Final Comprehensive Conservation Plan - U.S. Fish and Wildlife ...

Hakalau Forest National Wildlife Refuge
Comprehensive Conservation Plan
3.4.1 Hakalau Forest Unit Topography
The relatively young Mauna Kea volcano does not contain deep valleys and high cliffs that are
distinctive on other volcanoes. As a result, the topography at the HFU is relatively gentle. The lower
elevation areas have deeper gulches and steeper slopes than higher elevation portions. The prevailing
aspect of the slopes is east. Cinder cones, built by lava fountains or erupting magma foam, are
scattered throughout the area (Stearns 1966, USFWS 1996b).
3.4.2 Kona Forest Unit Topography
The rectangular-shaped KFU slopes toward the west-southwest. The entire area has an average slope
of 20 percent, with slopes of less than 10 percent at the upper elevations (USFWS 2002b). The
surface of the entire parcel is rocky, irregular, and undulating (USFWS 2008a). Lava tubes and
shallow gulches also dissect the overlapping ‘a‘ā and pāhoehoe lava flows, creating uneven
topography (Rayond and Valentine 2007).
3.5 Environmental Contaminants
The Agency for Toxic Substances and Disease Registry, a Federal bureau of the U.S. Department of
Health and Human Services, defines a contaminant as “a substance that is either present in an
environment where it does not belong or is present at levels that might cause harmful (adverse)
health effects” (ATSDR 2002). Contaminants commonly include pesticides and their residues,
industrial chemicals, fertilizers, metals, and other toxic substances. By altering biological or physical
processes, contaminants may produce adverse and even detrimental effects to an ecosystem (USFWS
2005a).
No contaminated sites have been identified on the Refuge units (USFWS 2007). However, Hawai‘i
Island is exposed to high sulfur dioxide (SO2) levels from Kīlauea volcano emissions (vog), as well
as traces of metals such as mercury. Sulfur dioxide is an irritant gas that may cause acute and chronic
changes in human health, such as eye and respiratory system irritation (Michaud et al. 2005).
The National Priorities List (NPL), compiled under authority of the Comprehensive Environmental
Response, Compensation, and Liability Act of 1980 (United States Code, Title 42, Chapter 103),
provides an inventory of the Nation’s most contaminated hazardous waste sites. No sites are
identified on the island.
3.5.1 Hakalau Forest Unit Contaminants
Level I Environmental Site Assessment was conducted on the property prior to acquisition
(Woodward, pers. comm.). Potential on- and off-site contamination sources that have been identified
on or adjacent to the HFU include accidents and spills, agricultural livestock, forestry silviculture,
pesticide application, and recreation (USFWS, unpubl.).
3-12 Chapter 3. Physical Environment