Although this website by the U.S. Geological Survey (USGS) does not contain analytical data or methods per se, it is one that contains a complete compendium of links to material on environmental topics under the pervue of USGS. As such, it can serve as a resource and background material for students, faculty or practitioners interested in learning about environmental issues. For example, there is a link to Hg in the environment that discusses the sources, chemical composition and consequence of Hg as related to land or water species. This site is a library of links to USGS articles and reports, some of which may not open. Otherwise, it is easy to browse and link to topics of interest.
The website is available here .