AMD Assessment Tool

The in-house developed tools and resources available for download from this page are provided for estimation purposes only. By downloading and using these tools the user acknowledges and understands the limitations and assumptions made and will not use the data as an alternative to conventional analytical procedures.

Earth Systems recommends that you contact a specialist in the relevant fields to confirm the estimations based on the output of these tools for process critical decisions.

AMDact: Acid and Metalliferous Drainage Assessment and Classification Tool

AMDact is a spreadsheet-based (Excelâ„¢) tool that uses the results from commonly performed static test work and geochemical analyses (e.g. NAPP, NAG, ANC, APP, MPA, Total Sulfur), to provide an assessment of the potential AMD risk. Samples are classified into one of 8 categories of potential to generate acid:

  • High Potential for Acid Generation
  • Moderate / High Potential for Acid Generation
  • Moderate Potential for Acid Generation
  • Low Potential for Acid Generation
  • Unlikely to be Acid Generating
  • Likely to be Acid Consuming
  • Inconsistent data (conflicting data)
  • Unclassifiable (insufficient data)

Assessments and classifications are based on threshold values developed over years of experience assessing ABA data.

Please be aware that this spreadsheet contains macros and these need to be enabled for AMDact to run.

There are currently two versions of AMDact. Version 1.0 performs assessment and classifications on single data samples, while Version 2.0 performs batch assessments on data tabulated within Excelâ„¢ spreadsheets.

AMDact is being finalised at present, and will be available in the near future. To receive further information on AMDact, please contact us at



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