SUSTAINABLE DEVELOPMENT - Aims at meeting the needs of present generation without adversely affecting its availability for future

1. Author: Partha Das Sharma (B.Tech – Hons., in Mining Engineering)
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Website: http://miningandblasting.wordpress.com/

2. SUSTAINABLE DEVELOPMENT
Aims at meeting the needs of present
generation without adversely affecting its
availability for future
Rate of depletion of non-renewable
resources should be judicious
Minimum adverse impact to the
environment
Maintaining equilibrium in eco-system.
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3. SALIENT FEATURES OF MINING
PROSPECTING & EXPLORATION
MINE DEVELOPMENT
WASTE DISPOSAL
DRAINAGE
TRANSPORT
END USE OF MINERAL PRODUCED
BENIFICIATION PRACTICE
SITE SRVICES
ENVIRONMENTAL MANAGEMENT
POST MINING LAND USE
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4. PROSPECTING & EXPLORATION
It is the most important
exercise, to be carried out very
faithfully because entire fate of
future lies upon this
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5. PROSPECTING vs. EXPLORATION
Prospecting is pre- Exploration is a
mining stage dynamic process &
operation mainly continues during
confines to subsistence of mining
establishing sufficient period. It is expected
evidence of mineral it should lead ahead
occurrence in respect of mining operation
of shape, size, for consistent
quantity, quality & updating the mineral
economics reserve
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6. It also should include
Identification of various litho-units occurring
in & around the proposed mining site
Establishing sufficient evidence of mineral
occurrence in respect of shape, size,
quantity, quality & economics
Correct assessment of geo-technical
properties of rock mass including their toxic
values.
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7. CONCEPTUAL MINING PLAN
Long-term Perspective view of mining
Time frame for assessing the true potentiality
of area
Visualization and determination of ultimate pit
limit
Waste disposal management
Post-mining land use
Ensuing mining operation are part of it.
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8. MINE DEVELOPMENT
Mode of Mining
Selection of method
of mining
Mechanized
Semi-mechanized
Opencast
Manual
Underground
Conventional
Mixed
Non-conventional
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9. OPEN CAST MINING
Precise assessment of optimum stripping
ratio for amenability by open pit mining
Determination of ultimate pit limit precisely
in advance
Separate removal of top soil, mine-waste
Advance removal of waste to avoid any
possibility of interruption in work or ore
dilution/contamination
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10. OPEN CAST MINING continued….
Proper laying of mine faces for winning of
different grades simultaneously to ensure
judicious blending of ROM
Aiming to mine up to optimum depth
Minimum mineral loss / dilution
Safe, secure & energy saving haul road
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11. UNDERGROUND MINES
1. Selection & location proper mode of
entry & exit i.e.
Vertical shaft
Inclined Shaft
Decline/Ramp
Auxiliary/staple/ventilation shaft
System of winding & access
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12. UNDERGROUND MINES continued
2. Selection of proper method of work in
relation to-
Optimum recovery
Geotechnical properties of ore & wall rocks
Adequate size of openings, blocks, pillars
etc & long-term sustainability
Complete width of ore body is to be worked
Ensure least surface damage
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13. MINERAL CONSERVATION
Waste should not be allowed to mixed with
non-saleable fraction.
Ground selected for waste disposal is to be
proven for mineral occurrence and should be
away from ultimate pit limit.
Separate stacking of sub-grade mineral
Judicious blending by different combination
In case of underground mine, subgrade
mineral is to be brought to the surface.
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14. BENIFICIATION OPERATION
All attempts are to be made for up-
gradation of low-grade mineral to
make it saleable fraction.
Beneficiation Investigation are to be
carried out
Regular analysis of ‘feed’, ‘product’ &
‘tailings’
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15. PLANT & MACHINARY
Selection of matching
machinery to the mine design
parameters & local conditions.
Optimum utilization
Time & motion study
Least waiting/idle time
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16. PLANT & MACHINARY continue..
Energy saving & conformity to
emission standards
Attenuation of noise at the source
itself
Dust suppression at the source of
generation
Planned preventive maintenance
Minimum re-handling
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17. BLASTING
Proper Blast design
Optimum utilization of blast energy
Desired fragmentation
Neither under break nor over break
Least ground vibration
Least air blast
Least fly rock
Least nuisance attracting public annoyance
Regular scientific investigation
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18. SOLID WASTES GENERATED
MINE WASTES MILL/PLANT WASTE
Large in quantity Less in quantity
Mostly inert Can be toxic
Large in size- Solids Fine particles-Slurry
Represents in-situ Altered Product
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19. ENVIRONMENTAL PROBLEMS
Leaching & wash off - heavy metals & toxic
elements -acid mine drainage
Dust pollution with toxic metals
Phyto-accumulation of heavy metals
Effect on vegetation & aquatic eco-system,
Entry into food chain
Effect on landscape
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20. WASTE DUMP DESIGN
Height, area & shape with regard to the area
available, topography & vegetation.
Avoid Proliferation of dumps.
Surfaces should be stable & resist long term
erosion.
Peripheral dumping, with simultaneous
afforestation.
Toxic waste dumps to be contoured and/or
sealed to minimize water penetration.
Potentially acid forming material to be sealed
by inactive waste that has a buffering capacity.
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21. WASTE DUMP DESIGN
Construction of drainage to handle heavy
rainfalls.
Topsoil scraped out from dumpsite in advance,
to be preserved, spread over surface & re-
vegetated.
Provision of garland drains surrounding the
dumps
Provision of Retaining walls/Toe walls.
Completed overall out-slopes do not exceed 20
degree
Provision of benches/berms.
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22. DUMP INSTABILITIES
(Long-term instability)
REASON SOLUTION
Due to saturation Growth of
with water & permanent
reduction in vegetation over
strength of dump surface &
material due to establishment of
water action. proper drainage.
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23. DUMP INSTABILITIES
(short-term instability)
REASON SOLUTION
Benches, of heights not
Poor material
more than 10 to 15 m,
strength, improper with min. berm width of
heights & slope 4 m.
angles.
Berm to have gentle
Long unbroken slope, say 0.5%,
slopes produce rill & towards high-wall side,
gully erosion with toe wall along
periphery of dump.
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24. Estimated relationship between the angle of
dump slope and soil erosion & efficiency of re-
vegetation
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25. VARIOUS TYPE OF DUMPS
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26. Management of Waste Dumps
(Physical Stability)
ISSUES
Steep slopes
Unstable surfaces
Erosion
Drainage
Dust Generation
Hazardous waste Control
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27. Management of Waste Dumps
(Physical Stability)
Control Methods
Site selection
Peripheral dumping, Retaining walls/Toe walls
Internal drains & garland drain
Gentle slopes & heights
Berms, with rock-lined drains
Cover & secure containment of hazardous waste,
Cap with soil
Settling ponds
Vegetation along slopes
Green barriers
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28. Management of Waste Dumps
(Chemical Stability)
Issues
Metal leaching
Seepage
Acid drainage
Contaminants
Effects on surface and
groundwater
Dump design
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29. Management of Waste Dumps
(Chemical Stability)
Control Methods
Analyze the samples
Isolation of reactive material
No deterioration in groundwater
Cap/enclose toxic material with inert &
impervious material
Control surface drainage & runoff
Collect and treat effluent
Cap with topsoil & vegetate
Effective water management
Monitor
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30. Management of Waste Dumps
(Land-use)
Control Methods
Issues Marketing/reuse of waste
Productivity Back-filling
Visual impacts Avoid dump proliferation
Restore to original or Design for minimum area
accepted alternative use
Re-contour
Establish land drainage
Establish vegetation
Landscaping
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31. Management of Waste Dumps
(Biological Stability)
Issues
Control Methods
Re-vegetation
Soil Fertilization/stabilization
Bio-diversity Planting leguminous plants
Survival of vegetation Draught resistant species
Phyto-accumulation of Selection of Phyto-resistant
toxic & heavy metals species
Entry of toxic & heavy Successful re-vegetation with
indigenous plants
metals into food chain Protection for animal grazing
Development of self- Monitoring for soil quality
sustaining plant Congenial environment for
community wildlife, with fodder & water
Forestry
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32. TOP-SOIL MANAGEMENT
Recovery is essential for rehabilitation
work. Sooner it is reused the better the
results will be.
Soil Stacks:
Low heights,
Should not get washed off
Leguminous plants are to be cultivated
In areas of poor soils, nutrient levels is low Fertilizer
application is soil cheaper than soil stabilizers
Single application will suffice in all areas except those
prone to high soil leaching - eg over tailings
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33. TAILING IMPOUNDMENT
Design requirements of dam & impoundment:
Impoundment to be competent to support
Not to be located in recharge zone, establishing hydraulic
with aquifer
Relatively impervious, otherwise an impervious
layer/dyke to be provided at bottom
Foundation soil of the dam and the dam it self be
competent to support & relatively impervious, otherwise
internal drainage to be provided in side the dam
Dam should have stable slopes- downstream slopes 1:3
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34. Design requirements of dam &
impoundment
Adequate drainage features to be provided
As much as water must be re-cycled
Conduits from decant towers passing below the
dam be avoided
A floating or moveable pump hose located on
the shore is better for water reclamation
At each stage, dam raising should be fast to
stay ahead of the rising tailings in the pond.
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36. Management of Tailing Impoundment
(Physical Stability)
Control Methods
Site capacity & impervious
Issues
Dam erected by competent rock
Dam wall stability & foundation
Spillway/Adequate freeboard –1m
Dust generation
Decant towers or floating pump
Erosion & Sediment deposit
Diversion of runoff to out side
Dam drainage & Seepage
Stage-wise raising to be fast
Control on Phreatic line
Tailing disposal
Overtopping of dam
Downstream Construction
Earthquakes
Final re-profile, Instrumentation
Access and security
Cap with soil & vegetate
Plug intakes & decants
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37. Management of Tailing Impoundment
(Chemical Stability)
Control Methods
Issues Leaching tests
Changes in tailings Non-reactive material in dam
geochemistry wall
Metal leaching Impervious layers- seepage
Acid drainage Establish drainage within dam
Mill reagents Control reactions
Dam structure Divert run-off
Groundwater- seepage effect Collect and treat effluent
past the dam & from
impoundment base Acceptable water quality in
downstream
Surface water management
Monitor
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38. Management of Tailing Impoundment
(Land- use)
Control Methods
Issues
Re-contour to mach
Productivity surrounding landscape
Visual impacts Provide soil capping
Restore to accepted Provide sedimentation
alternative use tank
Establish vegetation
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39. Management of Tailing Impoundment
(Biological Stability)
Control Methods
Issues
Re-vegetation Soil stabilization
Bio-diversity Planting leguminous plants
Survival of vegetation Indigenous species
growth Draught resistant species
Phyto-accumulation of Selection of species resistant to
toxic & heavy metals phyto-accumulation &
concentration of toxic elements
Entry of toxic & heavy Protection of re-vegetated area
metals into food chain against animal grazing
Monitoring for soil quality & for
phyto-accumulation
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40. WATER QUALITY
Quantitative & Qualitative studies, for
Surface & Ground Water characteristics
Available Site Water Sources
Catchments area
Water Management & upstream pollution
sources
Maximum & Lean Rainfall
Runoff rate at Peak Rainfall
Potable Water Supply
Sources, Quality & Quantity
Domestic & Process Waste Water discharge
Discharge points, Quality & Quantity
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41. WATER BALANCE AT SITE
Lean season water availability
Source tapped with competing users (River,
Lake, Ground, Public supply)
Changes observed in quality & quantity of
ground water
Present recharging & extraction details
Quantum of surface waste water to be
released with treatment details
Quantum of quality of water in receiving
body, before & after disposal of waste
/effluent
Quantum of waste/effluent water released
on land & type of land 41

42. Water balance diagram
Schematic diagram linking up flow of
water to & from the facilities,
Showing water supply source (s),
Water discharge points),
Evaporation areas & potential seepage
points, with step wise indication of
flow rates, in cum/day & quality, into &
out of facility
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43. Management of Water Quality
(Physical Stability)
Control Methods
Issues
Remove/restore unwanted
Erosion, wash-off & structures, Fill in ditches
sediment deposit Plug intakes & decants
Blockage in natural flow Upgrade flood design
Sewage & effluent Reinstall pre-mining drainage
treatment plants & Dispose plants & plant
sludge sludge
Discharge of drainage Install check dams/settling
pond
Structural Safety & Develop re-charge
flood capacity wells/holes
Intrusion of sea water Re-vegetate
Water balance, Install pre-mining water
balance for mine area
recharge 43

44. Management of Water Quality
(Chemical Stability)
Control Methods
Issues Prevent/remove contamination
of surface &groundwater with:
-Acid drainage
Contamination of -Leaching of toxic metals
surface and /or Install new settling ponds
groundwater Erect stopping or flood the pit
Acid drainage Drainage - treat & discharge
Leaching of toxic metals Install barriers/grout curtains
Establish phyto-accumulant
vegetation
Monitor
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45. Management of Water Quality
(Land-use)
Control Methods
Issues
Avoid interruption of water
supply
Interruption of water Establish erosion-resistant
supply in catchment drainage
area Restore drainage patterns or
Productivity of land establish effective
drainage alternatives
Install retaining walls
Sediment deposition Stabilize and maintain dam
(Nalla sediments) or breach
Return to appropriate Establish vegetation
land use Establish effective
rehabilitation
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46. Management of Air Quality
(Physical & Chemical Stability & Land-use)
Control Methods
Cap toxic & hazardous waste
Issues Remove or prevent
Wind Erosion contamination
Effect on vegetation Land fill & capping
Pollution of air with toxic Establish vegetation
substance
Contamination of surface Develop thick green barriers
Productivity of land Monitor
Establish erosion-resistant
Structures
Return to appropriate land use
or establish alternatives
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47. Monitoring of Water & Air
Quality
To demonstrate remedial/ restoration
work is successful.
To meet closure objectives &
performance criteria.
To compare results with earlier
monitoring data.
Monitoring for dry season, as per
IBM/MoEF norms.
Climactic data also to be coupled
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48. RECLAMATION & REHABILITATION
Creation of adequate green belt in and
around mining lease area
It gives a green curtain is to be set against
all scars i.e. excavation, dumps etc and
improves aesthetic sense of the area
It effectively arrests all the dust generated
from mines
It effectively attenuate unpleasant noise
Lessens the adverse effect of green house
gas emission 48

49. RECLAMATION &
REHABILITATION continued….
Incase of availability of mine waste,
voids are to be filled back & efforts
are to be made to bring them near
original shape
Incase of partial availability of waste,
possibility of part reclamation is to be
thought. Remaining voids can be
converted as water reservoir
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50. RECLAMATION &
REHABILITATION continued….
Possibility of filling by fly ash or other
waste material available nearby is also to
be thought but a prior study thereof is also
to be undertaken for any apprehended
adverse impact on water regime
In case of shallow excavations, quarry floor
plantation is to be undertaken along with
adequate drainage arrangement
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51. RECLAMATION &
REHABILITATION continued….
Incase of arid regions, converting
the pits as water reservoir is best
post mining land use. But its slope
should be adequate & should also
act as shield against drowning.
Incase of hilly terrain dense
plantation is to be undertaken on
finalized bench.
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52. Conclusion:
Mankind should learn the correct way
of enjoying the natural wealth from
the Honeybee as they continue to
collect Honey from the flowers
without causing any detrimental
impact or deformation to the nature’s
beautiful gifts.
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