1. Britannia Mine, ARD, and the Millennium Plug Project
Brennan Lang, John Meech, and Rimas Pakalnis
Centre for Environmental Research in Minerals, Metals, and Materials

2. 40 km from Vancouver
Britannia
Mine

3. Beautiful Howe Sound

4. Sea to Sky Highway

5. Britannia Beach Harbour

6. Britannia Beach - from the mill building

7. Britannia Valley

8. 300 Tonne Truck at the Museum

9. Inside the mine at Britannia

10. Mine History Britannia Mine operated between 1902-1963 by the
Britannia Mining and Smelting Co.
and between by
the Anaconda Mining Company
- 47 million tonnes of ore mined
- 150 km of underground development
- 5 open pits (glory holes)
Britannia Concentrator

11. Britannia Flood and Landslide - October 1921

12. Old Time Miners
– circa 1950s

13. Customs Shed at Britannia – 1940s

14. 1992 Flash Flood Debris

15. Cementation Launders – 4100 Level

16. Mill Building in 2002

17. Mill Building in 2010

18. View inside the Mill Building

19. Beaty Lundin Centre – Britannia Mining Museum

20. A New Museum is Born

21. Site Ownership (2001) Britannia Mines and Reclamation Ltd.
– owned mine and mineral claims, as well as residential
area north of Britannia Creek and “North Fan Area”
Britannia Beach Historical Society
– owned most of “South Fan Area”
Province of B.C.
– owned foreshore area between highway & Howe Sound

22. British Columbia Assets and Land Britannia Beach Historical Society
Map of the Fan Area
Howe
Sound
Britannia Mines and Reclamation Corporation
British Columbia Assets and Land
- a Crown Corporation
Britannia Beach Historical Society
- BC Museum of Mining
Housing Development

23. Responsibility
BMARC was the only organization to declare itself a Responsible Person under the Waste Management Act
Other Potentially Responsible Persons named as part of the Contaminated Sites process in 1999 were:
Private PRPs: Alcoa, Canzinco, Alumax Inc., Anaconda/Arco, Howmet Holdings Corporation, Arrowhead/Ivaco, Intalco Aluminum Corporation
Province of British Columbia
Government of Canada
Government indemnified companies in exchange for $30M

24. Site Ownership (2003)
Macdonald Development Corporation bought the mortgage and foreclosed on BMARC
– Macdonald retained ownership of the residential area
north of Britannia Creek and “North Fan Area”
– Macdonald sold remaining ~9,500 acres to the
Provincial Government

25. Reclamation Issues in 2001 Acid mine drainage from tunnels (620 m3/hr)
About 800 kg of Cu & Zn discharged per day
Over 13,000 tonnes of metal since closure
Groundwater contamination on the Fan
Potential impacts on aquatic life
Waste dumps and stockpiles
Tailings at bottom of Howe Sound
Sealing abandoned adits, demolition of derelict buildings (public safety issues)

26. Reclamation Issues in 2001 Acid mine drainage from tunnels (620 m3/hr)
About 800 kg of Cu & Zn discharged per day
Over 13,000 tonnes of metal since closure
Groundwater contamination on the Fan
Potential impacts on aquatic life
Waste dumps and stockpiles
Tailings at bottom of Howe Sound
Sealing abandoned adits, demolition of derelict buildings (public safety issues)
________________________________________________________
Concentration Annual
Metal ppm Tonnes tonnes
Aluminum ,000
Zinc ,525
Copper ,725
Iron ,350
Manganese
Cadmium
Cobalt
Total = ,194

27. Groundwater discharge
< 5% of the flow
2-3% of the copper
3-4% of the zinc
4100 Level effluent
50-80% of the flow
30-55% of the copper
60-75% of the zinc
2200 Level effluent
20-50% of the flow
45-70% of the copper
25-40% of the zinc
Plug the 2200 Adit
Build a
Treatment Plant
Reclaim pits
and waste dumps

28. Glory holes/pits at Britannia Mine

29. Open Pits and Glory Holes

30. Cutaway View of the Mine Workings

31. Water Quality in 1995

32. Water Quality Change in 2001
Discharge
2200 Level (m3/hr)
4100 Level (m3/hr)
Cu in 2200 Level (ppm)
Cu in 4100 Level (ppm) (26)
Zn in 2200 Level (ppm)
Zn in 4100 Level (ppm) (23)
Copper Reduction (%)
Zinc Reduction (%)

33. Discharge from 2200 Level prior to 2001

34. At the adit

35. A Synergistic Research Plan
UBC had need for a research facility to conduct test work into the design of bulkheads to seal tunnels
By placing this Lab at the 2200 level portal, two synergistic events occurred:
UBC installed its research lab at a full-scale site
Britannia Mines and Reclamation Corp. was able to comply with part of its Remediation Order
The most harmful ARD from Britannia could be mitigated
Britannia Mine closure plan would move closer to fulfillment

36. Jane Creek showing a “Yellow-Boy”

37. Sampling and Monitoring

38. In the 2200 Level Adit

39. Installing Grout Tubes

40. The Millennium Plug Built in much the same way as an earth dam
Impervious clay core
Layers of sand, gravel, cobble, rip rap
Resistant to acidic conditions
Cheaper to build
Uses locally available materials
Generates a “walk-away” solution

41. The Millennium Plug Research Station
Quartzite Rock/Sand
Coffer
Dam
Concrete
Plug
Contact
Grouting
Pressurized
Chamber
Bentonite/Sand Seal
Sand/Gravel Filters
Into the mine
Cobble/Rip Rap
Longitudinal Section
Throttled Pipeline
Pressurized Pipeline
Not to scale
4 m
25 m
ARD effluent is diverted back into the mine workings.
Pressurized chamber allows the Millennium Plug to be studied under pressure/seismic conditions up to 300 m of water head
Service pressure = 9 m, but concrete plug designed for 300 m
The Millennium Plug was to be left in place to "back-up" the concrete plug that will fail in years from attack by acidic water
(pH = )

43. The effluent was turned off at 3:30 pm on December 31st, 2001.
The Concrete Plug was poured on December 17th in a blinding snow storm over an 18 hour period.
A total of 16 cement trucks had to be pulled up to the 2200 Level using front-end loaders and a bulldozer.
The effluent was turned off at 3:30 pm on December 31st, 2001.

44. Results at Britannia Creek Bridge
Copper and Zinc down by 2 orders of magnitude
pH up by 2 units to virtually neutral

45. Some people like to drink the Britannia Creek water and it is now safe to do so, although like all natural water streams in the wild, it is not recommended without prior chemical treatment.

46. EPCOR Water Treatment Plant
HDS = High-Density Sludge
Started up December 2005
Capital Cost = ~ $12.0M
Operating Costs = ~ $ 1.5M

47. HDS Plant – Process Flow Diagram
Sludge/Lime
Mix Tank
Lime Reactor
Clarifier
Effluent Overflow
Sludge disposal
Sludge Recycle
Lime
Tank
Flocculants
Tanks
Recycle Water
Lime Paste
Acidic Feed Water
Air
This a simplified process flow diagram for the HDS process at Britannia Beach .
Starting on the left, lime slurry is combined with recycled sludge in a small mix tanks
This lime/sludge mixture overflows to a rapid mix tank where it combines with the acidic feed. Lime dosage to the lime/sludge mix tank is controlled by pH at the rapid mix tank overflow.
The rapid mix tank overflows to a lime reactor. Oxidation and precipitation reactions are carried out in this reactor. Iron and manganese are oxidized using air to assist the process by co-precipitating other elements as well such as arsenic.
Flocculant is added to the lime reactor O/F prior to flocculation in the clarifier feed-well .
The clarifier separates treated effluent from the sludge. The sludge is pumped back to the lime/sludge mix tank to complete the process.
Clarifier overflows to a recycle water tank (not shown), which provides water for flocculant dilution, flushing and dilution of the recycle and sludge transfer systems.
Excess sludge at a density of 20 to 25 wt% solids is sent for filtering to a cake that is about 35%solids (like toothpaste). 47

48. Permit Requirements Element Required Typical mg/L mg/L
Dissolved Cu ≤
Dissolved Zn ≤
Dissolved Cd ≤
Dissolved Fe ≤
Dissolved Al ≤
Dissolved Mn ≤
Total Suspended Solids ≤
pH to
95HR LC50 fish bioassay % (non-acutely toxic)

49. Sludge Disposal Sludge Disposal involves filtration
Pressure plate filters
Final water content = 60%solids (like toothpaste)
Material consists of colloidal particles (sub-micron)
All metals are present as hydroxides or hydrated sulfates
Cu and Zn contents are about 4-5% each
Crystalline Ettringite, Ca6Al2(SO4)3(OH)12·26 H2O ~ 35%
Calcite, CaCO3 (minor quantities of aragonite) ~ 15%
Gypsum, CaSO4·2H2O ~ 5%
Quartz, SiO2 ~ 5%
Amorphous Phases ~ 40% 49

50. Sludge Disposal Sludge Disposal involves filtration
Pressure plate filters
Final water content = 60%solids (like toothpaste)
Material consists of colloidal particles (sub-micron)
All metals are present as hydroxides or hydrated sulfates
Cu and Zn contents are about 4-5% each
Crystalline Ettringite, Ca6Al2(SO4)3(OH)12·26 H2O ~ 35%
Calcite, CaCO3 (minor quantities of aragonite) ~ 15%
Gypsum, CaSO4 .2H2O ~ 5%
Quartz, SiO2 ~ 5%
Amorphous Phases ~ 40%
Ettringite
Calcium sulfoaluminate is found in all Portland cement concretes and is commonly referenced in petrographic reports. Calcium sulfate sources i.e., gypsum, are added to Portland cement to prevent rapid setting and improve strength development. Sulfate is also present in supplementary cementitious materials and admixtures. All sulfate compounds react with calcium aluminate to form Ettringite within the first few hours after mixing with water. All sulfur is consumed to form Ettringite within 24 hours. 50

51. Crystalline etteringite
Ca6Al2(SO4)3(OH)12·26 H2O
(Ca(OH)2)6(Al2O3)(SO3)3·26 H2O
In Portland Cement:
Plates of calcium hydroxide
and
Needles of etteringite
(CaO)6(Al2O3)(SO3)3·32H2O

52. SPECIAL WASTE EXTRACTION PROCEDURE
BC SWEP Test
BRITISH COLUMBIA
SPECIAL WASTE EXTRACTION PROCEDURE
BC Waste Management Act
LEACHATE EXTRACTION PROCEDURE USING ACETIC ACID (pH 5.0) BC
SWEP Test
Link
Effluent toxicity testing - 100% survival of Rainbow Trout in 100% conc. effluent.

53. Sludge Disposal Sludge disposed in Jane Basin – cost = ~$40/tonne
Temporary holding site at 4100 Level
Campaign trucking to Jane Basin in summer months
Future options
Manufacture building cladding using sludge and pumice
Pumice is mined at Mt. Meager and crushed at Squamish
Can use low-temperature process with organic resins
Can use high-temperature process to harden into a ceramic
Examine opportunities to recover Cu and Zn
From the effluent prior to HDS
From the sludge by leaching 53

54. Pumice rock – extremely light

55. Brick Veneer Cladding - examples
NRC Process Evaluation -
Canyon Stone -

56. What is ARD and how do we deal with it?
Impact first reported in 1556 by Agricola in De Re Metallica
Yet the term Acid Rock Drainage wasn’t coined until 1970
Significant work by NRCan (MEND Program) and Canadian companies developed innovative techniques to handle this ubiquitous problem
ARD requires sulphides, water, and air (and bacteria)
Minerals are the source of sulphur and iron
Air is the source of oxygen
Water is the transfer medium for oxygen from air to rock
Bacteria catalyze the reaction of Fe+2 to Fe+3

57. How long does ARD last?
ROCK

58. How long does ARD last? - Forever! Corta Atalaya, Rio Tinto, Spain
- abandoned pyritic open pit
Rio Tinto in Spain – 2 millennium after
mining

59. Is it only Mining that causes ARD?
Blood Falls at Taylor Glacier, Antarctica

60. Acid Rock Drainage – Metal Leaching
ARD
Formed by atmospheric oxidation (i.e., by water, oxygen, and carbon dioxide) of common iron-sulphur minerals pyrite and pyrrhotite in presence of bacteria Thiobacillus ferrooxidans, T. acidophilus, and T. thiooxidans ML
Acid (H2SO4) leads to dissolution of metals and subsequent pollution of aquatic environments

61. Basic Chemistry of ARD (from FeS2)
Basic Issues behind the Chemistry:
Equilibrium of Ferrous-Ferric Ions
Presence of Bacteria (Thiobacillus ferrooxidans)
Must have an initial source of oxygen (i.e., air)
Must have a way to transfer electrons (i.e., water)

62. ARD Reactions Ferrous Sulphate formed by Abiotic Oxidation:
2FeS H2O + 7O2 = 2FeSO H2SO4
Bacterial Oxidation of Ferrous Sulphate (T. ferrooxidans):
4FeSO4 + O H2SO4 = 2Fe2(SO4) H2O
Ferric Sulphate is Reduced and Pyrite Oxidized by these Reactions:
Fe2(SO4)3 + FeS2 = 3FeSO S
2S + 6Fe2(SO4) H2O = 12FeSO H2SO4
Elemental Sulphur Oxidation (T. thiooxidans):
2S + 3O H2O = 2H2SO4
Acid dissolves metals into solution meaning ARD is virtually always accompanied by high metal levels discharged into the environment.

63. Bacteria are essential
Thiobacilli from bacterial generator (no flagella) - left (x 5,000)
- centre (x 20,000)
Thiobacilli grown on ferrous iron (flagella) - right (x 5,000)
Formation of Bio-films can lead to long delay in onset of ARD (7-10 years)
from Le Roux, N.W., et al., Bacterial Oxidation of Pyrite, Proc. 10th International Mineral Processing Congress, Institution of Mining and Metallurgy, London, )

64. Metal Leaching – Influence of ORP (Eh or REDOX)
Malouf, E.E. and Prater, J.D. (1961), Role of Bacteria in
the Alteration of Sulphide, J. Metals, NY, 13, p
Garrels, R.M. and Christ, C.L. (1965), Solutions, Minerals
and Equilibria, Harper & Row, New York,

65. Control of ARD
Removal of essential component (sulfide, air, or water):
Waste Segregation and Blending
Blend-in neutralizing potential (NP) rock to yield pH 7.0
Base additives
Add limestone to buffer acid reactions
Covers and caps
Water covers are the most effective
Soil, clay, and synthetic covers (geomembranes)
minimize water and air infiltration

66. Control of ARD
Removal of essential component (sulfide, air, or water):
Bactericides
Chemicals that reduce bacteria (T. ferrooxidans)
Effective in the short term, but costly
Collection and treatment of contaminants
Active or Passive treatment
Active treatment - high-density lime sludge
Passive treatment in constructed wetlands
Bioremediation (micro-organisms)
Remove metals directly
Introduce viruses against the bacteria

67. Factors affecting Soil Cover Performance
International Network for Acid Prevention, Evaluation of Long-term Performance of Dry Cover Systems, Final Report. O’Kane Consultants Inc., (Eds.), Report No

68. Geomembranes Plastics (polyethylene (PE) High density poly. (HDPE)
Chlorinated poly. (CPE)
Chloro-sulphonated poly.
(DuPont HYPALON)
polyvinyl chloride (PVC)
Low-density poly. (LLDPE)
Geosynthetic clay liners (GCL)
Geomembranes impregnated with bitumen
After Meer, S.R. and C.H. Benson, Hydraulic conductivity of geosynthetic clay liners exhumed from landfill final covers. J. Geotech. and Geoenviron. Eng., 133(5):

69. Passive Treatment Technologies
Name
Description
Function
Selected References
Aerobic wetlands
Shallow wetlands
Emergent vegetation
Fe and Mn oxidation, Co-precipitation of metals Sorption on Biomass
Eger and Wagner, 2003
USDA and EPA, 2000
Open limestone
channels
Acidic water flows over
limestone, or other alkali
Alkalinity addition
Al, Fe, Mn oxide precipitation
Ziemkewicz et al., 1997
Anoxic limestone
drains
Water flows through limestone channel under anoxic conditions
Alkali addition; Fe Precipitation; Limestone Armouring Prevention
Watzlaf et al., 2000
Anaerobic wetlands
Subsurface wetland, isolated from air by water or material
Alkali addition; Sulphate Reduction Precipitation of metal sulfides; Sorption on Vegetation
Brenner, 2001
Successive Alkalinity
Producing Systems
Vertical flow systems drain through limestone layers & anaerobic organic matter
Alkalinity addition; Sulphate Reduction
Metal Precipitation
Kepler and McCleary,1994
Zipper and Jage, 2001
Sulfate-Reducing
Bioreactors
Collected water in anoxic chamber containing organic matter and SRBs
Alkalinity addition; Sulphate Reduction Metal Precipitation
Gusek, 2002
Permeable Reactive
Barriers
Intercepted groundwater flows through permeable barrier containing reactive material
Alkalinity addition; Sulphate reduction
Metal Precipitation and Sorption
Benner et al., 1997
US DOE, 1998
Amendments
Materials added to ARD sources or holding areas
Alkalinity addition; Sulfate Reduction and Metal Precipitation; Sorption;
Chelation; Revegetation
Chaney et al., 2000

70. So Reduction Process Schematic
H2S
Nutrients
BIOREACTOR
(So Reduction)
Sulphur
Electron donor Cu
Precip Zn
CuS
ZnS
Treated
Water
Contaminated
Drainage
Metals, SO4
Soda Ash or Lime
BioteQ
After R.W. Lawrence, BioteQ

71. SRB Plant – Major Equipment
Copper Product
Zinc Product
ARD
Bioreactor So
e- donor
Lamellar
Clarifier
Filter Press
Gas-Liquid
Contactor
To Lime Plant
or Discharge
BioteQ
After R.W. Lawrence, BioteQ

72. (projected settling area
SRB Plant Layout: ~360m2
GAS-LIQUID
CONTACTOR
BIOREACTOR
1.8 m
LAMELLA CLARIFIER
(projected settling area
150 m2)
5.9 m
3.1 m
2.4 m
FILTER-PRESSES
0.8 m x 3 m W x L
REAGENT
PREP AREA
Cu -CONC
STORAGE
8 m
MCC
DOOR
TRUCK
Zn -CONC
7 m
BLOWERS
SCRUBBER
BioteQ
After R.W. Lawrence, BioteQ

73. Production Summary Flow Feed Water Discharge Water Cu Concentrate
14,880 m3/d – average over 12 months
Feed Water
[mg/L] 18.0 Cu, 20.0 Zn, 0.1 Cd
Discharge Water
[mg/L] 0.05 Cu, 0.01 Zn, Cd
Cu Concentrate
187.0 tonnes per year contained copper
51.1% Cu, 2.1% Zn, 0.24% Fe, 33.1% S
Zn Concentrate
185.5 tonnes per year contained zinc
52.4% Zn, 1.5% Cu, 0.3% Cd, 0.8% Fe, 27.1% S
Additional Benefits
Lime Savings
$64,000 per year (32%)
Sludge Reduction
tonnes per year (15-20%)

74. Commercial Scale Plants

75. Basic Reaction Chemistry of SRB Processing of ARD for Metal Recovery
Sulphate reduced by organic compounds:
SO4= + CH3COOH + 2 H+ = HS- + 2 HCO H+ 1.
Sulphide ions precipitate metal sulphides:
HS- + M2+ = MS↓ + H+ 2.
S= + M2+ → MS↓ 3.
Equilibrium of H2S
H2S(g) = H2S(s) = HS- + H+ = S= + 2H+ 4.

76. Some Links on Acid Rock Drainage
Natural ARD
Introduction to ARD – Chris Mills
Global ARD Guidelines – INAP
Mine Effluent Neutral Drainage Program - NRCan

77. The Stawamus Chief - Squamish