Environmental Impact & Compliance Plan

Haleakala Solar completed a preliminary diligence review in 2019, which did not identify any material environmental issues. Building off of that assessment, Haleakala Solar will complete environmental and land use permitting studies through 2020 and expects to submit its discretionary permit application in Q3 of 2020.  The project will require a County Special Use Permit which will include a public hearing before the Maui County Planning Commission.

Clearway anticipates designing the project to avoid impacts to sensitive resources including waters under the jurisdiction of the U.S. Army Corps of Engineers (USACE) and implementing best management practices during construction and operation to avoid adverse impacts to state and federally protected species. Clearway will consult with the appropriate state and federal agencies, including USFWS, Hawaii Department of Land and Natural Resources (DLNR) and Division of Forestry and Wildlife (DOFAW). HDOT will be engaged early on the overhead 69kV line across Piilani Highway.

Listing of Permits & Approvals

Maui County Special Use Permit

Issued By: Maui County Planning Commission

Timeline – Clearway plans to apply for this SUP after environmental studies and diligence are complete in Q3 2020. Clearway estimates timeline for securing SUP to be between 6-10 months. [Placeholder: link to application]

Building and Grading Permits

Issued By: Maui County – Department of Public WorksTimeline: Clearway intends to file for the building and grading permits in Q42021.

NATURAL RESOURCES

Biological Resources

Biological Resources

Clearway plans to conduct biological surveys to identify the potential presence of federal and state-listed wildlife and plant species, critical habitat, and jurisdictional wetlands, and will take the appropriate avoidance and minimization measures to avoid or minimize impacts as practicable, based on consultations with state and wildlife agencies. At this time, Clearway does not anticipate incidental take permits from state or federal wildlife agencies would be required.

A Stormwater Pollution Prevention Plan (SWPPP) would be implemented and the NPDES permit would be adhered to during construction to ensure that there would be no releases to jursidictional drainages.

Soils

The project is located on Land Study Bureau (LSB) rated E soils. The project is not located on any LSB rated A or B soils. The soils within the lands surrounding the site are also classified E; these represent the lowest productivity for agricultural lands.

Air quality

There are no expected impacts short or long term to air quality from operation of the project. There are no emissions from operation of solar photovoltaic or battery storage technologies. Each year, the energy potentially generated by the project would eliminate the use of approximately 150,000 barrels of oil, which in turn would reduce emissions of carbon dioxide (CO2) by more than 65,000 tons. Other air pollutants for which emissions would be reduced include sulfur dioxide (SO2), nitrogen oxides (NOx), and mercury (Hg).

Noise

The State of Hawaii regulates noise under HAR § 11-46, Community Noise Control, and limits sound generated by new or expanded developments. Noise associated with construction (i.e., operation of heavy equipment or construction vehicles) may require a noise permit if construction-related noise exceeds 60 dBA for more than 10 percent of the time within any 20-minute period at or beyond the property line during the daytime, or 50 dBA during nighttime hours. Based on Clearway’s experience on other solar projects, a noise permit has not been necessary as construction does not exceed state thresholds.

Ground-mounted inverters and transformers make a humming noise during daytime hours when the solar array generates electricity; this sound is typically inaudible in areas approximately 50-150 feet from the boundary of the array. There may be some sound generated from switching gear associated with the substation, but this is expected to be minimal. Another noise source would include mowers and weed whackers used for vegetation control. These are very minor nuisances and given the location of the project are not expected to impact any nearby uses or be considered atypical noise.

Aesthetic/Visual Resources

The project site is in a largely undeveloped area, with no immediate neighbors. The closest residence is near the Maui Nui Golf Club, approximately 0.5-mile west of the site.  The site is bordered to the south by a Monsanto-affiliated farming operation, and to the southwest by an existing small solar facility.  There is no development to the east or north.

As the solar panels would be mounted relatively low to the ground with trackers running north-to-south (to maximize the solar radiation as the sun tracks across the sky), views of the solar panels are expected to be minimal. Clearway intends to design the Project and use landscaping as a visual screen to reduce the potential for any adverse views.

Visual impact assessments will be performed and visualizations shared with the community as part of the community engagement process.

Hazardous Materials

At this time, hazardous materials are not anticipated to be stored onsite. However, likely hazardous materials to be used onsite would include diesel fuel for back-up generators, vegetable oil for transformers, pesticides for vegetation management, cleaning chemicals, and sulfuric acid required for batteries in the substation and storage. The project would not generate any hazardous waste. Consultation with the Department of Health will take place related to the inclusion of battery storage with the project.