Groundwater Suitability for Drinking and Agricultural Usage in Yinchuan Area, China

On the purpose of assessing the degree of ionic toxicity of groundwater sources as irrigation and drinking purposes, groundwater samples were collected and analyzed for various elements of major cations and anions such as Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl⁻, HCO₃⁻, SO₄^2- CO₃^2- and other minor ions Fe, NH₄-N, NO₂-N, NO₃-N, As, Gr⁶⁺, Cd, Hg, rand F as well as such important chemical parameters as Total Dissolved Solid (TDS), Total Hardness (TH), pH, COD and odor. The TDS, Sodium Adsorption Ratio (SAR), Soluble Sodium Percent (SSP) and Residual Sodium Carbonate (RSC) were used for irrigation suitability assessment. The results show that the groundwater in the study area is not entirely fit for direct drinking with respect to TDS, TH, Fe, F, cr and solo. In some of the samples collected, the concentrations of these constituents exceed the permissible limits of the Standards for Drinking Water Quality of China. Based on TDS, 75% of water samples are suitable for drinking and 80% of samples are fit for drinking based on TH. Heavy metals such as As, Gr⁶⁺, Hg and Cd are well below the permissible limits. Based on TDS, SAR and RSC, all the samples are suitable for irrigation, whereas, based on SSP, S17 and S3l are unsuitable for irrigation. However, S17 and S3l can be still used for irrigation ifthey are mixed with other samples, and therefore all the samples are classified into suitable group for agricultural irrigation.