Containment barrier systems are among the most widely used technologies for remediating contaminated sites. Various structures have been engineered to address site-specific needs, while barrier selection depends largely on whether regulatory requirements are prescriptive, or performance based. This publication provides an introduction to the design and construction of different containment barriers for low-level radioactive waste generated from remediation activities: basal (bottom) liners, final covers, in situ vertical barriers and in situ permeable reactive barriers. Practical aspects of each structure are discussed in theoretical case studies, which allow remediation project designers, implementers and regulators to make more informed decisions about the use of these barriers.

• 1. INTRODUCTION
  • 1.1. Background
  • 1.2. Objective
  • 1.3. Scope
  • 1.4. Structure
• 2. PRESCRIPTIVE VERSUS PERFORMANCE BASED APPROACH
• 3. WASTE CONTAINMENT LINERS
  • 3.1. Function of a liner
    • 3.1.1. Advection
    • 3.1.2. Diffusion
  • 3.2. Types of liner system
    • 3.2.1. Single liners
    • 3.2.2. Composite liners
    • 3.2.3. Multiple liner systems
    • 3.2.4. Leachate collection and removal systems
    • 3.2.5. Leakage detection systems
  • 3.3. Site-specific conditions
    • 3.3.1. Performance criteria
    • 3.3.2. Climate
    • 3.3.3. Availability of materials
  • 3.4. Failure mechanisms
    • 3.4.1. Chemical incompatibility
    • 3.4.2. Desiccation (prior to waste filling)
    • 3.4.3. Freeze–thaw effects
    • 3.4.4. Installation defects and problems
    • 3.4.5. Durability
    • 3.4.6. Stability on side slopes
    • 3.4.7. Clogging of drainage layers
  • 3.5. Design of liners
    • 3.5.1. Conceptual design, performance prediction and iteration
    • 3.5.2. Detailed design
  • 3.6. Performance monitoring
  • 3.7. Case studies
    • 3.7.1. The Boršt mill tailings site, Zirovski Vrh uranium mine, Slovenia
    • 3.7.2. In-pit tailings disposal at the Langer Heinrich mine, Namibia
• 4. FINAL COVERS FOR WASTE CONTAINMENT
  • 4.1. Purpose of final covers
  • 4.2. Types of cover
    • 4.2.1. Resistive barrier covers
    • 4.2.2. Evapotranspiration covers
    • 4.2.3. Hybrid covers
  • 4.3. Technical basis and design
    • 4.3.1. Compacted clay covers
    • 4.3.2. Composite covers
    • 4.3.3. Evapotranspiration covers
  • 4.4. Performance
    • 4.4.1. Compacted clay covers
    • 4.4.2. Composite covers
    • 4.4.3. Evapotranspiration cover
    • 4.4.4. Processes for change
  • 4.5. Monitoring final covers
• 5. VERTICAL CONTAINMENT BARRIERS
  • 5.1. Introduction
    • 5.1.1. Definition
    • 5.1.2. Applications of vertical containment barriers
    • 5.1.3. Vertical containment scenarios
  • 5.2. Types of vertical containment barrier
    • 5.2.1. Slurry cut-off walls
    • 5.2.2. Non-slurry cut-off walls
• 6. PERMEABLE REACTIVE BARRIERS
  • 6.1. Introduction
  • 6.2. Attenuation mechanisms and reactive media
    • 6.2.1. Attenuation mechanisms
    • 6.2.2. Reactive media
  • 6.3. Hydraulic and contaminant transport considerations
  • 6.4. Typical configurations
    • 6.4.1. Continuous permeable reactive barriers
    • 6.4.2. Funnel and gate system
    • 6.4.3. Multiple reactive zones in series
    • 6.4.4. Other configurations of permeable reactive barriers
  • 6.5. Methods of installation
    • 6.5.1. Driving and pulling
    • 6.5.2. Biopolymer slurry
    • 6.5.3. One-pass trencher
  • 6.6. Site characterization
    • 6.6.1. Hydrogeological characterization
    • 6.6.2. Contaminant characterization
    • 6.6.3. Geochemical characterization
    • 6.6.4. Microbial characterization
  • 6.7. Treatability studies
    • 6.7.1. Laboratory scale studies
    • 6.7.2. Field scale studies
  • 6.8. Potential performance issues
  • 6.9. Quality assurance and monitoring
  • 6.10. Other considerations
  • 6.11. Case studies
    • 6.11.1. Mill tailings site in Monticello, Utah
    • 6.11.2. Spent radioactive fuel processing plant, West Valley, New York
• REFERENCES
• ABBREVIATIONS
• GLOSSARY
• CONTRIBUTORS TO DRAFTING AND REVIEW