- Mining involves extracting valuable minerals from the earth through various surface and underground methods. Surface methods include strip mining, open-pit mining, mountaintop removal, and dredging. Underground methods involve excavating tunnels and shafts.
- The extraction process produces both ore and waste rock. Ore undergoes crushing, grinding, and separation processes like flotation and cyanidation to extract minerals.
- Mining has environmental impacts like flooding, erosion, water and air pollution, and wildlife habitat damage. Preventive measures include replanting vegetation and stabilizing slopes. The government regulates mining through agencies like MGB and EMB and laws like the Mining Act.
2. Learning Objectives
• Describe how ore minerals are mined
and processed for human use
• Cite ways to prevent or lessen the
environmental impact that result from
the exploitation, extraction, and use of
mineral resources
3. • Answer this question
Would you allow large scale
mining operation to operate in
your locality? Explain your answer.
4. Group Activity
• “Role Playing – MININANG BAYAN”
• Imagine yourself living in impacted mining
areas and conceptualize realistic scenario for
role playing.
- Class will be grouped into two.
- Each group is given 10 minutes to dramatize
the scenario(s).
5.
6. What is Mining?
• Is the extraction of valuable minerals or
other geologic materials from the earth
from an ore body, lode, vein, seam, reef
or placer deposits which form the
mineralized package of economic
interest to the miner.
8. Types of surface mining
1. Strip Mining – removing a long strip
of overlying soil and rock
practical when ore body is relatively
near the surface
coal and lignite
two forms: area stripping and
contour stripping
9.
10.
11. Types of surface mining
2. Open-pit mining – extracting
rock or minerals from the earth
through their removal from an
open pit or burrow
12.
13. Types of surface mining
3. Mountaintop removal – is a form of
coal mining that mines coal seams
beneath mountaintops by first
removing the mountaintop overlying
the coal seam.
explosive are used to break up rock
layers
critics: disastrous practice
14.
15. Types of surface mining
4. Dredging – method for placer
mining below the water table
mostly associated with gold mining
large scale : used floating dredge
(barge like vessel )
16.
17. Underground
2. Underground mining –
extracting minerals and ores that
are buried too far underground to
be mined using surface mining
methods.
Mining Methods
18.
19. • Adits - is an entrance to an underground mine
which is horizontal or nearly horizontal, by
which the mine can be entered, drained of
water, ventilated, and minerals extracted at
the lowest convenient level
20. • Shaft mining or shaft - refers to the method of
excavating a vertical or near-vertical tunnel
from the top down, where there is initially no
access to the bottom.
21. • Drift mining – involves cutting an opening
horizontally into the side of a mountain or
hillside to access a mineral seam
- creation of a drift, a tunnel dug and driven directly
along a horizontal path
24. Milling Process
• Materials extracted or “mined” are rocks
composed of both ore and waste material
• Extracted rocks undergo process of mineral
(e.g metal) separation and recovery
• Crushing and screening are the first stages of
controlled size reduction followed by grinding
where rocks are pulverized.
25. Milling or Recovery Processes
1. Heavy media separation – crushed rock are
submerged in liquid where the
heavier/denser minerals sink (separate from
lighter minerals)
27. 3. Floatation – powdered ore is placed
into an agitated frothy slurry where some
minerals and metals based on physical and
chemical properties may either sink to the
bottom or may stick to the bubbles and
rise to the top thus separating the minerals
and metals from waste
28.
29. 4. Cyanide heap leaching – used for low-grade
ore where the crushed rock is placed on a “leach
file” where cyanide solution is sprayed or dipped
on top of the file.
as the leach solution percolates down through
the rocks, the gold is dissolve into the solution
The solution is processed further to extract the
gold
41. Impact Preventive Measures
• Topsoil replacement using uncontaminated
soil
• Reintroduction of flora and fauna
• Neutralizing acidic waters
• Backfilling and sealing of abandoned
underground mines
• Stabilizing the slope to reduce erosion
42.
43.
44. Laws
• RA 7942 – The Philippine Mining Act
• EO 79 – People’s Small Scale Mining
Areas
45. Role of Government
• Mines and Geoscience Bureau (MGB)
– Undertake final evaluation of all mining
application, conduct audit of the disposition of
mineral lands and resources, and manage the
Mineral Rights Management System
• Environmental Management Bureau (EMB)
- Issued ECC and monitor its commitments and
compliances