Hawaii-Southern California training and testing activities, final Environmental Impact Statement/Overseas Environmental Impact Statement

The United States Department of the Navy (Navy) prepared this Environmental Impact Statement (EIS)/Overseas EIS (OEIS) to comply with the National Environmental Policy Act (NEPA) and Executive Order 12114. This EIS/OEIS evaluates the potential environmental impacts of conducting training and testing activities after December 2018 in the Hawaii-Southern California Training and Testing Study Area (Study Area). The Study Area is made up of air and sea space off Southern California, around the Hawaiian Islands, and the transit corridor connecting them. Three alternatives were analyzed in this EIS/OEIS:  The No Action Alternative would be no training and testing activities associated with the Proposed Action within the Study Area.  Alternative 1 (Preferred Alternative) reflects a representative year of training and testing to account for the natural fluctuation of training and testing cycles and deployment schedules that generally limit the maximum level of activities from occurring year after year in any 5-year period. Using a representative level of activities rather than maximum level reduces the amount of ship hull-mounted, mid-frequency active sonar estimated to meet requirements. Under Alternative 1, the Navy assumes that some unit-level training and testing would be conducted using synthetic means (e.g., simulators). Additionally, this alternative assumes that some unit-level active sonar training will be completed through other training exercises.  Under Alternative 2, the Navy would be enabled to meet the highest levels of required military readiness in order to respond to naval opponents. Alternative 2 reflects the maximum number of training and testing activities that could occur within a given year and assumes that the maximum level of activity would occur every year over a 5-year period. This allows for the greatest flexibility for the Navy to maintain readiness when considering potential changes in the national security environment, fluctuations in schedules, and anticipated in-theater demands. The resources evaluated include air quality, sediments and water quality, vegetation, invertebrates, habitats, fishes, marine mammals, reptiles, birds, cultural resources, socioeconomic resources, and public health and safety. Prepared by: United States Department of the Navy Point of Contact: HSTT EIS/OEIS Project Manager Naval Facilities Engineering Command, Pacific/EV21 258 Makalapa Dr., Suite 100 Pearl Harbor, HI 96860-3134 Hawaii-Southern California Training and Testing Final EIS/OEIS October 2018 F-i Foreword FOREWORD The Draft Hawaii-Southern California Training and Testing (HSTT) Environmental Impact Statement/Overseas Environmental Impact Statement (EIS/OEIS) was released for public review and comment 13 October 2017 through 12 December 2017. Changes in this Final EIS/OEIS reflect responses to all substantive comments made on the Draft EIS/OEIS during the public comment period as well as Navy refinements to the Proposed Action. Public comments are summarized, and their corresponding responses are provided in Appendix H, Public Comments and Responses. While most sections in the EIS/OEIS were changed in some manner between the draft and final versions, many of those changes entailed minor modifications to improve clarity. The key changes between the HSTT Draft EIS/OEIS and Final EIS/OEIS follow.  Chapter 1 (Purpose and Need): The description of the Purpose and Need was revised to explain that this EIS/OEIS was prepared to meet both the Navy’s and the National Marine Fisheries Service’s respective National Environmental Policy Act (NEPA) obligations and support the decisionmaking of both agencies.  Chapter 2 (Description of Proposed Action and Alternatives): The description of the Hawaii Range Complex was revised to clarify and distinguish the Temporary Operating Area and the Hawaii Operating Area. The description of the Southern California portion of the HSTT Study Area was revised to better explain the components that make up the Study Area. All changes were to the descriptions only; no changes were made to the actual Study Area. Descriptions of some proposed training and testing activities were revised to more definitively describe the activity. The activities themselves did not change and did not require new analyses. The analyses conducted for the Draft EIS/OEIS remain valid for the Final EIS/OEIS. Descriptions of some standard operating procedures were revised to illustrate how the procedures provide benefits to environmental and cultural resources. The Navy added in the Final EIS/OEIS that it considered but eliminated an alternative based solely on geographic mitigation. The frequency of one training activity was decreased from the Draft to the Final EIS/OEIS: the Mine Neutralization Explosive Ordnance Disposal activity conducted in the Southern California Range Complex was reduced from 194 events per year and 970 over 5 years, to 170 per year and 850 over 5 years. Because the number of explosives used did not change, the analysis as described in the Draft EIS/OEIS remains valid.  Section 3.0 (Introduction to Affected Environment and Environmental Consequences): In the Final EIS/OEIS, the Navy included additional detail about data sources utilized in the Marine Species Density Database, and added a description of the Navy’s Acoustic Effects Hawaii-Southern California Training and Testing Final EIS/OEIS October 2018 F-ii Foreword Model used to estimate the number of marine mammals or sea turtles that could be affected by Navy sonar and explosives. The number of testing air gun sources in Table 3.0-3 in the Draft EIS/OEIS did not reflect the number of sources that were analyzed. Table 3.0-3 in the Final EIS/OEIS shows the correct number of air gun sources that were quantitatively analyzed in both the Draft EIS/OEIS and the Final EIS/OEIS, 844 per year, 4,220 over 5 years. The description of how vessel noise was analyzed was revised, and various tables and figures were updated. Various tables were updated to reflect a more accurate accounting of quantities of military expended materials and other non-acoustic and explosive stressors associated with proposed training and testing activities. The changes, which included increases and decreases, were considered in the Final EIS/OEIS analysis, but did not result in changes to the conclusions reached in the Draft EIS/OEIS. The description of fiber optic cables expended during training and testing activities was revised with more recent information. The description of decelerators/parachutes was revised to reclassify the various sizes of decelerators/parachutes proposed for use. The new decelerator/parachute size classification was carried throughout all the resource sections for analysis.  Section 3.1 (Air Quality): Additional information regarding attainment, National Ambient Air Quality Standards, and the General Conformity Evaluation was added in the Final EIS/OEIS. The Navy added a description of two islands that occur in the Study Area, but are included in the South Central Coast Air Basin. In the Final EIS/OEIS, the emissions tables were revised to present the data in an overall summary format, and comparisons to the baseline emissions were provided. The Prevention of Significant Deterioration Thresholds were updated in all applicable tables. Some emissions estimates were revised to correct minor calculation errors. All revisions were minor, and no conclusions were affected. The Record of Non-Applicability was signed by the Navy and included in Appendix C.  Section 3.2 (Sediments and Water Quality): Changes were made to the description of sediment class sizes in the Affected Environment section to be consistent with a single, modern classification system. Minor adjustments to all map figures were made to ensure the figures are consistent in labeling and nomenclature with other sections in the Final EIS/OEIS. The Navy added clarification that some anchors used to moor seafloor devices may be left on the seafloor after the seafloor devices are recovered.  Section 3.3 (Vegetation): A description of procedural mitigation measures was added to explain how those measures could benefit vegetation. The Essential Fish Habitat Determinations section was removed Hawaii-Southern California Training and Testing Final EIS/OEIS October 2018 F-iii Foreword from this section, with a complete summary provided in Chapter 6 (Regulatory Considerations).  Section 3.4 (Marine Invertebrates): The General Background section was updated to include additional information on habitat use, movement and behavior, and climate change. Additional information was also added in the description of corals. The description of impacts from sound sources was revised with information from recent studies. No conclusions changed as a result of the new information. The Essential Fish Habitat Determinations section was removed from this section, with a complete summary provided in Chapter 6 (Regulatory Considerations).  Section 3.5 (Marine Habitats): Figures depicting the bottom substrate compositions and artificial structures within the Study Area were updated. The analysis of impacts was revised to provide updated areas potentially affected by explosives or military expended materials, and a description of mitigation measures was provided, explaining how the measures could benefit important habitats from these activities. Impact footprint estimates were revised as calculation errors were discovered. All revisions were minor, and no conclusions were affected. Additionally, the habitats database was updated to include recently published data sources including both mapped polygon and point data. The Essential Fish Habitat Determinations section was removed from this section, with a complete summary provided in Chapter 6 (Regulatory Considerations).  Section 3.6 (Fishes): The General Background section was updated in several places with new information that wasn’t available when the Dr