当矿床交付开采时,有时勘探孔封孔质量差,并常常在若干含水层中专门留下装有过滤器的测压钻孔。在评价地下水储量和寻找深处贮存工业废液的密封层组的地质勘探工作结束后,类似的情形也可见到。众所周知,不封孔或封孔质量不合格的钻孔乃是矿床附加充水和供水含水层受污染的根源。为了定量评价通过钻孔不封闭井管的越流量,可见下面实例(图1)。假如揭露含水层Ⅰ的钻孔以定流量 Q 抽水,在抽水影响带范围内布置观测孔,观测孔的过滤器部分还揭露含水层Ⅱ。为简化例题,设含水层Ⅰ和Ⅱ在抽水前引用的承压水头值、导水性和压力传 When the deposit is delivered for mining, sometimes the quality of the hole in the hole is poor, and pressure-bearing boreholes with filters are often reserved in several aquifers. A similar situation can be seen after the geological exploration work on the seal layers, which evaluate groundwater reserves and search for industrial waste liquids stored deep inside. It is well-known that unprotected or impervious holes are the source of additional water and aquifer contamination in the deposit. In order to quantitatively evaluate the over-flow rate of a well that is not closed by drilling, the following example can be seen (Figure 1). If it is revealed that the borehole in aquifer I is drained at a constant flow rate Q, observation holes are arranged within the pumping zone and the filter section of the observation hole exposes aquifer II. In order to simplify the example, we will consider the pressure head value, water conductivity and pressure quotation of aquifer Ⅰ and Ⅱ before pumping