A comprehensive book, free on the web: Rock Fractures and Fluid Flow – Contemporary Understanding and Applications. This 1996 publication was prepared by the following: Committee on Fracture Characterization and Fluid Flow; U.S. National Committee for Rock Mechanics; Geotechnical Board; Board on Energy and Environmental Systems; Commission on Engineering and Technical Systems; and the National Research Council.

The focus is fluid flow in rock masses around deep-level radioactive waste disposal mines. But the principles and practical implications are equally applicable to ordinary mines and ordinary mining problems. With over 550 pages it contains all the information you are likely to need as introduction, background, or inside insight to using a computer code, such as those from FracMan to solve a real-life problem.

While on the topic, the National Academies Press is a superb resource of free on-line, e-books. As is book.Google.com. I tried them out for the obvious keywords “rock fracture fluid flow” and the book noted above came up first in a completely different e-version. Then there were 621 more books with these keywords. It was only by about book 200 that they were not that relevant. So if you are interested in the topic and have the time, there are at least 200 free, e-books for you to read on fluid flow in rock masses, mostly around mines.