The U.S. District Court for the Southern District of West Virginia, Ohio Valley Envt’l v Elk Run Coal Co  Case No. 12-cv-0785, found liability for discharge to surface waters of ionic pollutants (measured by conductivity) that adversely affect stream macroinvertebrate communities.  The rationale expressed in this decision may have ramifications for the regulated community regarding which types of alleged permit violations may be subject to action by citizens suits and to what extent the courts may act as “super regulators” to impose obligations different from those imposed by the state agencies authorized to oversee the regulated activities.  Although the case orignates in Appalachian coal mining, the court’s evaluation of expert testimony relevant to  general and specific causation of harm, as determined by levels of conductivity and biotic index scores, may affect interpretations of alleged harm caused by pollutants in stormwater and other surface discharges.

Plaintiffs alleged violations of permits issued to the mining company defendants under the Clean Water Act and the Surface Mining Control and Reclamation Act.  The court found that plaintiffs had proved  that defendants had each committed at least one violation of their permits by

discharging . . . high levels of ionic pollution, which have caused or materially contributed to a significant adverse impact to the chemical and biological components of the applicable stream’s aquatic ecosystem, in violation of the narrative water quality standards that are incorporated into those permits.”

The court distinguished this case from that of Nat’l Mining Ass’n v. Jackson, 880 F. Supp. 2d 119 (D. D.C. 2012), in which the D.C. District Court invalidated conductivity limits that the US EPA sought to impose by guidance document.  In contrast, the court held in Elk Run Coal that EPA’s findings contained in “A Field-Based Aquatic Life Benchmark for Conductivity in Central Appalachian Streams” were scientific findings and, as such, the study was a scientific study within the agency’s area of expertise.

In its detailed, 67-page discussion the court (1) relied on plaintiffs’ expert testimony about the relationship of measures of conductivity and the West Virginia Stream Condition Index (WVSCI) scores; (2) rejected language in a guidance document from the WVDEP that concluded, among other findings, that there was no causative effect between high conductivity and low WVSCI scores; and (3) rejected application of West Virginia legislative actions concerning the relationship between narrative water quality criteria and the makeup of aquatic communities.