Evaluation Of Groundwater Resources In Junhe River Basin Of Pingyi

Water resources are closely linked with economic development and social progress. As groundwater resources constitute an important component of water resources, reasonable exploitation and utilization of groundwater resources guarantees the sustainable development. Junhe upstream basin is among the mountainous regions in the middle of Shandong, which is lack of groundwater resources, and the carbonate karst groundwater is the important water supply sources in it. With the development of economy, the demand for water resources grows barger and barger, so the contradiction between groundwater supply and demand in this area is increasingly prominent. Therefore, there is an urgent need to evaluate the groundwater resources.Based on comprehensively collected data on geology, hydrogeology, weather, social economy and other factors, we made a groundwater evaluation about Difang carbonate karst groundwater system in the upstream of Junhe River basin, and Difang carbonate karst groundwater system was abundant of water resources and had a relatively independent boundary. Firstly, we adopted groundwater numerical simulation software GMS to build an 3D solid model of the evaluation area, so the visual geologic structure of evaluation area had been achieved. Second, the Solids-MODFLOW option was applied to translate the 3D solid model to 3D Grid MODFLOW model, the hydrogeological parameters root in solid parameters. So the relationship between hydrogeological parameters and groundwater evaluation model become unified, this could improve the precision of numerical modeling. The year of 2013 was classed as equilibrium year, the groundwater flow field was simulated, and the sources, sinks and hydrogeological parameters were adjust to fit and demonstrated, and the results showed that the precision of model could meet the requirements of groundwater numerical simulation.Based on the established groundwater resources evaluation model, the Difang carbonate karst groundwater system was set as research object, its water balance in the year of 2013 was analyzed, and the dynamic of the groundwater flow field in the future was predicted. The water balance results in it showed that the total supply of Difang karst water system was 9.27054x 107 m3/a, the total groundwater discharge was 9.25895 x 104 m7/a, and the equilibrium deviation was +11.59×104 m3/a, which was the positive. To predict the dynamic change of groundwater in the next decade, three different types of groundwater exploitation were designed. Prediction results showed that:the continuing development type would larger the groundwater depression cone, the equilibrium and stabilization type could alleviate the groundwater balance between supply and demand, and the thrift and protect type was able to decrease the Karst collapse risk.According to the results of groundwater comprehensive quality evaluation, most of the groundwater samples were Ⅳ standard, most of simples of nitrate factor evaluation results showed V standard. The correlation analysis between nitrate, single component and comprehensive quality evaluation manifested, nitrate had a heavy contribute on groundwater comprehensive quality evaluation. Therefore, groundwater pollution in evaluation area was serious, and it was urgent to improve the quality of groundwater.