Key Holdings NEPA Health Impacts of NAAQS Pollutants. The plaintiffs argued that the EIS should have analyzed the human health impacts of NAAQS pollutants. The court ruled that FHWA likely permissibly relied on NAAQS compliance as a proxy for determining that emissions of NAAQS pollutants would not significantly affect human health. The court reasoned that NAAQS are set at a level necessary to protect human health with an adequate margin of safety; thus, if the project’s emissions would not cause NAAQS to be exceeded, it would not impact human health. The court cited numerous other cases that reached the same conclusion for transportation projects. The court also noted that the plaintiffs did not articulate a clear and manageable standard for determining when NEPA requires investigation of air pollutant health impacts even if an action will not exceed NAAQS levels. The plaintiffs relied on a study by the Denver Department of Environmental Health that they claimed indicated public health disparities in parts of the city located near I-70, but the court determined that the study was not empirically rigorous and did not indicate that proximity to I-70 caused adverse health impacts in nearby communities. Health Impacts of MSATs. The plaintiffs argued that FHWA should have evaluated specific health effects from MSATs, for which there are no NAAQS. The court held that the plaintiffs were unlikely to succeed on this argument. The court explained that all alternatives in the FEIS, including the no-action alternative, would have significantly less MSAT emissions than current levels. Moreover, because all alternatives would have substantially the same MSAT emissions, FHWA’s decisionmaking would not be materially enhanced by additional analysis of health effects. The court noted that the plaintiffs appeared to be arguing that the agencies should have evaluated relative health benefits of the alternatives that were eliminated at the SDEIS phase, but the court explained that the agencies had no obligation to analyze alternatives that it has already rejected in good faith. Federal-Aid Highways Act. The plaintiffs argued that Section 109(h) of the Federal-Aid Highways Act required the agencies to prepare additional health impact analyses. The court noted that FHWA’s NEPA-implementing regulations are intended to satisfy the agency’s obligations under Section 109(h) in a single environmental review document. The court held that Section 109(h) did not create additional substantive requirements apart from FHWA’s NEPA process, and that FHWA’s compliance with its NEPA regulations could satisfy its obligations under Section109(h). Preliminary Injunction The court concluded that the plaintiffs were not likely to succeed on the merits of their claims, and, therefore, denied their request for a preliminary injunction. Administrative Record The court denied the plaintiffs’ request to add various documents to the administrative record, but allowed the plaintiffs to conduct limited discovery regarding FHWA’s PM10 modeling methodology. Expert Declarations and Reports. The plaintiffs sought to supplement the record with five expert declarations and reports that asserted (1) compliance with NAAQS would not ensure protection against public health effects, (2) FHWA’s hot-spot analysis for estimating PM10 emissions was flawed, (3) PM2.5 emissions would likely exceed NAAQS if FHWA had used the same methodology to measure PM2.5 as it used for PM10, (4) a health impact assessment would be feasible and beneficial for the PCL Alternative, and (5) PM10 emissions would likely exceed NAAQS if FHWA had used EPA guidance for analyzing fugitive dust emissions. The court determined that all of these documents indicated disagreement with FHWA’s methodology, and did not demonstrate that FHWA entirely failed to consider human health or another relevant factor. The court explained that expert disagreement regarding an agency’s methodology is an insufficient basis for admitting extra-record evidence. Thus, the court denied the plaintiffs’ request to supplement the administrative record with expert declarations and reports. Summaries of Published Articles. The plaintiffs sought to supplement the record with a summary of nine published peer-reviewed articles related to assessing health impacts from highway emissions. The court denied the plaintiffs’ request because the articles were not specifically related to the project and the information about highway emissions in general did not demonstrate that FHWA failed to consider health effects. In addition, three articles were published after FHWA issued the ROD; including those articles would impermissibly add post-decision information to the record. Meeting Notes. The court denied the plaintiffs’ request to supplement the administrative record with notes from a meeting between the plaintiffs and FHWA. The notes indicated that the plaintiffs presented FHWA with studies regarding potential health effects of the PCL Alternative, which they argued demonstrated that FHWA did not consider health impacts. The court disagreed, because FHWA had discussed those studies in the FEIS. The court noted that the plaintiffs could still argue that FHWA did not adequately discuss and analyze those studies. Response to Open Records Request. The court denied the plaintiffs’ request to supplement the record with CDOT’s response to an open records request. The court explained that any admissions in the response to the open records request would be duplicative of information already in the record. Discovery Regarding Modeling Decisions. The court allowed the plaintiffs to conduct limited discovery related to FHWA’s decision to separately model PM10 concentrations at seven receptor locations. The ROD explained that FHWA used a more refined methodology than its original analysis in the FEIS to account for the true release height of emissions. The plaintiffs argued that discovery could provide information regarding how and why FHWA adjusted its model. The court allowed the plaintiff to serve five interrogatories on FHWA and/or CDOT related to this modeling decision, and required FHWA to produce all non-privileged documents on this topic. Documents on FHWA’s Website. The court denied the plaintiffs’ request to add five documents from FHWA’s website to the administrative record. The court held that the plaintiffs did demonstrate that those documents were presented to or considered by FHWA. The court explained that the documents’ mere existence on FHWA’s website did not indicate that FHWA directly or indirectly considered the documents in its decision. The court also denied the plaintiffs’ request to supplement the record with those documents because they did not indicate that FHWA failed to consider a relevant factor.