Kapulena Hamakua EA PBR Final TMK No. 4-7-005 and 006

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KAPULENA AGRICULTURAL PARK FINAL ENVIRONMENTAL ASSESSMENT 3.4 SOILS Three soil suitability studies have been prepared for lands in Hawaii. These are the U.S. Department of Agriculture Soil Conservation Service Soil Survey (USDA 1972), the University of Hawaii Land Study Bureau Detailed Land Classification (Baker 1965), and the State of Hawaii Department of Agriculture's Agricultural Lands of Importance to the State of Hawai `i (ALISH) (State of Hawaii 1977). The principal focus of these studies has been to describe the physical attributes of Hawai`i's lands and the relative productivity of different land types for agricultural production purposes. 3.4.1 Soil Conservation Service Soil Survey The Soil Survey of the Island of Hawai `i, State of Hawai `i (USDA 1972) identifies the following eight soil types at the Kapulena Lands (Figure 8, Soils). • Honokaa Silty Clay Loam, Low Elevation, HsD (10 -20% slopes) • Honokaa Silty Clay Loam, Low Elevation, HsE (20 -35% slopes) • Honokaa Silty Clay Loam, HTD (10 -20% slopes) • Kukaiau Silty Clay Loam, KuD (12 -20% slopes) • Kukaiau Silty Clay Loam, KuE (20 -35% slopes) • Paauhau Silty Clay Loam, PaD (12 -20% slopes) • Paauhau Silty Clay Loam, PaE (20 -35% slopes) • Rough Broken Land, RB Honokaa Silty Clay Loam, 10 -20% slopes (HTD) constitutes approximately 345 acres, or roughly 20 percent of the Kapulena Lands, and is located at the site's highest elevations. In a representative profile, the surface layer is dark brown silty clay loam, approximately 6 inches thick. The subsoil is also silty clay loam. It is dark brown, very dark brown, and very dark grayish brown and is approximately 59 inches thick. This soil is medium acid to slightly acid throughout the profile. It dehydrates irreversibly into fine gravel -size aggregates. Permeability is rapid, runoff is slow, and the erosion hazard is slight. Roots can penetrate to a depth of 5 feet or more. This soil is used mostly for pasture and woodland. At the time of the survey (1972), a small acreage at the lowest elevation was used for sugarcane. These soils are in capability Class IV. Honokaa Silty Clay Loam, Low Elevation, 10-20% slopes (HsD) constitutes approximately 28 acres or roughly 1.6 percent of the Kapulena Lands. This soil is similar to Honokaa silty clay loam 10 to 20 percent slopes, except that it occurs at a lower elevation where the soil temperature is warmer. This soil was historically used mainly for sugarcane. Small areas are used for pasture and macadamia nuts. These soils are in Capability Class IV. Honokaa Silty Clay Loam, slopes Low Elevation, 20-35% (HsE) constitutes approximately 255 acres or roughly 15 percent of the Kapulena Lands. A band of this soil type runs the length of the site between the 1600 foot and 1700 ground elevation level. This soil is similar to Honokaa silty clay loam 10 to 20 percent slopes, except that it is steep and occurs at a lower I