alternatives to decision makers and the public. Activities associated with each alternative are assessed as either beneficial, minor adverse, moderate adverse, or major adverse for short-term, long-term, and cumulative impacts according to intensity definitions specific for each resource topic. Beneficial is defined as “a positive change in the condition or appearance of the resource or a change that moves the resource toward a desired condition,” while adverse is defined as “a change that moves the resource away from a desired condition or detracts from its appearance or condition.”2 It is noteworthy that only one category of beneficial impact is used, hence effects that may range from minor to major beneficial cannot be distinguished. In addition, the impact intensities do not allow for a finding of negligible impact, a category that is included in NPS NEPA guidance documents, “Summary of Regulations and Policies — Impact Indicators and Criteria,” Director’s Order 12.3 A complete list of the impact definitions from the DEIS for each of the resource categories is provided in Appendix C.
For each resource category, the committee (1) examined the interpretations, analyses, and conclusions given in the DEIS; (2) assessed the extent to which they are reasonable and scientifically sound based on information in the DEIS; (3) based on this evaluation, assessed the level of uncertainty associated with the impact intensity conclusions in the DEIS and, where appropriate, offered possible alternative conclusions that are equally reasonable and scientifically sound; and (4) determined if there is additional information and analyses that are not in the DEIS but that could be used to reduce levels of uncertainty.
The committee addressed the resource categories as they were presented in the DEIS, with an exception for a separate discussion on non-indigenous species. As was often indicated by cross-referencing in the DEIS, there are no clear boundaries between resource categories. The assessment of an impact on one resource may depend in part on the predicted effect to another resource. This is the nature of ecosystems, which are characterized by complex interactions among and between living and non-living components.
I. QUALITY OF INFORMATION AND ANALYSIS AND INFORMATION GAPS
The DEIS provides a qualitative inventory of wetlands in Drakes Estero and presents GIS maps of the distribution of the different types of wetlands. The focus of the DEIS is on the wetland area located between the mean low tide elevation and 100 ft landward of the high tide line.4 These areas are characterized by mostly unvegetated substrates5 among which mudflats dominate.6 Inclusion of the unvegetated substrates is prompted by the DEIS integrated application of both the Environmental Protection Agency (EPA)/U.S. Army Corps of Engineers (USACE) and U.S. Fish and Wildlife Service (USFWS) definitions of ‘wetlands.’ However, it is evident from the DEIS and from NPS statements at the committee’s 11 July 2012 public meeting that some tidal-freshwater wetlands were excluded7 even if they fit the operational definition of “100 ft landward of the high tide line” (assuming that the high tide line is correctly interpreted). Onshore wetland areas are also discussed in the section on Special-Status Species.
The DEIS lists three DBOC activities that could impact wetlands under alternatives B, C, and D: continued use and maintenance of shellfish racks and bags in Drakes Estero; continued boat traffic; and installation of a new dock, including dredging. For alternative D, the DEIS adds potential impacts from increased production level, new onshore development, and placement of a new intake pipeline.
The wetland area currently permitted for culture bags (Table 2.1) will not change greatly under alternatives B, C, or D. However, the balance between bag and rack culture could change under alternatives B, C, and D and may vary from year-to-year as discussed in Chapter 2. The most important potential impacts on intertidal mud and sand flats are related to motor boat traffic; workers walking across the flats to place, turn and recover culture bags; and the number and placement of bags themselves. These activities may have a direct impact on turbidity, sediment dynamics, benthic fauna, harbor seals,
2 DEIS, p. 235.
4 DEIS, p. 166.
5 DEIS, p. 166.
6 DEIS, p. 249.
7 DEIS, Table 3-1 and Figures 3-1 and 3-2.