Groundwater inflow into excavations (quarrys)

[QU]

We are having trouble finding information on estimating groundwater inflow into an excavated quarry. If anyone has any information/resources that would be of use it would be much appreciated. thanks.

 

[phillyfrank]

You are likely dealing with fracture flow in rock. You will have to do pump tests to establish the rock mass in-situ permeability, which is not easy and will vary with depth and place. I know people who do this work routinely and can put you in touch with them if you like.

 

[Hambley]

First of all, what type of rock are you quarrying and for what purpose? In sedimentary rocks like limestones and dolomites inflows will consist primarily of

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and seeps along bedding planes plus inflows along joints. With granites or gneisses it will be essentially fracture flow. Estimating inflows on fractures requires a knowledge of several physical parameters: fracture aperture(opening width), fracture spacing, fracture hydraulic conductivity (K sub f), and rock matrix hydraulic conductivity (K sub m). K sub m can be measured in the lab, but the other parameters must be obtained in the field. As Phillyfrank stated, K sub f requires a pump test. Hope this helps.