| Beijing is the politic capital of China as well as cultural and economic center. As a widow of China, it shows that all kinds of exchanges inside and outside the country are taking placing in this metropolitan city. By lacking of overall city design, without symmetrical, completed geological information, spread of city area, intense architecture and economical activities, depletion of natural nutrition ability, the environment has been polluted and are getting worse with overburden demand of the geological resources by the development of city. Subsequently, it comes up with some serious environment problems. Recently about the 2/3 of water supply of Beijing is coming from the pumping water, and Beijing is one of few big cities in world major depending on the groundwater resource. However, even with intense shortage of utility water, the limited water resources of Beijing, particularly the groundwater, are facing the degradation problem. As the results of pollution, the deleterious water is threatening the safety of the water plant, making the situation of water shortage even worse for Beijing. Based on the acknowledge of the current status of underwater of Beijing plain areas, combined with hydrogeological properties, this project is going to make a comprehensive analysis for the Beijing suburbs underwater space distribution, disciplines and pollution evolution and tendency, and the come up with systematically completed geological suggestions for the city lay out, overall adjustments and protection of underground water in the future. Till now, the relatively better quality of groundwater is at the nearby plain area, in which most excellent groundwater is located at Haidan section, chaoyang north section, changping west part, southeast part of daxing, east of tongzhou, northeast of shuxi, huairou, pinggu, and yangqing areas, totally about 4511km2. The major water pollution factors of these plain area are the total hardness, The salt of nitric acid and resolved solid. Among these factors, the total hardness is most serious factor, well passed the safety standard. This irregular contamination area is about 820km2: east to Chaoyang 18 Dian area, west to Fentan Wangzhuo, Fangshan area, south to Fanshan hulu, Daxing Huang town, and north to Huang temple at urban area. According the analysis of the groundwater quality discipline, it can be seen that the suburb area groundwater pollution has a close relationship with natural environment conditions and exploitation methods. The primarily pollution area are allocated at the 4th groundwater, the intermediate state from the single to multiple water containing layers, as well as the top half of Yongding river deposited area, and the central part of city are. From the surface to underground, 1st and 2th pressured water layers have different levels of contamination, even deep into 90-meter. Fortunately the quality of the lower layers of the pressured water is relatively better, although the contaminations of the total hardness, HNO3 salts, resolved solids are over the limits for the near surface water (0-60m) at the Beijing downstream area, such as the southeast part of Chaoyang, the north part of Daxing area. There is a tendency of deterioration for the quality of groundwater, and the deeper layers water quality is better than the topper layers. By comparison the 1973 to 2000 data, it can be found that the quality of water is obviously worsen at the central & south urban area, and the total hardness is increased dramatically in some areas, called serious polluted area by over 50% increasing. Nevertheless, the total hardness is decreased about 10% at the east, parts of Chongwen section of city, and the quality of water is being improved somehow. The history of groundwater pollution at Beijing outskirts can be described into four categories according to changing discipline of the chemical types, total hardness, The salt of nitric acid for the 4th groundwater:Original phase: During the 50-60's in 20 century, the scal... |
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