Chapters 1 - U.S. Fish and Wildlife Service

Environmental Consequences
emissions is not however intended to be an indicator of a threshold of significant direct or indirect
effects. Further, CEQ does not propose to make this guidance applicable to Federal land and
resource management actions and is instead seeking public comment on the appropriate means for
assessing the GHG emissions of Federal land and resource management decisions.
At the state level, various options are being considered for setting a threshold for GHG emissions
in California including zero and non-zero levels, while another option involves addressing project
effects without establishing a threshold. The latter could be accomplished through a quantitative
or qualitative evaluation of individual projects.
Activities that would occur on the Refuge under Alternative A that would emit GHGs include the
use of vehicles by staff and volunteers to get to and from the Refuge, the use of vehicles by visitors
to the Refuge, the use of motorized equipment to implement management actions, the occasional
use of trucks to provide supplies to the Refuge, and the use of electricity for power and heat within
the Refuge office. Quantifying the amount of GHG emissions generated from these types of uses is
difficult; however, through the use of the USEPA’s Greenhouse Gas Equivalencies Calculator
(USEPA 2009), it is possible to get a general idea of the magnitude of the emission associated with
such uses. To obtain an estimate the number of metric tons of CO 2 emissions that could be
generated annually as a result of implementing Alternative A, we estimated the number of miles
traveled by Refuge staff, visitors, and volunteers to get to and from the Refuge on an annual basis
and then translated in gallons of gasoline consumed per year as a result of this travel. Based on
data provided by the USEPA Calculator, approximately 42 metric tons of CO 2 emissions would be
generated annually as a result of these trips. The operation of the Refuge Office/Visitor Contact
Station requires approximately 14 kilowatt hours per month (168 kilowatt hours per year), which
represents about 0.12 metric tons of CO 2 emissions per year (USEPA 2009). Based on these
calculations, Alternative A would be expected to generate annual GHG emissions generally
equivalent to the annual GHG emissions generated by eight passenger vehicles.
Another aspect of Alternative A is the proposal to protect and manage native habitats on the
Refuge. The majority of the Refuge supports salt marsh habitat, which is considered very effective
in removing carbon from the atmosphere and storing it in marsh soils (Chmura, et al. 2003).
Further, unlike freshwater marshes, tidal salt marshes release only negligible amounts of
methane, a powerful greenhouse gas, so the overall benefits of carbon sequestration provided by
salt marsh are great (Brevik and Homburg 2004).
In the absence of more specific guidance on how to determine a level of significance, we have
compared the level of GHG emissions from this proposal to other types of GHG emission
generators, as well as considered the carbon sequestration benefits of the salt marsh habitat
present on the Refuge. Based on these factors, we have concluded that given the very low levels of
GHG emissions that would result from the implementation of Alternative A, the GHG emissions
from this project do not represent a significant direct or indirect impact on the environment.
5.2.1.10 Effects Related to Contaminants
Wildlife and Habitat Management
Under Alternative A, the primary ground disturbing activity that would continue to occur on the
Refuge is the planting of native vegetation following invasive plant species control. This activity
generally occurs in upland areas around the eastern perimeter of 7 th Street Pond, on the outer
edges of Hog Island, and other disturbed upland areas on the perimeter of the Refuge. Areas
identified by the Navy through their Installation Restoration program that could contain
Draft Comprehensive Conservation Plan 5-11