| Abstrak/Abstract |
Research on groundwater vulnerability using the simple vertical vulnerability (SVV) method in Wonosari district, Gunungkidul, Yogyakarta was conducted to identify groundwater vulnerability zones that require careful management in the research area. It is very important to know the extent of existing environmental and geological conditions in protecting groundwater from the potential pollution that may arise. In addition, this study also wants to prove the accuracy of the SVV method when carried out in limestone lithology conditions. The method used is the SVV method concerning three intrinsic parameters, namely the type of lithology based on the value of each specific retention of the soil or rock, the thickness of the unsaturated zone, the amount of groundwater recharge, and verified by land use. The nitrate content test in water samples at the research site was conducted to validate the research results. The study results found that two lithology types compose the research area, namely crystalline limestones, which are generally scattered in the southern part, and calcarenite limestones distribution in the central and northern parts. The depth of the unsaturated zone in the study area varies from 0 to more than 40 m, with the groundwater recharge being 438.68 mm/year. The land use of the research area varies from urban regions and rice fields to community plantation areas. The existing parameter overlay results are divided into three groundwater vulnerability zones: medium, high, and very high. The potential sources of pollutions zone are divided into four zones: low zone, medium zone, high zone, and very high zone. Based on the validation results carried out by comparing the nitrate content of groundwater samples taken in the research area, a correlation was found between the potential sources of pollutants and nitrate concentration. Therefore, the research results using the SVV method are considered accurate enough to represent nature’s ability to protect groundwater quality in the research area. The result of the groundwater vulnerability zone by the SVV method is considered accurate enough to represent nature’s ability to protect groundwater quality in the research area. |
