Natar Hot Spring is one of the geothermal manifestations that is located in Lampung Province, Indonesia. About 6 km to the east, another hot spring appears with temperature around 40°C with neutral pH called Cisarua Hot Spring. The Natar Hot Spring itself having temperature 47-54°C with 6.23 pH. Based on the geologic map, the appearance of these hot spring is caused by Lampung-Panjang Fault which trending northwest-southeast. Morphology of the research area is showing a flat terrain topography which composed of Quaternary volcanic rock and metamorphic rock in the basement. The nearest volcano that expected to be the heat source of the geothermal system is the Quaternary extinct volcano called Mt. Betung which is located about 15 km to the southwest. The aim of the study is to analyze the geochemistry of the manifestations and calculate the reservoir temperature. Geochemistry analysis result shows both manifestations are bicarbonate which is formed as a steam-heated water or steam condensates. Geothermometer calculation shows that the geothermal reservoir has temperature 150-160°C with approximately 300 m in depth. All manifestations are originated from meteoric water according to stable isotope analysis D and δ18O data and interacting with carbonate-metamorphic rock beneath the surface based on 13C isotope value. A further geophysics study is needed to determine where the heat comes from.

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Lampung is one of the provinces which have hot spring resource. One of the unique hot springs in Lampung is Cisarua hot spring. Its location is far from volcanic which makes researcher curious with the system of hot spring from Cisarua. Based on the geology map, the location of hot spring is in Lampung Panjang Fault. The aim of this research is to know about type, zone and distribution of hot spring. The method used in this research is magnetic method with combined geochemistry. From geochemical analysis, the type of hot spring in Cisarua is bicarbonate water. It correlates with outflow and shallow zone. Based on 3D modelling of low magnetic anomaly, distribution of hot water is in Center and Southeast research area. Hot water is interpreted by low anomaly.

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Air bersih merupakan kebutuhan dasar yang diperlukan dalam melakukan setiap aktivitas. ITERA sebagai sebuah perguruan tinggi dengan segala aktivitas pembelajarannya pun tidak lepas dari kebutuhan air bersih. Seiring dengan pesatnya perkembangan kampus, ITERA juga membutuhkan perencanaan dalam penyediaan air bersih, salah satunya dengan melakukan kajian terhadap bentuk konstruksi sumur bor air tanah. Hal ini dilakukan karena air tanah merupakan salah satu penyedia air bersih untuk kegunaan dalam jumlah yang besar dan harus dikelola dengan baik. Penelitian ini mengkaji bentuk konstruksi dan letak saringan yang tepat pada sumur bor dengan melihat kondisi geologi dan hidrogeologi serta posisi akuifer. Berdasarkan kajian yang dilakukan, kondisi geologi daerah penelitian berada pada Formasi Lampung dengan dominasi litologi Tuf. Adapun posisi akuifer ditemukan pada kedalaman 6,8 meter. Sehingga, letak saringan dalam pembuatan sumur bor sebaiknya berada pada kedalaman 20-25 meter dan 40-50 meter. Filter yang dibuat pada dua kedalaman ini merupakan langkah antisipasi jika air tanah mengalami kekeringan selama musim kemarau.   Kata kunci: ITERA, air bersih, akuifer, sumur bor.