Study On Groundwater Environmental Impact Assessment Of CBM Mining

The influence of groundwater en-vironment of CBM mining includes:the effect on groundwater quality and the influence of CBM mining on underground aquifer.Because the waste water can been almost disposed and is not outside,which on the influence of groundwater quality could been weakened.But the Influence of CBM mining on groundwater resources is becoming more and more evident,we should pay greater attention.In this paper,take Zhengzhuang block Qinshui basin 900 million m3/a production capacity construction project for an example,studying on contents,requirements and methods of groundwater environmental impact assessment of CBM mining.The result shows that:CBM mining project should be the class III construction project and the classification of assessment grade can be generally determined for level three.The main content of the groundwater environment present situation investigation should include the area of natural environment profile,strata distribution,geological tectonic characteristics and hydrogeological conditions and so on.The investigation on the distribution of aquifer which has water supply significance in the area shoud be focusd on.And at the same time groundwater pollution situation and regional environmental hydrological geological problems should be investigated.The present situation of groundwater quality and groundwater level monitoring in evaluation area should be monitor.And the single factor index method should be adopted to evaluate the status quo of the groundwater environment.The prediction should be focused on the damage to groundwater resources of CMB mining,the degree of regional groundwater level change and its influence scope.The contents,requirements and technical methods of groundwater EIA can be used on the project of CBM mining.Because the project of CBM mining has its characters and the influence of groundwater environment is different from other construction projects,on the basis of following the guideline principle,we need to adjust the assessment contents and take the appropriate assessment methods.Some problems still exist in the process of the application of the guideline in CBM mining project.Status monitoring frequency is on the high side.Monitoring points are too much.Hydrogeologic parameter data is difficult to collect.The prediction of environmental impact is difficult.The paper discusses these problems and puts forward some countermeasures.We can suitably decrease the monitoring frequency.Related departments and enterprises should strengthen cooperation.Relevant departments need to write prediction software as soon as possible.