Application of the Fuzzy Method in the Comprehensive Evaluation of the Environmental Quality of Shallow Groundwater in the Liaoning Central Area

Ten indicators including Fe, Mn, total hardness, NO^-₂, NH⁺₄, Cl^-, F^-, C₆H₅OH, Ba, Be were selected as proxies for the quality of shallow groundwater in Liaoning central area. The groundwater quality was calculated according to national standards by the fuzzy comprehensive evaluation method. The integration of environmental quality characterized by high content of iron and manganese ions is poor and most of the water cannot be used directly as drinking water. More than half of the total groundwater in the working area is poor in quality, and occurs mainly in the middle and lower Liaohe alluvial plain. The main factors affecting water quality are Fe and Mn contents and total hardness, followed by NO^-₂, NH⁺₄ and Cl^- content. The growing need to perform quality evaluation of groundwater makes this method both important and prominent and provides scientific data for water resources protection and planning.