Acknowledgments

The great majority of the research described in the following pages has been performed since 1981 while I have been in the employ of Lawrence Livermore National Laboratory, which is operated for the U. S. Department of Energy by the Regents of the University of California. This work was performed under contract No. W-7405-ENG-48 and, since 1983, it has been supported either fully or in part by the Geosciences Research Program of the DOE Office of Energy Research within the Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences. The EMSP or Environmental Management Sciences Program of DOE was also a major source of support for several years.