1. School of Earth and Environmental Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
2. School of Ocean and Earth Sciences, Jeju National University, 102 Jejudaehak-ro, Jeju City 63243, Republic of Korea
3. Jeju Groundwater Research Center, Jeju Research Institute, 253 Ayeon-ro, Jeju City 63147, Republic of Korea