Mining activities can affect the availability of groundwater both in quantity and quality. Example of mining activities that can cause pollution are overburden stockpiling, construction of haul road facilities and infrastructure, coal processing and stockpiling activities, workshops, and domestic waste disposal. One effort to maintain groundwater is to analyze the groundwater vulnerability. This research was conducted to analyze the vulnerability of groundwater to pollution of PT. X in Balangan, South Kalimantan. The method used to assess groundwater vulnerability in this study is the GOD method (groundwater occurrence or aquifer type, overall lithology of aquifer, and depth of groundwater). Determining the groundwater vulnerability class with this method will be based on three parameters, namely type of aquifer, lithology or rock type, and depth of groundwater table. The GOD method divides each parameter into several classes in consonance to the weight of each parameter corresponding to the effect on groundwater vulnerability. Based on the results of the analysis, it is indicated that the area of PT. X is included in the category of negligible and moderate vulnerability. The results of the analysis can be used for recommendations for groundwater management in the study area. The GOD method can also be used to determine groundwater vulnerability in urban areas that have different land uses.