards in the form of ranges rather than a single performance benchmark because of the uncertainty inherent in predicting the efficacy of any one of these technologies. Id. at 41,600. It stated further that the lower end of the range is the percent reduction it expects all facilities could eventually achieve if they were to implement and optimize available design and construction technologies and operational measures on which the performance standards are based and that the higher end of the range is a percent reduction that available data show many facilities can and have achieved with the available technologies upon which the performance standards are based. Id. Unlike Riverkeeper I, therefore, a margin of error from a relatively precise benchmark that is tolerable given measurement difficulties is not at issue here. Instead, the performance standards reflect the range of performance associated with various technologies identified as BTA. That performance, in turn, depends in part on local conditions and natural fluctuations. Id. 75 Record evidence supports the EPA's conclusion that the percent reduction of impingement mortality and entrainment is not completely within the control of a facility and therefore may not be precisely achieved by a facility. See TDD for the Final § 316(b) Phase II Existing Facilities Rule 4-3. Reducing these adverse environmental impacts is not as easily measured and controlled as are the discharge of pollutants and the capacity and flow rate of water intake. 20 We therefore acknowledge that in many cases it may be difficult, as a practical matter, for the EPA or other permitting authority to predict which plants will be able to achieve the upper, as opposed to the lower, end of the ranges. This uncertainty, however, does not justify a rule that permits even those facilities that could achieve the upper end of a range to be deemed in compliance if they reach only the lower end, particularly when the EPA has acknowledged that many facilities can and have achieved reductions at the high end of the range. 69 Fed.Reg. at 41,600. Congress's use of the superlative best in the statute cannot be read to mean that a facility that achieves the lower end of the ranges, but could do better, has complied with the law. The statutory directive requiring facilities to adopt the best technology cannot be construed to permit a facility to take measures that produce second-best results, see Chevron, 467 U.S. at 843, 104 S.Ct. 2778, especially given the technology-forcing imperative behind the Act, Natural Res. Def. Council, 822 F.2d at 123. Insofar as the EPA establishes performance standards instead of requiring facilities to adopt particular technologies, it must require facilities to choose the technology that permits them to achieve as much reduction of adverse environmental impacts as is technologically possible. 21 For this reason, the EPA on remand should address these concerns if in its BTA determination, it retains performance ranges.