The proposed project is intended to use renewable, non-polluting solar energy devices to sell power to the public utility. The following summary of potential effects is based on available information, including publicly available environmental databases. Where possible, identifiable existing conditions are provided and the short- and long-term direct, indirect, and cumulative impacts likely to result from the development, operation, and decommissioning of the project.
The project site is located on the southern side of Hawaii, in Pahoa/Nāʻālehu. Access to the site is off Waiohinu Spur Road which is an unimproved road.
Air quality -
Temporary air quality may be impacted during construction through the generation of fugitive dust while grubbing and grading. The short time between original clearing, not disturbing more than necessary, and placement of ground cover will minimize and limit impacts. Mitigation measures during construction may include watering, application, soil cement products, and erection of dust fences.
Operation of the proposed facility does not result in emissions that have the ability to affect air quality and thus will have no negative effect on ambient air quality.
Biological Resources – no site flora or fauna surveys or reconnaissance was performed specifically to flora and fauna. The site has been vacant land for several decades and contains a mix of sparse grass and shrublands vegetation. A biological survey will be conducted during development to identify any potential flora or fauna resources requiring mitigation. No native Hawaiian plants are known at this time nor the presence of listed rare or endangered species. No significant adverse impacts are anticipated as a result of clearing or grubbing activities or site operations.
Climate – There are normally two seasons, summer and winter. Summer tends to be warm, muggy, windy, and partly cloudy, while winter is wetter and cooler. Winds vary throughout the year, and it is mostly clear year-round. Temperatures range between a low of 62 degrees F and 84 degrees F. The dry season lasts about 5 months from April to November while the wet season lasts almost 7 months from November to April. Monthly rainfall averages between 1.3 inches and 4.8 inches.
Soils – According to the U.S. Department of Agricultural Soil Conservation Service, Web Soil Survey, the soil type for the site consists of Kanohina-lava flows complex with 2 to 10 percent slopes. The soil type appears well suited for facility construction and will not create a loss of land or risk of erosion.
Topography – the project is located on generally flat land to the slightly sloping ground with an average elevation between 750 to 800 feet mean sea level (MSL). The site topography does not pose any construction limitations or challenges.
Geology – Nāʻālehu soils are on the south and east low windward mountain slopes on Mauna Loa Volcano at elevations from 750 to 1,200 feet. The soils are on all hillslope positions of constructional landscapes consisting of nearly level to very steep ash fields on lava flows. Slope gradients range from 0 to 70 percent. The soils formed in basic volcanic ash. Hawaii island is the most active volcanic activity with four active volcanoes. Nāʻālehu is on the slopes of Mauna Loa, the largest volcano on earth. According to USGS, this site is located in Zone 3 having moderate risk, but less hazard since greater distances from recently active vents and because of topography.
The island of Hawaii is currently classified as seismic zone E, high hazard (Source: Uniform Building Code (UBC)). The facility will be constructed in accordance with the UBC to withstand earthquake forces.
Land Use – the project is located in the State land Use Agricultural District and Zoned Agricultural by the County of Hawaii. The project is generally bounded by undeveloped lands to the east, west, and south. Some residential housing exists on the northern boundary of the property. The proposed use is consistent with State and local land uses.
Flood and Tsunami – The project site is located outside the tsunami inundation zone. According to FEMA Flood Zone Maps, the solar facility is not located in a flood zone with minimal to no risk.
Noise – Solar Facilities are low noise generating sources and is unlikely that conditions would exceed the 50 dBA limits at the nearest external property line. Short-term noise during construction may be covered under a community noise permit if deemed necessary.
Roadway and Traffic – the primary access to the site will be off Mamalahoa Highway, an improved paved State highway. Temporary construction traffic will have short-term effects due to the delivery of solar equipment and construction vehicles, but long-term impacts will be minimal with less than 4 vehicles per day accessing the site. This part of Mamalahoa Highway is in a low-volume traffic area.
Utilities – The proposed project does not require potable water service and would not affect existing water supplies for the adjacent properties. The facilities would plan to use the Hawaiian Electrics telecommunication network to eliminate any potential burden to existing private or public telecommunications networks. Electrical export of electricity would be through underground or aboveground infrastructure interconnecting to existing power resources along Mamalahoa Hwy. No disruption or impact to utilities is expected as a result of the project.
The project site is currently vacant, open space land, and with a Productivity Class rating of D, the second lowest rating. The project will replace the vacant land use with beneficial productive economic use, e.g., lease from solar facility and production of clean renewable energy to the public utility. The project will not conflict with other adjacent land uses or economic activities. The project is not intended to stimulate or otherwise promote population growth or other economic activity. Therefore, the project is not intended to have a significant effect on the socio-economic environment of the area.
Aesthetical and Visual Resources
The project is located in a relatively low-populated area along the lower slopes of Moana Loa. It gently slopes downward from upslope towards the ocean and equipment and structure will not exceed 8 ft in height. There are no known public vantage points and would not be generally visible from the highway due to existing vegetation and trees. Therefore, the project would not have a significant impact on aesthetic or visual resources.
Day-to-day operations will not generate or produce large volumes or unusual types of solid waste. During construction, solid waste will be generated from the packaging of delivered equipment and would be considered normal commodity waste (e.g., plastic, wood, cardboard). All waste generated will be properly disposed of or recycled at locally permitted facilities. No adverse or significant impacts are expected on the local collection or disposal facilities.
The proposed project will not require large amounts of hazardous materials during construction or during operation. During construction, certain cleaners or corrosion protective material may be used but is maintained in small quantities at the site. During the operation of the facility, minimal amounts of cleaners for the solar panels may be present but would be non-toxic and biodegradable. No known releases of a hazardous substance are known to have occurred during ranching activities. No adverse or significant impacts are expected as a result of the minimal use of hazardous materials.
There are no defined water bodies or wetlands. The site is located above a drinking water aquifer; however, the project will not inject any water into the ground. During construction, erosion and sediment control best management practices would be employed minimizing the potential for water quality impacts. Since the project does not generate any process water or wastewater requiring disposal, the project does not have the potential to significantly affect water quality.
Public Safety Services
Solar facilities pose low-risk fire hazards due to the non-combustible materials used in the equipment. However, nearby uncontrolled ground fires could pose risk to the ground cover catching fire at the facility. The facility will be designed with site access roads meeting local fire code (e.g., 20-ft wide all-weather roads) to allow firefighting apparatus access to the site.
The project will be fully fenced with a locked gate. The facility will not pose a high risk to local police resources and the facility will be remotely monitored and private security forces will be available to investigate suspicious activity.
The proposed facility does not pose a significant health risk to workers. The closest medical facility is the Kau Hospital. The project does not have a significant impact on public safety services.
The closest recreational resource would be local beach spots and hiking trails, but the facility will not pose any significant impacts as a result of operations.
Potential Cumulative and Secondary Impacts
The proposed project supports the State’s goal to produce 100% clean energy by 2045 and will help advance the achievement of that goal. The potential secondary impacts as a result of the development of the project are minimal and will not have significant impacts on the environment or public health and welfare.