Groundwater Characterization of Cihaur Watershed Basin, Batujajar and Adjacent, West Bandung District, West Java, Indonesia

The study was conducted based on data from outcrop, well data, and springs with field orientation method assisted by the use of GPS and measurement tool physical and chemical properties of groundwater. Geological conditions investigated were geomorphology and stratigraphy, geomorphology unit study area consists of four units, namely geomorphology unit of strato volcano body, foot of strato volcano, intrusion units, and plains units and the river drainage patterns are parallel and subparallel. Stratigraphy in the study area are volcanic breccia (Qbv), Unit Andesite (Qa), Unit Tuff (Qtf) and Unit Clay Tuffan (Qlt). The characteristics of the groundwater of the study area are in form of the physico-chemical, major elements, and hydrolic parameter of the groundwater aquifers. From 27 locations, the water quality assesment by physico-chemical properties is classified as fresh water category and based on chemical major elements, has been classified 8 facies which are located in the study area. Then, there are two lithologies which act as aquifers ie, tuff and volcanic breccias. Conductivity values in the range of volcanic breccia aquifers respectively 0,128 m/day and 0,288 m/day, transmitivity (T) ranges respectively 1,9296 m2/day and 4,32 m2/day. The value of conductivity in tuff aquifer is 0,063 m/day, transmitivity (T) is 0,95 m2/day. While lithology Qlt (Clay tuffan) is lithology with very low productivity of groundwater or called groundwater rare area (akiclud) and the rock units Qa (Andesite) is a non-aquifer that is the absence of groundwater in these rock units (akifug).


Introduction
The need for water resource increases with the times. The use of groundwater increases due to the contamination of surface water. Therefore, the need for in-depth study on the state of subsurface water/groundwater is very important to support the management of water as part of the planning area. In order to know the geological conditions of the research area for the determination of the aquifer typology, the hydrogeological conditions of the study area and the potential of ground water in the area of research.

Methodology
of groun pH, and paramete Wave-Fi aquifer a

Resul
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Geom
The stud [3]  In general, the rocks in the study area consists of volcanic rocks that make up the body of volcanoes. Based on field data conducted by the Laboratory of Hydrogeology and Environmental Geology, University of Padjadjaran and compared with Regional Geological Maps of Bandung sheet by [4], in order to formed the unofficial naming of these lithologies, outside of lithostratigraphy and litodemik rocks units can be interpreted that existing lithologies research areas with the sequence of the oldest rocks to rock the youngest, namely: Unit Volcanic Breccia (Qbv), Porphyry Andesite (Qa), Unit Tuff (Qtf), and The Deposition of Lake (Qlt). These are primary data which obtained from direct measurement from the 27 locations of the research area used a Hanna Multiparameter Probe instrument.

Groundwater Characterization
In this study, the parameters are classified is a major chemical element that is (Ca, Mg, Na, K, HCO3, SO4, Cl) and physico-chemical parameters such as pH, electrical conductivity (EC), total dissolve solids (TDS). From these data can be analyzed descriptively about groundwater characterization. On springs and wells, based on the classification [5] classified the water quality fresh water category (for TDS value 0 -1000g / m3) and also classified as fresh water (for grades DHL 30-2000 S).

Hydrolics Condition of Groundwater Aquifer
Hydraulic parameters of the aquifer can be known through the pumping test. Pumping test performed on three wells owned by local residents to determine aquifer hydraulic parameters. These wells are shallow aquifer to represent basins in the study area. Hydraulic parameters of the aquifer that develops can be obtained from a pumping test in the study area were analyzed using methods Neuman Wave-

Conclusion
The characteristics of the groundwater of the study area are in form of the physico-chemical, major elements, and hydrolic parameter of the groundwater aquifers. From 27 locations, the water quality assesment by physico-chemical properties is classified as fresh water category and based on chemical major elements, has been classified 8 facies which are located in the study area.Then, there are two lithologies which act as aquifers ie, tuff and volcanic breccias. Conductivity values in the range of volcanic breccia aquifers respectively 0,128 m/day and 0,288 m/day, transmitivity (T) ranges respectively 1,9296 m2/day and 4,32 m2/day. The value of conductivity in tuff aquifer is 0,063 m/day, transmitivity (T) is 0,95 m2/day. While lithology Qlt (Clay tuffan) is lithology with very low productivity of groundwater or called groundwater rare area (akiclud) and the rock units Qa (Andesite) is a non-aquifer that is the absence of groundwater in these rock units (akifug).