Abstract: The curtain grouting method has been gradually becoming an important means for controlling mine groundwater flood in karst regions and reducing mine drainage and mining costs and protecting the underground personel security and regional water environment. Mine curtain grouting is a kind of typical hidden engineering,that is to say, the construction quality of it can not be evaluated directily. It will take us a lot of time to wait for the evaluation results by conducting the experiment of mine pit drainage, Besides that, it is very difficult to make up for engineering quality afer the formation of underground workings system, so, the inspection hole become the perfect means of evaluating the engineering quality.Taking the Nanlizhuang iron curtain grouting engineering as the research object, the superimposed effect method of grouting volume and permeability rate, frequency curve, discrete coefficient, grouting volume curve and grouting stone distribution statistics are applied to provide some important baisis for the design of inspection hole. The good perfect effect is obtained in line with the research results.

Key words: Curtain grouting, Quality evaluation, Inspection hole, Grouting volume, Permeability rate