Chapter 14

Environmental tracers

Outline:

• Defn: a substance used to mark a pathway.
• Uses and examples of uses
• Accidental tracers
  • Contaminants- heavy metals, radioisotopes, organic compounds, trash, spills
  • Cosmogenic radionuclides- 10Be, 14C, 26Al, 32Si, 36Cl, 39Ar
  • Stable isotopes
  • Biological debris- pollen, seeds, insect parts, bones
  • Sediment types
• Deliberate tracers
  • Ionic solutions- bromides and chlorides
  • Fluorescent dyes- Rhodamine WT
  • Radioactive nuclides
  • Stable isotopes
  • Sediment particles

Textbook reading:

• p. 241-248 and p. 256-260 of Chapter 13

Other reading:

• p. 678-682 of Domenico, P. A. and Schwartz, F. W. 1990. Physical and Chemical Hydrogeology. John Wiley and Sons, New York.
• Here is a useful reference:
  • Smart, P.L. and Laidlaw, I.M.S. 1977. An evaluation of some fluorescent dyes for water tracing. Water Resources Research 13:1:15-33.

Related web links:

• Lawrence Livermore National Lab Groundwater Tracing
• Oak Ridge National Laboratory Hydrology Field Test Sites
• Explanation of Cosmogenic Radionuclides

Video Podcast: Environmental Tracers

This 42-minute presentation explains how deliberate and accidental materials released into natural waters can be used to reveal the mechanisms by which water moves around and transfers the materials it carries.

• 640 x 480 (480p) format that balances speed and quality. (416 MB file)
• 1920 x 1280 (HD) format that provides larges size and best quality. (3.1 GB file)

Last Chapter  :  Assignment 4