| Lishu city is located in the west of Jilin Province, which belongs to Siping City and is 4209km2 in area. To Lishu city, the water supply for industry, agriculture and living mainly comes from shallow groundwater, therefore, the water quantity and quality of shallow groundwater has a great influence to production and people's living and has a direct relation to the sustainable development of Lishu city.The topography of Lishu city is higher in the south-east and lower in the north-west, so it has two different physiognomy sights-mountain and plain. The geological and tectonic conditions of the mountainous area are more complex, and groundwater isn't abundant, therefore, the plain area is chosen as the study area. Because Quaternary layer is widely revealed in the study area, the shallow groundwater includes river terraces pore phreatic water which exists in Holocene and Pliocene period, and loess platform pore and fissure mixed phreatic water which exists in Miocene period, that is to say, river terraces pore phreatic water and loess platform pore and fissure mixed phreatic water are the study object of this thesis.Based on the datum including weather, hydrology, geology, physiognomy, hydrogeology and groundwater exploitation, the thesis analyses the configurable characters of aquifers and the recharge, runoff, discharge and dynamic characters of groundwater. On the foundation of completely understanding the geological and hydrogeological conditions, the hydrogeological model is established, and the study area is generalized as heterogeneous isotropyic two-dimensional unsteady flow of phreatic water. On the basis of these, the math equation is established, which is solved using Visual MODFLOW software. In the following, the established model needs to be identified and validated by the water lever datum from Jan 1, 2001 to Jun 1, 2002. The results indicate: the established model fits to the precision demand, and is comparatively right, so it can be used to forecast the coming water level.The deterministic model is established on the basis of many hypothetical conditions, and difficultly simulates the intricate hydrogeological conditions truly. On the other hand, the stochastic model can't reflect dynamics mechanism of groundwater flowing system. Considering all of these, this study combines time-serial model with numerical model and establishes stochastic - deterministic model. In term of current exploitating project, linking to water resource requirement of social ecomony, the groundwater resources is evaluated in the following 10 years. The results show that the study area is in the state of negative balance on the whole, the allowable yield of shallow groundwater is 11717.54×104m3/a, the drawdown is uneven everywhere during the 10 years, the water drawdown in some areas is out of the range of allowable drawdown, such as in the areas of Donghe, Wanfa and in the areas of Lishu town,Guojiadian and Shijiapu.Piper Diagram can't be subject to artificial influence and can inflect universal chemical characters of water samples, so based on lots of water-chemical observing datum and in virtue of Aqua Chem software, the thesis makes off groundwater types of the study area by the way of Piper Diagram. The results show that water-chemical components are comparatively complex in this area. For the cation, Ca2+ is predominant component, Mg2+ and Na+ are the second; For the anion, HCO3- is the primary component, Cl- and SO42 take the second part. In addition, as far as the study area is concerned, the water chemical character has a close relation with topography, physiognomy, stratum lithology and water alternant conditions, plus in the influence of human's activity, so it takes on a certain territorial difference.In contrast to water-chemical observing datum of 1986, the thesis chooses"Ca2+,Cl-,SO42-,HCO3-,NH4+,F-,NO3-,TDS,HARD"as evaluating objects, and separately evaluates water quality in 1986 and in 2001 by the way of mater-element and extension, which takes groundwater quality criterion(GB/T14848-93) as metewand. The results show that the content of all kinds of evaluating objects has greatly gone up, especially HARD. On the whole, water quality in the study area is better, but it is different with regions. The parts of first and second rank terraces along Dongliao River, such as Gujiazi, Xiaokuan, Donghe and Jinshan, have been seriously polluted, which water quality belongs to the forth rank and the main polluting elements are F-.NH4+. and HARD. The thesis analyses the polluting reasons, and puts forward appropriate measures to prevent and cure water resources.Combining the appraisal of groundwater quantity with the appraisal of groundwater quality, the following conclusions can be made out: there exits phenomena of unreasonable exploitation and utilization in part areas, if continuing to exploit groundwater by the current exploiting project, series of environmental and hydrogeological problems will be brought about. Therefore, on the basis of the appraisal results of groundwater quantity and quality, the study area is divided to different water functional areas. According to the actual exploiting layout of the study area, reasonable exploitation and utilization project is put forward, which will be computed by numerical model. The results indicate that the groundwater drawdown is within the range of allowable drawdown. The exploiting quantity not only can meet the groundwater demand of the total study area, but also can satisfy the groundwater quantity and quality of all kinds of departments. Furthermore, this kind of exploitation can't bring about any environmental and hydrogeological problems. Accordingly, this project has some instructing meaning of reasonable exploitation and utilization of water resources and the sustainable development of water resources in Lishu city.
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