Confining Zone

{
  "id": "MLC-T-ENV-006139",
  "term": "Confining Zone",
  "field": "Environment",
  "definition": "1. A geological formation (or group or part of a formation) capable of limiting fluid movement out of an injection zone. The ideal confining zone has low permeability and sufficient thickness to prevent upward movement of injected waste.\n\n2. The confining zone means a geological formation, group of formations, or part of a formation that is capable of limiting fluid movement above an injection zone. It is composed of rock layers that are impermeable or distinctly less permeable than the injection zone beneath it. There may be multiple confining zones above an injection zone.\n\n3. Geological formation, group of formations, or part of a formation that is capable of limiting fluid movement above an injection zone.",
  "subject": "Land, waste and cleanup",
  "see_also": [
    "Caprock"
  ],
  "references": [
    "Underground Injection Control Glossary",
    "Underground Injection Control Terms",
    "40 CFR 146.3 (CFR 2018)"
  ],
  "url": "https://mlchart.com/terminology/environment/confining-zone/"
}