2019-03-27 Meeting Minutes (EMC)

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which allows process interactions to occur between the water and the soil. These will be the first SAT ponds in Hawaiʻi. • On Chair Bennett’s question about how confident they are that the ponds will perform as intended, given the Big Island’s fractured lava and blue rock, Mr. Lekven said they had a recent demonstration project. They are still waiting for the lab results, but the preliminary data was very positive, with greater than 90% removal of the phosphorus. “Our preliminary results are fantastic.” • They have two primary purposes for the SAT. The first is to dispose of effluent that can be recycled. The second is to remove phosphorous, but there will be additional benefits with the removal of trace heavy metals, trace organic compounds, and personal care products. They will be adsorbed into the media of the soil. • The sand will eventually become saturated. They are projecting a useful life of 30 to 40 years for the SAT, partly based on the volcanic rock here, which has so much iron in it that sucks up the phosphorus. There will be monitoring systems in place to confirm performance over time. Commissioner Gaffney commented that all of the R-1 use figures depend essentially on the developments happening, but the various QLT projects seem to be stalled because QLT is land rich and cash poor. The future regional park has been discussed forever, but there is no apparent forward motion that he is aware of. Director Kucharski said the EA is in progress on the regional park, and there is a commitment to double pipe the entire park. Mr. Lekven added that their project includes extending an R-1 pipeline to above the top of the SAT site, where they will put in a small storage tank and make the R-1 water available for use for construction and when the park is phased in. Regarding the EIS, Chair Bennett expressed concerns about irrigating with the wastewater because of its chloride and sodium. In addition, the EIS shows a substantial amount of nitrogen in the irrigation water, with an inconsistent forecast on how much nitrogen will be used per acre of grass. Mr. Lekven said there is an opportunity to make sure salt-tolerant vegetation is planted. The recycled water will be an improvement to what Kohanaiki has been using, and the chloride levels will be comparable to the Lahaina reclamation facility on Maui, which has watered the Kaʻanapali golf course for 20 years. The Big Island’s soils are so young that there is very little clay in them, which is what causes a sodium hazard. The county has done a fantastic job in making repairs to the collection system, patching up areas where brackish groundwater infiltrated the sewer and caused increased chloride levels. The current chloride levels are about 600 to 700 milligrams per liter, which is a substantial improvement. The system has been designed so that the water coming out of the constructed wetland will have a low nitrogen content, and the county will be able to blend it with the water that is going off to create the R-1 recycled water so the nitrogen content is tailored. 8