The Hydraulic and Hydrogeochemical Characteristics of Hard-Rock Aquifer in Southern Johor, Malaysia

摘要

Malaysia is known as a country with a significant amount of surface water. It has a high amount of annual rainfall Despite Malaysia's large surface water reserves, increased water demand has made supply scarce. Other sources of water, including ground water, are needed to meet the demand. Nowadays, groundwater exploration in Malaysia has been done extensively to explore the nature of groundwater and its aquifer. The aim of the study is to determine the hydraulic characteristics and the hydrogeochemical characteristics of hard-rock aquifer in Southern fohor, Malaysia. This study will provide information about the nature of the hard-rock aquifer in southern Johor, which will help with groundwater exploration in the future. A well known as SP-TW1 is being drilled in a specific area of Gunung Pulai's southwest. The depth of the drilled well is 126 m. Then, a televiewer survey is done to determine the lithology of the well. A series of pumping tests are also done in the well. After the pumping tests are done, a step-drawdown test, constant discharge test and recovery test are done to determine the hydraulic characteristics of the drilled well. The groundwater is also taken as a sample, and it has been sent to a lab to determine the hydrogeochemistry of the well. Based on the pumping test analysis that has been done, the average hydraulic conductivity of the well is 0.0161 m/d, the average transmissivity is 3.088 m2/d and the average storativity is 0.95. According to the data plotted, the drilled well is also determined to be a double-porosity aquifer and fractured aquifer. The total dissolve solid recorded is 200 mg/L and the groundwater sample from the SP-TW1 well mainly contains calcium-bicarbonate (Ca-HCO_3) which makes it alkaline.