SRP submitted an ESA Analysis for a Low

- NO x Burner Project to EPA in April 2008 (revised July 2008). Based on the habitat conditions surrounding the Low

- NO x Burner project area, only one species from the Federal Coconino County threatened and endangered species list was expected to occur in the Pro ject vicinity: the California Condor ( Gymnogyps californianus ). No breeding or nesting sites were observed for this species in the Low

- NO x Burner Project area. The Low

- NO x Burner Project occurred within the boundaries of the active plant site, which is alr eady a developed industrial area, and it is expected that the one species identified in the analysis generally avoids human contact and thus avoids the facility area. In addition to the possible construction impacts on the listed species, SRP conducted a C O modeling analysis to determine the impact of CO emissions increases on the 1

- hour and 8

- hour average National Ambient Air Quality Standards (“NAAQS”). The modeling results showed that emissions increases of CO from the Project do not result in ambient co ncentrations that exceed the NAAQS, therefore, SRP concluded that a more detailed review would not be required for CO impacts on plants, soils, and animals. However, the modeling analysis showed that impacts of CO from the Low

- NOx burner project exceed the Significant Impact Limits (“SILs”) at least 8 kilometers from the facility boundary. EPA reviewed the analysis submitted by SRP and found that the Low

- NO x burner Project may affect, but is not likely to adversely affect the California Condor or its critic al habitat, in accordance with 50 C.F.R. §§ 402.13 and 402.14(b). FWS replied in concurrence with th is finding on November 13, 2008

. Since 2008, two additional species have been added to the Federal Coconino County threatened and endangered species list: the Northern Mexican Garter Snake ( Thamnophis eques megalops ) and the Narrow

- headed Garter Snake ( Thamnophis rufipunctatus ). Both of these species are strongly dependent on aquatic and riparian habitats

. Several species included in the species list for the 2008 Low

- NOx Burner Project, including the Razorback sucker ( Xyrauchen

texanus ) and the Yellow

- billed Cuckoo ( Coccyzus americanus ), are known to occupy areas with similar habitats to the Northern Mexican Garter Snake and Narrow

- headed Garter Snake. As with other species dependent on the presence of aquatic or riparian habitat, both the Northern Mexican Garter Snake and Narrow

- headed Garter Snake are unlikely to be found within the vicinity of the R CTS Project area because of the lack of suitable habitat

. Conference with the FWS has confirmed that these species are not likely to be found near the NGS. The California Condor remains the only species listed on the Federal Coconino County threatened and endangered species list which is expected to occur in th e vicinity of the R CTS Project area at the NGS.

SRP conducted a PM 10 and PM 2.5 modeling analysis for the R CTS Project to determine the impact of emissions increases on the annual and 24

- hour PM 10 and PM 2.5 National Ambient Air Quality Standards (“NAAQS”). The modeling showed that maximum concentrations of PM 10 and PM 2.5 occur at the facility boundary and that increases of these pollutants of do not exceed the SILs outside the existing facility boundary and do not result in ambient concentrations that exceed any applicable NAAQS

. Therefore, SRP determined that a more detailed review would not be required to analyze the impacts of PM 10 and PM 2.5 on plants, soils and animals. EPA has reviewed the application and modeling report for the RCTS Project and has concluded that the increase in emissions will not affect the California Condor because emissions from the Project extend ing beyond the existing facility boundary are insignificant.

On November 20, 2015, EPA sought concurrence from the FWS in the form of a letter for its finding that the RCTS Project may affect, but is not likely to adversely affect, anyfederally

- listed endangered or threatened species or designated critical habitat for such species. Subsequent discussion with the FWS indicated that they believe that no endangered or threatened species or critical habitat will be affected by the RCTS Project, nor is it likely to jeopardize the continued existence of a ny proposed species or adversely modify any proposed critical habitat. FWS followed by stating in a letter to EPA dated December 18, 2015 that no further review is required for the RCTS Project. Therefore, it is EPA ’ s determination that the Tribal NSR minor modification will have no effect on endangered or threatened species in the area, and further action with the FWS is not necessary in accordance with 50 CFR 402.13

.