Download Mining and the Environment

Mining and the
Environment
Questions for Today
► What
is ore and what are examples of
useful ores extracted from the crust?
► What are the different ways we extract ore?
► How does mining harm the environment?
► What are some laws that regulate mining
and reclamation?
Nonrenewable mineral resources
► Mineral
Resources:
 A concentration of naturally occurring material
from the earth’s crust that can be extracted and
processed into useful products.
►Fossil
Fuels
►Metallic Minerals
►Nonmetallic Minerals
Nonrenewable Mineral Resources
► Ores:
 A rock that contains a large enough
concentration of a particular mineral to be
profitable
 Two types:
►High-Grade
►Low-Grade
Valuable Minerals and Ore
► Metallic
Minerals
 Aluminum
 Steel
► An
alloy of Iron with concentrations of Manganese, Cobalt,
Molybdenum, and Chromium
 Copper
 Platinum
 Gold
► Nonmetallic
Minerals
 Sand
 Limestone
 Phosphate salts
Methods of Mineral Removal
► Two
types of Methods:
 Surface Mining
►When
gigantic mechanized equipment separate the
overburden, rocks and soil covering the ore, from the
ore.
 Subsurface Mining
►When
machines and workers mine underground for
seams of ore or other nonrenewable resource.
Surface Mining
► Four




types of Surface Mining:
Open-pit mining
Strip Mining
Contour Mining
Mountain-top removal
Open Pit Mining
► In
Open Pit Mining, machines dig holes and
remove ores, sand, gravel, and stone.
Strip Mining
► When
mineral deposit lie close to earth’s
surface, the most economical and useful
extraction method is Strip Mining.
► Two Types:
 Area Strip Mining
 Contour Strip Mining
Strip Mining
► Area
Strip Mining
 Used when the terrain is flat
 Each new cut is parallel to the previous one.
► Contour
Strip Mining
 Use on hilly or mountainous terrain.
 Overburden from each new terrace is dumped
onto the one below.
Mountaintop Removal
► The
most drastic type of extraction method.
► Uses dynamite to break apart hard rock to
expose the valuable ore beneath.
► Used primarily in the Appalachian
Mountains.
Mining environmental Hazards
► Scarring
the Land
 Mining destroys land virtually permanently.
► Leaves
► Land
topsoil degraded and the area wasted
subsiding
 Usually found where subsurface mining takes place
 Wear the land literally caves in
► Cause
Water and Air pollution
 Release acids into the water supply and groundwater
Mining Impacts
► Metal
ores are
smelted or treated
with (potentially
toxic) chemicals to
extract the desired
metal.
Figure 15-15
Natural Capital Degradation
Extracting, Processing, and Using Nonrenewable Mineral and Energy
Resources
Steps
Environmental effects
Mining
Disturbed land; mining
accidents; health hazards,
mine waste dumping, oil
spills and blowouts; noise;
ugliness; heat
Exploration,
extraction
Processing
Use
Solid wastes; radioactive
material; air, water, and soil
pollution; noise; safety and
health hazards; ugliness;
heat
Transportation or
transmission to
individual user,
eventual use, and
discarding
Noise; ugliness; thermal
water pollution; pollution of
air, water, and soil; solid
and radioactive wastes;
safety and health hazards;
heat
Transportation,
purification,
manufacturing
Fig. 15-10, p. 344
Mining Laws
► U.S.
General Mining Law of 1872
 Encourages mineral exploration and the mining
of hard rock minerals on US public lands.
► Surface
of 1977
Mining Control and Reclamation Act
 Required Mining Companies to reclaim lands
destroyed by mining.