A grouting method is the way to effectively prevent pollutants from spreading into the ground during the digging process of groundwater. This study, based on the comparative study of grouting methods being generally accepted, suggests various construction methods which are suitable for geological structure as follows: In Jeju Island, it is very likely that rocks may fall in shuttered zones such as cracks, joints, scoria layers, and clinker layers. For this reason, it is recommended that materials be injected from the bottom toward the top, not from the top to the bottom. In the case where the amount of injected materials become too large in the areas of cracks or joints because of high level of permeability coefficient, grouting materials which smeared into surrounding areas may cause unwanted cut in the aquifer of the bottom level. To avoid this, the amount of water should be reduced from the typical water-cement ratio of 1:2, and grouting materials with larger grading should be used. If the deep excavation of ground is made in Jeju Island, it is likely to have lots of voids because of geological characteristics. Based on the results of this research, it is found that to construct interior casing, the centralizer should be attached to the casing to prevent the casing from being in contact with the counter fort. The grouting in Jeju Island should be thicker than usual. To avoid over-use of grouting materials, to prevent grouting in more than necessary zone, and to facilitate grouting of void areas, the flexible selection of materials is required. And, to exactly figure out the interior of dug well, an examination through CCTV should necessarily be performed when grouting work is in progress.