O ne of our planet’s scarcest natural resources - safe, affordable and accessible water - is under threat from the coal industry. Vast amounts of freshwater are consumed and polluted during coal mining, transport and power generation. A typical 1000 MW coal plant in India uses enough water in one year to meet the basic water needs of nearly 700,000 people. Globally, coal plants consume about 8% of our total water demand. The coal industry’s thirst for water is particularly concerning given that some of the largest coal producing and consuming countries, including India, China, Australia and South Africa, already face water stress and are currently planning enormous build-outs of their coal industries. Coal is also a major polluter. Every stage of the coal life cycle pollutes water with heavy metals and other tox- ins at levels that significantly harm humans and wildlife. Exposure to this toxic stew has increased the rates of hu- man birth defects, disease and premature deaths. The im- pacts on wildlife are similar. Often colourless and out of public view, the contaminants from the coal life cycle are an invisible menace to our health and environment. Part 1: A Vast Consumer of Water MINING AND PREPARATION During mining operations, enormous amounts of ground- water are drained from aquifers so mining companies can access coal seams. Surface mines withdraw roughly 10,000 litres of groundwater per tonne of coal. Underground mines extract about 462 litres of groundwater per tonne of coal. The amount of dewatering varies greatly depending on the depth of the coal seam and local hydrology and geology. 1 A series of proposed mega-mines in Australia’s Galilee Basin is projected to extract 1.3 billion litres of water – over 2 1/2 times the amount of water in the Sydney Harbour. This extraction will drastically lower the water table, rendering local wells unusable and impacting nearby rivers. 2 After coal is mined, it is typically washed with water or chemicals to remove sulphur and other impurities. The US Department of Energy estimates that coal mining and washing in the US uses 260-980 million litres per day. 3 These amounts would satisfy the basic water needs of 5 to 20 million people (assuming 50 litres of water per person per day). The strain on water resources can be significant since mines are often located in arid regions. Mining also causes severe and long-term pollution of water resources, which can trigger water scarcity even in water-rich coun- tries. This is detailed in Part 2 of this factsheet. COAL FACTSHEET #3 The 2008 Kingston coal ash spill in Tennessee, USA dumped 3.8 billion litres of coal ash slurry into the Emory River. Photo: Dot Griffith INSATIABLE THIRST How Coal Consumes and Contaminates Our Water
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INSATIABLE THIRST · mostly coal, over agriculture. The intense financial burden triggered over 6000 farmer suicides. Despite this tragedy, 71 thermal plants, which would consume
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One of our planet’s scarcest natural resources - safe,
affordable and accessible water - is under threat from
the coal industry. Vast amounts of freshwater are
consumed and polluted during coal mining, transport and
power generation. A typical 1000 MW coal plant in India
uses enough water in one year to meet the basic water
needs of nearly 700,000 people. Globally, coal plants
consume about 8% of our total water demand. The coal
industry’s thirst for water is particularly concerning given
that some of the largest coal producing and consuming
countries, including India, China, Australia and South
Africa, already face water stress and are currently planning
enormous build-outs of their coal industries.
Coal is also a major polluter. Every stage of the coal life
cycle pollutes water with heavy metals and other tox-
ins at levels that significantly harm humans and wildlife.
Exposure to this toxic stew has increased the rates of hu-
man birth defects, disease and premature deaths. The im-
pacts on wildlife are similar. Often colourless and out of
public view, the contaminants from the coal life cycle are
an invisible menace to our health and environment.
Part 1: A Vast Consumer of Water
MINING AND PREPARATION
During mining operations, enormous amounts of ground-
water are drained from aquifers so mining companies can
litres of groundwater per tonne of coal. Underground mines
extract about 462 litres of groundwater per tonne of coal.
The amount of dewatering varies greatly depending on the
depth of the coal seam and local hydrology and geology.1 A
series of proposed mega-mines in Australia’s Galilee Basin
is projected to extract 1.3 billion litres of water – over 2
1/2 times the amount of water in the Sydney Harbour. This
extraction will drastically lower the water table, rendering
local wells unusable and impacting nearby rivers.2
After coal is mined, it is typically washed with water or
chemicals to remove sulphur and other impurities. The
US Department of Energy estimates that coal mining and
washing in the US uses 260-980 million litres per day.3
These amounts would satisfy the basic water needs of 5 to
20 million people (assuming 50 litres of water per person
per day). The strain on water resources can be significant
since mines are often located in arid regions. Mining also
causes severe and long-term pollution of water resources,
which can trigger water scarcity even in water-rich coun-
tries. This is detailed in Part 2 of this factsheet.
COAL FACTSHEET #3
The 2008 Kingston coal ash spill in Tennessee, USA dumped 3.8 billion litres of coal ash slurry into the Emory River. Photo: Dot Griffith
INSATIABLE THIRSTHow Coal Consumes and Contaminates Our Water
2 | C O A L A N D W A T E R F A C T S H E E T
THIRSTY COOLING SYSTEMS
The amount of water withdrawn from freshwater sources
and consumed by coal plants varies significantly depend-
ing on the type of cooling system used and the location of coal plants. Coal plants with once-through cooling sys-
tems withdraw tremendous amounts of water with disas-
trous impacts to aquatic life. The process of sucking in
vast amounts of water destroys an estimated 2 billion fish,
crabs and shrimp and 528 billion fish eggs and larvae each
year in the US as aquatic life is rammed against screens or
sucked into cooling systems.
While most of the water withdrawn is discharged back into
the original water sources, it is usually discharged at tem-
peratures 5.6-11°C hotter than when it was withdrawn. This
“thermal water” kills aquatic life and ecosystems, which
are extremely sensitive to small variations in temperature
change.5
Coal plants with closed-loop or recirculating cooling sys-
tems withdraw far less, but consume more, water than
plants with once-through cooling systems. These systems
usually use large cooling towers to let ambient air cool
the water. However, millions of litres of water can be lost
through evaporation and must be replaced.
Less than six percent of coal plants worldwide have dry
cooling systems, using air instead of water for cooling.
These power plants use 75% less water than plants with
recirculating cooling systems. However, dry cooling sys-
tems are expensive and energy-intensive. Power plants
with dry cooling must burn more coal for operation, de-
creasing their efficiency and increasing CO2 emissions by
up to six percent.6
ESCALATING WATER CONFLICTS
Situating coal mines and power plants in arid regions
around the world has sparked serious conflicts over water.
From 2001-2010, farmers in the Vidarbha region of central
India fell deeply into debt as the government liberalised
COMBUSTION
Coal-fired power plants consume the vast majority of water
used by the coal industry. Plants built inland require even
larger amounts of freshwater. Coal plants are increasing
the strain on freshwater resources at a time when climate
change is already starting to affect water supplies around
the world.
During the combustion process, coal is burned to boil wa-
ter and convert it into steam. The steam is used to turn
turbines, which power generators to produce electricity.
Different types of cooling systems are used to cool the
steam and condense it back into water. Almost all of the
water consumed by coal-fired power plants is used for
cooling systems.
Consumption vs. Withdrawal
To understand how coal plants use water,
it is important to distinguish between the
consumption and withdrawal of water. A typical
500 MW coal plant withdraws an Olympic-sized
swimming pool amount of water every 3.5
minutes.4 Water withdrawals for once-through
cooling are discharged back into the original
water source at higher temperatures. Water
consumed by coal plants is not returned to the
original source and is no longer available for
use as drinking water, for aquaculture or food
production by downstream communities. The
water may be contaminated by pollutants during
the combustion process and stored in ash ponds
or have evaporated during cooling processes.
Graph 1
Water Consumption for a 1000 MW Coal Plant
E N D C O A L | 3
its economy, scaled back support for small farmers and
prioritised the allocation of water for energy generation,
mostly coal, over agriculture. The intense financial burden
triggered over 6000 farmer suicides. Despite this tragedy,
71 thermal plants, which would consume two billion cubic
metres of water annually, are in various stages of approval
in Vidarbha.
India is steamrolling ahead with plans to construct hun-
dreds of coal plants despite projections that national water
demand will exceed supply within 30 years. The proposed
coal plants would consume 2500-2800 million cubic me-
ters of water per year.8 This would meet the basic water
needs of people living in India’s six largest cities – Mumbai,
Delhi, Bangalore, Hyderabad, Ahmedabad and Chennai (as-
suming 135 litres of water per day for urban dwellers).
The Chinese government plans to build 14 large-scale
coal mining bases and 16 new coal power generation bas-
es, predominately in western provinces, despite projec-
tions that China will face serious water scarcity by 2030.
Greenpeace estimates that these coal power bases will
consume 10 billion m3 of water annually (or roughly 1/6
of the annual volume of the Yellow River). Currently, water
resources per capita in these parched areas are only 1/10th
of the national average. Coal development would con-
sume a significant amount of water that is now allocated
for drinking, agriculture and wildlife.
In South Africa, coal expansion will exacerbate problems
with water scarcity. There is already a projected 17% gap
between water supply and demand. With 13 new coal
plants proposed, this will only worsen the situation. Coal
mining expansion is also water-intensive and will pollute
scarce fresh water supplies.9 Coal expansion in the pris-
tine, water-sensitive area of the Waterberg, in the north of
the country, is a massive threat as the water is guaranteed
for use by the coal industry, with no assurances for other
uses such as agriculture.
The siting of coal operations in regions of water scarci-
ty can affect their economic viability. If coal plants do not
have enough water to operate, they can be forced to shut
down. Hot weather may also warm water supplies used for
cooling, reducing the electricity production of coal plants
when it is needed most. These declines in production can
cut into revenues and make it difficult for companies to
service their debt.
(That’s enough to fill
over 12,000 Olympic swimming pools.)
The Tradeoffs of Coal Generation
Irrigation: 7,000 hectares
of agricultural land
1000 MW Coal Plant in India:
30-35 million cubic metres of water
equal to equal to
Basic Water Needs:670,000 urban
residents
4 | C O A L A N D W A T E R F A C T S H E E T
PART 2: How The Coal Life Cycle Pollutes Our Water
MINING
Surface mining dramatically alters natural water flow, in-
creasing flooding and jeopardising the safety of down-
stream communities. When open pit mines are construct-
ed, trees and other vegetation are cleared from large
tracts of land. Enormous amounts of earth are excavated
and piled in mounds next to mines. When it rains, ero-
sion clogs and pollutes
streams, wetlands and
rivers with tonnes of
sediment. Rivers can
become so choked
with sediment that they
can no longer be used
for fishing or transport.
An estimated 3840 km
of streams have been
buried by mountaintop
removal mining in the
Appalachia region of
the United States. The
effects of these valley
fills are irreversible.
Communities living
near mountaintop removal mining have suffered from in-
creased rates of lung cancer and heart, respiratory and
kidney disease due to their exposure to contaminated
water. Researchers found that 4432 people in this region
died prematurely from 1999-2005,
largely due to drinking contaminat-
ed water.10 Communities also expe-
rienced a 26 percent higher rate of
birth defects.11
Acid mine drainage is one of the most
serious impacts of coal mining. When
water interacts with rock exposed
by mining, naturally occurring heavy
metals such as aluminium, arsenic
and mercury are released into the en-
vironment. Acid mine drainage con-
taminates ground and surface water,
destroying aquatic ecosystems and
water supplies that communities depend on for drinking
and agriculture. These impacts can occur long after a mine
has been abandoned, and perhaps indefinitely.
A South African Water Ministry official publicly called acid
mine drainage “the greatest environmental challenge
ever.”12 South Africa has nearly 6000 abandoned mines.
Some estimate that nearly 200 million litres of acid mine
drainage per day threaten to pollute the Vaal River basin.13
Since the impacts of acid mine drainage occur long after
a mine has been abandoned, the liability and high clean-
up costs typically fall on local governments and taxpayers.
PREPARATION
After it is mined, coal is typically washed with water or oth-
er chemicals to remove impurities such as sulphur, ash and
rock. This process requires large amounts of water and
can strain groundwater aquifers. The resulting wastewater
is stored in slurry ponds. Some slurry pond dams are larg-
er than the Hoover Dam, storing billions of litres of highly
toxic wastewater.14 Coal slurry contains high quantities of
heavy metals and organic compounds, which can cause
cancer and harm the development of foetuses. Most slurry
ponds are unlined, allowing chemicals to leach into ground
and surface water.
Dams that impound slurry ponds are often built quickly
without adequate protections to ensure their safety and
structural integrity. When coal slurry dams fail, they can
spill millions of litres of toxic coal sludge, poisoning land
and contaminating rivers and streams. In October 2013,
an earthen dam broke, releasing 670 million litres of coal
slurry into tributaries of Canada’s Athabasca River. The
spill contained high concentrations of arsenic, cadmium,
mercury and lead, forcing the government to warn com-
munities not to use the river water until the slurry passed
downstream.15
TRANSPORT
BNSF Railway estimates that almost
300 kilograms of coal dust can escape
from each car in a loaded coal train
over a 600-kilometre journey. The coal
dust contaminates air and can lead to
black lung disease in humans. Coal
dust can also contaminate waterways
during rail transport, and through leaks
in damaged coal barges and during the
loading and unloading of barges.
COMBUSTION
Coal-fired power plants are the largest source of tox-
ic water pollution in the US, considering the toxicity of
the pollutants emitted. Wastewater from coal plants con-
tains a number of heavy metals and other toxins, which
harm and kill aquatic life and contaminate drinking water
supplies.16
Coal plants in the
US generate 127
million metric tonnes
of waste annually
– enough to fill a
football stadium
over 60 times.
Acid mine drainage destroys aquatic
ecosystems and contaminates water
supplies
E N D C O A L | 5
Coal plants generate millions of tonnes of heavy-metal
contaminated waste each year. This waste is laced with
arsenic, boron, cadmium, lead, mercury, selenium and
other heavy metals. Coal combustion waste is usual-
ly stored in dry landfills or mixed with water and stored
in unlined pits impounded by earthen dams. The use of
unlined pits increases the risk of pollutants leaching into
surface and groundwater and contaminating drinking wa-
ter supplies.
Dry storage is a better alternative to wet storage. In dry
storage the ash is put into a big landfill. The site must be
covered in order to minimise the risk of toxic dust blowing
off and water contamination from rainwater mixing with the
coal ash. If the bottom of the landfill is not lined with strong
impervious material, heavy metals are likely to leach into
the groundwater.
Air pollution control systems significantly increase the
amount of wastewater generated by coal plants by trans-
ferring pollutants from the air to water. This wastewater
often contaminates groundwater and surface water with
heavy metals at concentrations that harm wildlife and hu-
man health.17
ASH POND
How a Coal Plant Pollutes Water
ASH LANDFILL
Water withdrawals for cooling systems can cause water scarcity
and kill aquatic life.
Thermal water releases kill aquatic life.
Wet ash from boiler and air pollution control filters.
Ash pond spills harm people and destroy ecosystems
Leaching of heavy metals and other toxics pollute water and increase rates of cancer,
birth defects and neurological damage.
If no air pollution controls, sulphur dioxide emissions lead to acid rain, harming plants and wildlife. Mercury
emissions contaminate water, harming wildlife and human foetuses.
6 | C O A L A N D W A T E R F A C T S H E E T
IMPACTS OF COAL COMBUSTION WASTE
The toxins contained in coal combustion waste can injure
all of the major human organ systems, harm the develop-
ment of foetuses and children, cause cancer, and increase
mortality. In the US, toxics have leached from coal ash
waste and contaminated drinking water in over 100 com-
munities. The US Environmental Protection Agency (EPA)
found that, in some cases, the level of toxics leaching from
coal ash is hundreds to thousands of times greater than
federal drinking water standards. The agency also esti-
mates that people living within one mile of an unlined coal
ash pond have a 1 in 50 risk of getting cancer from drinking
water from contaminated wells. This is over 2,000 times
higher than what the EPA considers acceptable.
The impact of coal pollution on aquatic biodiversity has
been severe. Coal ash pollution has been documented to
cause deformities in fish and amphibians, reduce repro-
ductive rates and wipe out entire populations. Coal com-
bustion waste has caused an estimated US$2.32 billion in
damages to fish and wildlife in the US. Highly toxic seleni-
um is largely responsible for the damages.
The most dramatic impact of coal ash ponds occurs when
they fail. The largest catastrophic failure of a US coal
ash pond dam occurred in December 2008 in Kingston,
Tennessee, dumping nearly 3.8 billion litres of coal ash
slurry into the Emory River. Homes were destroyed and
families were relocated as their lands were smothered
with a toxic sludge. The political power of the coal indus-
try thwarted attempts to regulate coal combustion waste
until recently. 18
MERCURY
Burning coal releases toxic mercury into the air that then
rains down into rivers and streams. This poison then accu-
mulates in the food chain, eventually making its way into
our bodies when we eat contaminated fish. Mercury is a
powerful neurotoxin that can damage the brain and ner-
vous system. Mercury is of special concern to women who
are pregnant or thinking of becoming pregnant, since ex-
posure to mercury can cause developmental problems,
learning disabilities, and delayed onset of walking and
talking in babies and infants.
ENDNOTES
1 J Meldrum et al. 2013. “Life cycle water use for electricity generation: a review and harmonization of literature estimates,” Environmental Research Letters, 8: 015031.
2 “Draining the Life-blood: Groundwater Impacts of Coal Mining in the Galilee Basin,” Hydrocology Environmental Consulting, 23 September 2013, p. 5.
3 US Department of Energy (DOE). 2006. “Energy Demands on Water Resources: Report to Congress on the Interdependency of Energy and Water.” Washington, DC, p. 20.
4 “Coal Impacts on Water,” Greenpeace, 21 March 2014, http://www.greenpeace.org/international/en/campaigns/climate-change/coal/Water-impacts/
5 “Treading Water: How States Can Minimize the Impact of Power Plants on Aquatic Life,” Grace Communications Foundation, Sierra Club, Riverkeeper, Waterkeeper Alliance and River Network, 2013, pp. 4-5.
6 Union of Concerned Scientists website, “How It Works: Water for Power Plant Cooling,” http://www.ucsusa.org/clean_energy/our-energy-choices/energy-and-water-use/water-energy-electricity-cooling-power-plant.html.
7 Grace Boyle, Jai Krishna R, Lauri Myllyvirta and Owen Pascoe. “Endangered Waters: Impacts of coal-fired power plants on water supply,” Greenpeace India Society, August 2012, p. 5.
8 Boyle et al (2012), p. 3. 9 Melita Steele. “Water Hungry Coal: Burning South Africa’s Water to Produce
Electricity,” Greenpeace Africa, 2012, p. 4.10 Michael Hendryx and Melissa Ahern. Mortality in Appalachian coal mining regions:
the value of statistical life lost. Public Health Reports 2009; 124(4): 541–550.11 Melissa M. Ahern, Michael Hendryx, Jamison Conley, Evan Fedorko, Alan Ducatman
and Keith J. Zullig. The association between mountaintop mining and birth defects among live births in central Appalachia, 1996–2003. Environmental Research, August 2011; 111(6): 838–846.
Brushy_Fork_coal_sludge_impoundment15 “Cleanup of coal slurry spill into Athabasca ordered by province,” The Canadian
Press, November 19, 2013.16 “The unquenchable thirst of an expanding coal industry,” The Guardian, April 1, 2014.17 Steele (2012), p. 14.18 Gottlieb (2010), pp. vi-20.