Influence of Soil Capping Depth on Water Dynamics in Phosphogypsum Stack Reclamation

• Author / Creator

  Christensen, Andre Forrest

• The influence of capping soil depth on water dynamics was investigated at a decommissioned phosphogypsum (PG) stack in Fort Saskatchewan, Alberta. PG is the a by-product in phosphoric acid production, a necessary component of phosphorus fertilizer. Currently, there are no environmental regulations governing the depth of capping soil required for PG stack reclamation. Time Domain Reflectometry (TDR), MPS-1 matric potential sensors and conservative tracer application were used to assess water balance across capping soil depths. Results from the varying experiments indicated that an increase in capping soil depth contributed to greater infiltration of spring snowmelt water resulting in deeper penetration of the advective water front into the reclaimed system. Percolation estimates for capping soil depths < 46 cm were <3% of annual precipitation; however, the temporal variation in downward flux estimates suggest spring snowmelt is the dominant event contributing to percolation.

• Subjects / Keywords

  • Capping Depth
  • Phosphogypsum
  • TDR
  • Water Balance
  • Soil Depth
  • Reclamation
  • PG Stack
  • ET Cover System
  • Percolation

• Graduation date

  Fall 2013

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3MK65H49

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.