2023-10-23 North Kona Sewer Pump Station Section 106 Consult PL-CRC-2023-000011

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Overview of Undertaking The County ofHawai`i DEM is proposing to develop a North Kona Sewer Pump Station (SPS) within TMK: (3) 7-4-008:090(formerly 7-4-008:077 por. I) in Honokohau Ahupua`a. The North Kona SPS will consist of a below-grade pump station, above-grade operations, an emergency generator building, and a fuel storage tank. The North Kona SPS also includes the construction of two new sewer lines: a gravity line and a dual force main. The proposed pump station would be located makai(seaward) of the Mamalahoa Trail (State Inventory of Historic Places [SIHP] # 50-10-27-00002), and the above-grade operations building and fuel storage would be located mauka(inland,toward the mountains)of the trail,approximately 260 feet(ft) upslope of the pump station. Both portions of the facility will be connected by a 12-to 15-ft- wide access driveway crossing the Mamalahoa Trail. The below-grade pump station will be located just mauka from existing manholes to allow connection to sewer lines constructed by the State Department of Transportation along the Queen Ka`ahumanu Highway. Underground electrical and control lines and the potable water line will be placed below the access driveway. This configuration will minimize disturbance to the Mamalahoa Trail which lies between the two facilities. To avoid additional impacts to the Mamalahoa Trail during construction, a temporary access route extending from TMK: (3) 7-4-008:090 (formerly 077 por. 1)through TMKs: (3) 7-4- 008:077 and 078 is proposed. This temporary access route is within an existing planned easement for the Kanalani Street extension, which is part of the Lanihau subdivision. The temporary access corridor will extend approximately 265 m (870 ft) north of the pump station site, terminating at the northern boundary of TMK: (3) 7-4-008:078. The project also involves the installation of new sewer lines. One of the proposed lines is an 8- inch gravity line within the Hina LLani right-of-way (ROW) in TMK: (3) 7-3-009 in Kaloko Ahupua`a. This line ends at the mauka side of the Queen Ka`ahumanu Highway ROW. This line extends from the sewer system located within the County Homes of Ulu Wini affordable housing development project to an existing stub located on the mauka side of the Queen. Ka`ahumanu highway ROW. Additionally, new force main lines (8-to 20-inch diameter) are proposed within a landscaping easement at TMK: (3) 7-4-008:072 in Kealakehe Ahupua`a, paralleling the Queen Ka`ahumanu Highway between Kealakehe Parkway and the Kealakehe Wastewater Treatment Plant. These force mains will connect to the two 20-inch diameter lines already in the ground between Kealakehe Parkway and the pump station. Area of Potential Effect(APE) The North Kona SPS Project APE is approximately 13.25 acres (6.06 hectares). The APE, which is depicted on a 2022 aerial map(Attachment A), includes: ✓ The proposed 2.596-acre SPS site located within TMK: (3) 7-4-008:090 (formerly 7-4- 008:077 par. 1); • The temporary access route extending from TMK: (3) 7-4-008:090 (formerly 7-4-008:077 por. 1) through TMKs: (3) 7-4-008:077 and 078; 2