This proposed project is an effort by the University of Hawai‘i to better understand the unique hydrology of the Lāna‘i Island. Water wells within the Pālāwai Basin, the caldera region of Lāna‘i volcano, tap high level brackish water that is at elevated temperatures. This is the only location in the state where brackish water exists above sea level, and here it is hundreds of feet above sea level. The origin of this high-level brackish water is unknown. The proposed action is to deepen two existing wells within Lāna‘i’s Pālāwai Basin using core drilling technology (core will be less than 4 inches diameter). This study will improve the overall understanding of the groundwater system within the Island of Lāna‘i and therein provide valuable information for conservation of this resource. It will expand our understanding of the dynamics of groundwater systems within specific geologic regimes (the caldera regions of the Hawaiian volcanoes), which is applicable to groundwater management statewide.