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Boojum Research LTD - 25 years of Ecological Engineering

The role of Phosphate and Phosphate mining wastes in controlling ARD and AMD. Is it a chemical or biological role or is it both ?. Invited by West Virginia Mine Drainage Task Force Symposium Morgantown , March 2011 M. Kalin and W. N. Wheeler Boojum Research Ltd Toronto, Canada.

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Boojum Research LTD - 25 years of Ecological Engineering

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  1. The role of Phosphate and Phosphate mining wastes in controlling ARD and AMD. Is it a chemical or biological role or is it both ? Invited by West Virginia Mine Drainage Task Force Symposium Morgantown , March 2011 M. Kalin and W. N. Wheeler Boojum Research Ltd Toronto, Canada Boojum Research LTD - 25 years of Ecological Engineering

  2. Margarete Kalin/Boojum Research LTD • President and founder of Boojum Research LTD • Adjunct professor at U of Toronto, Ryerson University, U of Windsor, Queen’s Univeristy , Kingston • QEP with the Institute of Environmental Practice and Senior Ecologist with the American Ecological Society. • has written and presented more than 100 scientific papers, many book chapters and more than 100 technical reports • has applied the technology to effluent streams from coal, uranium, base metal and precious metals in North and South America as well as Europe. • RECIPIENT OF THE: • Noranda Award for Outstanding Achievement in the Field of Land Reclamation • Teck-Cominco Environmental Award • Distinguished Lecturer for the Canadian Institute of Mining. Boojum Research LTD - 25 years of Ecological Engineering

  3. No patents – Natural processes : Virtual Library http://biblio.laurentian.ca/boojum Company is 29 years old, with contracts worldwide. Canadian contracts only shown

  4. ECOLOGICAL ENGINEERING aims to practically and beneficially apply knowledge of how ecological systems operate on the mineral and rocks surfaces within these landforms • it utilizes the dynamics of well-adapted organisms within • MWWMA – no extra space needed • identifies those factors blocking the way to ecosystem growth • targets those locations within the MWWMA (sediment, rock surfaces or the AMD water) with applications of essential elements to promote growth (e.g. organic carbon, phosphate etc.) Boojum Research LTD - 25 years of Ecological Engineering

  5. These ecosystems are living landforms – they change with time 1919 1838 • Harder • microbial iron oxidation and precipitation in iron sedimentary deposits. • Ehrenberg • Gallionellaferrugineawith ochreous deposits of bog iron. 1887 Winogradsky Beggiatoa oxidation H2S to elemental sulfur; Leptothrix ochracea oxidation of FeCO3 to ferric oxid Geomicrobiology Microbial Biogeochemistry • Stutzer (1911) • Vernadsky (1908-1922) Microbial Ecology Geomicrobiology has a long history- and they dominate the MWWMA ecosystem

  6. Mineral Surfaces: The Site of the Problem and the Solution • Oxidation of sulphide particles in tailings, waste-rock piles, underground mine workings and open pit walls • Limited by the transport of oxygen • Convection, advection or diffusion to the mineral surface • Bacterial biofilm activity – BOTH OXIDATIVE AND REDUCTIVE – CHANGE THE HABITAT / ENVIRONMENT

  7. Scale diagram of typical bacteria size compared to the surface roughness Nutrients need to be added, NOT to the water, BUT to the rock surfaces and it has to stick to the rock in the oxidation pit

  8. Members of this Task force did leading work with tests of phosphate material

  9. Results from 5 Soxhlet leaching cycles – Appendix 1 My conclusion; Internal precipitation took place * Calculated average N=3 ** N= 24, each amendment all application rates N=3

  10. Field experiment • Fill #2 - 366 Tons shale/coal (parting) • Fill #6 - 367 Tons shale/coal l with 1.14 tons of apatite rock • Fill #7 - 368 Tons shale/coal with .55 tons of apatite rock Results were good – but did not make sense – so let‘s think what went wrong!

  11. Acid Mine drainage treatment: Phosphate Technology- the chemical Phosphate role • P and Fe cycling are closely linked • P concentrations (e.g. for organisms) are generally very low • P is sequestered as co-precipitates with Fe hydroxides (oxic conditions) • P forms metal salts (anoxic conditions) • P is bound by organics (e.g. humic substances in muskeg) • P may absorb to pyrite (source of AMD) surfaces and inhibit acid generation

  12. How did it start? A customer requested that something should be done to reduce oxidation rather than waiting for it occur! The Northern Miner Magazine Sept Oct. 1991 reported on the cessation leaching of Cu from a dump in B.C. Sample obtained in 1992 Boojum Research LTD - 25 years of Ecological Engineering

  13. The key questions are : How do we get NPR to the mineral surface or to the place where the AMD is generated? AND It has to be economic and practical It has to be suistainable – lasting for ever It has to be general – i.e. work in all types of wastes

  14. Relating the Scale of the Observations Phosphate Rock Waste Rock NPR Code 48 4 mm to < 0.04 mm 150 mm

  15. Boojum Research LTD - 25 years of Ecological Engineering

  16. B- zone waste rock pile in distance with muskeg area in front B-zone waste rock pile Boojum Research LTD - 25 years of Ecological Engineering

  17. Distribution of measured elements comprising 10% of a Waste Rock Pile B-zone waste rock pile As (0.07%) S (0.29%) Fe (10%) Boojum Research LTD - 25 years of Ecological Engineering

  18. We had to work in the field first – it has to work there, so we set up large field tests with Texas Gulf Natural Phosphate Rock – Train cars full of the stuff came to Northern Ontario and Quebec • In uranium tailings • In phyrrotite tailings ( Cu , Ni ) • In coal, coarse waste rock • in polymetallic concentate spills • In sulphidic waste rock ( Cu , Zn )

  19. Autopsy section overview Piles 1 to 4 Lime compacted etc Pile 5 NPR

  20. Tailings Surface Cover Development through Integration of Reactive Phosphate and Organic Matter (PHITO) Boojum Research LTD - 25 years of Ecological Engineering

  21. integrate nutrients, precipitation agents and NPR below the roots, then grow organics Boojum Research LTD - 25 years of Ecological Engineering

  22. 1995 Stanrock: Horse Manure and Natural Phosphate Rock Heterotroph Oxygen Requirements Heterotrophs counted fresh tailings: 107/g Populations oxygen requirement: 175µL/g Oxygen present in fresh tailings: < 20 µL/g Boojum Research LTD - 25 years of Ecological Engineering

  23. Only practical long term tests in mining wastes in the field can provide evidence of the validity of the assumptions • Tests NPR additions to tailings and conc. spill • 2- 85 % sulphide • left in field 3.2-3.7 years • monitor the pore water metal acidity • TAILINGS AREA – • Inco: 2700m2; • Stanrock:432 m2 • Test NPR additions to waste rock • 4-15 % sulphide • left outdoors 2.7 years • monitor the effluent metal acidity • Monitoring 1.8 Boojum Research LTD - 25 years of Ecological Engineering

  24. Results of the waste rock drums Boojum Research LTD - 25 years of Ecological Engineering

  25. pH profile for low pyrite Stable layer Unstable layer no matter what amount of pyrite – acid rock drainage is with you ! Boojum Research LTD - 25 years of Ecological Engineering

  26. If sulphide oxidation can be reduced - the process has to be similar in a large variety of mining wastes: Pore water results : Control NO NPR and NPR additions

  27. OXIDATION RATES Williamson and Rumstidt . 1994 r = 10-19.71 (±0.86). Eh12.93(±1.04). pH1.0(±0.29) (1) log r =-19.71(±0.86) + 12.93(±1.04)log(Eh) +1.0(±0.29)log(pH) Boojum Research LTD - 25 years of Ecological Engineering

  28. The reactant: Phosphate mining wastes or Natural Phosphate Rock • Un-economic for fertilizer production • a sedimentary deposit N. Carolina – Sea shells –Shark teeth (organophosphate) • grain size 4cm to < 0.04 mm • NPR contains 8-12 % P and 20-35 % Ca (as CaCO3) 16x

  29. Taylor mesh conversion and size description for the NPR Code 48 particles

  30. NPR is acid-soluble and provides all the nutrients needed for microbial growth It needs to be in particulate form on the mineral surface to change the environment We suspect the fine particles made it to the mineral surface We dissolved NPR in 0.1N sulphuric acid and only a fraction of it dissolved WE HAD THE BIOLOGICAL ROLE OF NPR! - MACRONUTRIENTS P (nucleic acids synthesis, ATP), K (enzymes activation), Ca (cells walls and endospores), MICRONUTRIENTS Fe (electron transport systems), Mn, Cu, Ni, Mo, Co and Zn (components of protein complexes and enzyme activators) Source :Chapelle, F; (1993 “Ground-Water Microbiology & Geochemistry” John Wiley & Sons, Inc)

  31. Scanning Electron Microscopy of Waste Rock Surface (1st Observation) 1995 Boojum Research LTD - 25 years of Ecological Engineering

  32. 2007 2009 After 3 years of outdoor exposure and 11 years of storage Fe Au S P AMIRA P933 Report Boojum Researchand U of Toronto (ongoingresearch) Boojum Research LTD - 25 years of Ecological Engineering Figure 8 - (A) A2 SEM/EDS 2009 (rock 2); (B) A3 SEM/EDS 2004 10

  33. Mineral Surfaces: The Site of the Problem and the Solution Waste rock with NPR Untreated waste rock Untreated waste rock Waste rock with NPR

  34. Bugs generallycauseonlytrouble, but whenfed, theyareheretohelp!A miningresearchgroupconfirmed the presence of a biofilm on rocksfromourexperiment in 2008. • It is presently being tested on other waste rock by the same group. • Do you want to reduce Acid Generation? • What are you waiting for. We are ready to work with you?

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