part Section I: Isotope Fundamentals -- chapter 1 Chapter Fundamentals of Environmental Isotopes and Their Use in Biodegradation -- chapter 2 Chapter Analysis of Stable Isotopes -- chapter 3 Chapter Principles and Mechanisms of Isotope Fractionation -- chapter 4 Chapter Isotope Fractionation during Transformation Processes -- part Section II: Isotopes and Microbial Processes -- chapter 5 Chapter Isotopes and Aerobic Degradation -- chapter 6 Chapter Isotopes and Methane Cycling -- chapter 7 Chapter Isotopes and Processes in the Nitrogen and Sulfur Cycles -- part Section III: Isotopes in Field Applications -- chapter 8 Chapter Investigating the Origin and Fate of Organic Contaminants in Groundwater Using Stable Isotope Analysis -- chapter 9 Chapter Stable Isotope Fractionation of Gases and Contaminant Vapors in the Unsaturated Zone -- part Section IV: Isotope Emerging Areas -- chapter 10 Chapter Isotopic Labeling in Environmental and Biodegradation Studies -- chapter 11 Chapter Combined Use of Radiocarbon and Stable Carbon Isotopes in Environmental and Degradation Studies -- chapter 12 Chapter Nontraditional Stable Isotopes in Environmental Sciences.