Why Desalination? Q A Q A

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1 Why Desalination? Why do we need a desalination facility? Fresh water makes it possible to undertake the developments needed for a sustainable Lāna i. If the island stays as it is, without any additional fresh water, Lāna i and its economy will remain stagnant. For young people to return to live and work on Lāna i, we need to develop an economy that creates jobs and makes it possible to build homes and grow food for them. Pūlama Lāna i s goal is to create a model of sustainability, and the availability of more water is key to making this happen. Who will benefit from this plant? The people of Lāna i will be the ultimate beneficiaries because the facility will reduce reliance on the islands aquifer. long with protection of the watershed, reducing reliance upon the aquifer should enhance water security for the island. Has desalination worked in other areas? Desalination facilities have been operating successfully across the world for more than 40 years and include a number of islands that use desalinated water as their only potable water source. How does the planned desalination facility compare to other facilities as far as overall capacity? IDE s Carlsbad, California s desalination facility will produce 50 million gallons of water per day. The Lāna i facility will start by producing 2.5 million gallons per day and increase to 5 million gallons per day in the next expansion phase. What s the cost of the facility and how will you get back the money you invested? Lāna i needs water. For Lāna i to grow and realize a sustainable vision, a second reliable source of water must be developed, in addition to the high-level aquifer. t this stage of the project, Pūlama Lāna i has not identified all of the costs, but is making this capital commitment to help support the vision of achieving a sustainable Lāna i. What is the life of the installation? lthough there is a life span for pumps and membrane filters, a normal maintenance and parts-replacement program will keep the desalination facility operating for a long time to come.

2 Understanding the Process How will the concentrate (hypersaline water) from the desalination facility go back into the ocean? Will it affect the ocean ecosystem? The desalination plant will utilize saline groundwater as its feedwater supply. The saline groundwater will be drawn from depths that are well below the thin and brackish basal lens so as not to disturb the lens itself. The salinity of this feedwater supply will be essentially identical to seawater. bout 42 percent of the feedwater will be the desalinized product water for drinking water and irrigation use. The salts removed from the product water will be in the remaining 58 percent of the feedwater, referred to as the concentrate. lthough Pūlama Lāna i is investigating possible uses of the concentrate, it will initially, at least, be discharged into disposal wells at depths between 150 to 400 feet below sea level. The concentrate will be about 1.8 times as salty as sea water. It will first go into disposal wells and will then diffusively discharge into the ocean at a depth substantially greater than 400 feet below sea level and more than two miles offshore. The salt added to the concentrate will make it heavier than saline groundwater or seawater. This means it will tend to sink deeper rather than rise as it moves from the disposal wells toward the ocean. From the time it enters the wells until it is diffused into the ocean offshore, preliminary studies indicate it will take two or more years for it to travel from the disposal wells through the bedrock and into the ocean. Mixing into saline ground seawater along this lengthy travel path will mean that when it reaches the ocean it should have about the same amount of salinity as the ocean water, so it should have no effect on the ecosystem. However, Pūlama Lāna i is also performing offshore monitoring to ensure the accuracy of the preliminary studies. Baseline marine data has already been collected, and will continue to be collected, to describe the existing baseline conditions inside and outside of Hulopo e Bay, in Mānele Harbor, and the area downslope from the disposal wells before the initiation of the desalination project. Comparing this baseline to data collected after the desalination project is operating will reveal if the project is resulting in changes to water quality within the survey areas. What will be going into the ocean and where? If concentrated salt water is going into Hulopo e Bay, will it disturb the marine life? The concentrate disposal wells are about 1 mile west of Hulopo e Bay. This location is also down current from the bay, so no concentrate will be flowing into Hulopo e Bay. The salinity of the concentrate is denser than seawater so it will sink and diffuse as it travels through the bedrock to the ocean. By the time this water comingles with the open ocean, it will be of essentially the same salinity, so there will be no effect on marine life at the point of entry. Why not use brackish water since it contains less salt? Pūlama Lāna i has made the decision to use saline groundwater rather than the brackish basal lens so as not to change the discharge of groundwater into Hulopo e Bay. However, the reality is that the amount of flow in the basal lens is very modest. Over a period of time, wells attempting to tap the basal lens would see the pumped water salinity rise and approach that of seawater.

3 When the concentrate is put into the disposal wells, will it raise the temperature of the ocean water? Has there been any testing of water quality or temperature? Results from the first two supply wells establish that the saline groundwater delivered to the desalination plant will be 78 to 79 F. The desalination process will increase the temperature of the discharged concentrate by less than one degree over that of the incoming feedwater. Results from the first of the disposal wells indicates that the temperature in the receiving saline groundwater is between 77 and 78 F, possibly one to two degrees cooler than the delivered concentrate. s the concentrate mixes with saline groundwater over its more than two year travel time to reach the marine environment, both its salinity and temperature will be decreased to ultimately become essentially identical to those levels in the receiving saline groundwater body. What is meant by Pre-Treatment? Pre-Treatment can consist of a multi-media filter which removes particles greater than 75 microns (or milimeters) and a cartridge filter to remove particles greater than 10-microns prior to entering the RO element array. The pilot testing will determine the exact pre-treatment needed. ll chemicals that may be used in the pre-treatment process will have National Sanitation Foundation (NSF) 61 certification and are allowable to be used in drinking water and are environmentally safe. What is the Post treatment noted in the Desal process. Is it poison being put in the drinking water? Post-treatment consists of ph adjustment with carbon dioxide followed by the addition of calcium carbonate into the product water. This process also reduces the corrosion affect the water would otherwise result in pipes. This is also described by the Langelier Saturation Index (LSI). The additives are non-hazardous and non- toxic. What other chemicals are used in the drinking water? In accordance with the EP and State Dept. of Health (DOH) drinking water regulations, hypochlorite (bleach) is added to provide residual chlorine in the potable water to kill any microbial growth in the water. This is the same process used with current potable water from our drinking water wells in Lāna i City. Why Liquefied Natural Gas? What is the role of MECO in the desalination plant? Since MECO is not able to provide all of the required power, Pūlama Lāna i will be developing a source independent of the MECO grid and will work with MECO to integrate renewable energy sources to supply power to the facility. Why do you need Liquefied Natural Gas (LNG) for the power plant and how will it be brought to Lāna i and stored? Through Hawaii Gas, Pūlama Lāna i will be shipping in 40-foot ISO containers of LNG from the West Coast to fuel the desalination facility. These containers will be stored in a secured area in the Miki Basin area. Empty containers will be shipped back to the West Coast for refilling. The supply of LNG containers on island will be sufficient to cover the

4 demand for an extended period, even if two barge cycles are missed. The desalination plant will have state-of-the-art detection systems that identify hazardous situations and automatic shutdown systems that halt operations in cases of emergency. Why LNG? Were other fuels considered? While Pūlama Lāna i continues to research and plan for additional renewable energy generation, LNG is the cleanest fuel alternative to develop the first phase of firm power production for the desalination plant. It is also inherently safer to manage and transport. It is the same fuel that MECO plans to use at the Miki Basin power plant in the future. Pūlama Lāna i will explore all options for renewable energy, including mini-wind, also called community-scale wind, solar, waste to energy and other emerging technologies. However, these are not expected to be able to be permitted and developed in time as an immediate source of power for the desalination facility. Pūlama Lāna i would like to assure residents that there will be no nuclear power. dditional information on LNG related to safety and benefits can be found on Hawaii Gas website Where Does the Ground Seawater Come From? Why not draw water directly from the ocean? Drawing water from the ocean would require that a large amount of particulate matter from plants and marine life would have to be removed by pre-treatment prior to desalination. Saline groundwater beneath the basal lens does not contain biomatter as it has been filtered moving through volcanic rock. Drawing water directly from the ocean would also require the construction of some form of pipeline extending from the shoreline to a distance into the ocean where water quality would be acceptable. Do federal rules regulate water injection wells? Federal rules govern all types of disposal wells, including the type that will be used to dispose of the concentrate. In Hawai i, the Underground Injection Control (UIC) program of the State Department of Health implements the Federal regulations. Pūlama Lāna i applied for and received the appropriate permit to construct and test concentrate disposal wells. fter the test results are submitted to the DOH UIC, a permit to operate the wells will be issued. What if a test well has problems? Two production source wells have been successfully completed and tested and shown to be able to provide a sufficient amount of water for the desalination project. third supply well will be constructed later in 2014 and its results are expected to be similar. Similar testing will be done at stages of development of the disposal wells. If adequate capacities are no obtained, the alternatives are to drill deeper or to construct an additional well or wells.

5 Will the desalination facility have any positive effect on the aquifer? In theory, drawing less water from the aquifer should aid in its replenishment process. However there are other factors that play into the process so we cannot state with certainty that there will be a positive impact. t the present time, the island s total high level groundwater pumpage averages about 1.9 MGD. bout 1.1 MGD of this amount is used for drinking water and golf and landscape irrigation at Manele. When the desal plant is in operation, it will supply all the water use at Mānele. That means that use of the high level groundwater will drop from 1.9 MGD currently to just 0.8 MGD with the desalinatin facility in operation. This reduction in groundwater use will have a positive effect on the aquifer. What permits and studies are needed for this project? Pūlama Lāna i submitted an pplication for State Land Use Commission Special Use Permit and Project District Phase 2 pproval with the County of Maui s Department of Planning. number of reports where done to study the potential impacts of the wells and desalination plant. Pūlama Lāna i submitted to the Planning Department and Lāna i Planning Commission a project assessment report which summarizes all of these reports. Other Impacts re there other uses for brine besides salt, freezing or for packing fish? Pūlama Lāna i is currently working with experts to identify other options. What kind of jobs will the desalination plant create? For the first two years, IDE will operate the facility. During this time, they will be training Lāna i residents to take over operations. The plant will employ 6 to 10 people. Similar to other drinking water treatment plants, IDE will have an operating and maintenance manual which will address DOH and additional safety regulations for the safe operating of the facility. This will include emergency operating procedures of Lāna i Water Company. What are the impacts of so many contractors? ll Pūlama Lāna i construction contractors are required to attend an Island cultural & community code of conduct orientation to educate them on the uniqueness of Lāna i s way of life and natural resources and environment. Clear expectations will be communicated to all contractor s expected behavior and code of conduct requirements. t the peak of construction for the desal plant, it is anticipated that construction workers may be needed and commuting to Lāna i from either Maui and/or O ahu. How much noise will the plant make? County zoning requires that noise levels be at or below 70 dba. dditional noise mitigation and sound attenuation is being designed to further reduce noise levels. What impact will desalination have on the land? Impact to the land will be limited to the improvement of existing access roads, buildings and water tanks.

6 How does this affect our water rates? Pūlama Lāna i has hired an independent company to look at the water rates for the upcoming rate case mandated by the PUC. The PUC has required Pūlama Lāna i come before the Commission by 2017 at the latest. What permits and studies are needed for this project? Pūlama Lāna i submitted an pplication for State Land Use Commission Special Use Permit and Project District Phase 2 pproval with the County of Maui s Department of Planning. number of reports where done to study the potential impacts of the wells and desalination plant. Pūlama Lāna i submitted to the Planning Department and Lāna i Planning Commission a project assessment report which summarizes all of these reports. What about earthquakes? ll buildings will meet the Maui County building codes for earthquake and hurricane stability.