Catalyst will connect you to thousands of articles on silica sand mining, including from newspapers around the country.
Private company information can be hard to obtain but these sources will provide some information, enable you to get articles from trade publications and industry profiles, which provide you with the "big picture." (Government documents are also a good source of industry information.)
Search these political science, social science, and broad cross-disciplinary indexes for scholarly articles to place this case in context. Remember to search using broad concept terms. Learn the scholarly conversation surrounding these issues and understand the debates. How to get started?
These websites are often rich sources for research because they have lists of links and bibiliographies.