Download Water pollution, part I - University of South Alabama

WATER
Outline
• Water pollution enforcement (before test)
• Sources
–Categories of pollution (before test)
• Effects
–Result of pollution in water (after test)
Environmental Issue
• Problems that affect some part of the
Earth, usually a result of people or their
actions
– Water, air, soil, food, waste, plants
• Water as an environmental issue
– Quality – how clean is it?
– Quantity – how much is there?
Water pollution
• Pollutant: any waste discharged into
water, including materials, equipments,
rock, spoil, sewage, garbage, etc.
– Heated water above the temperature of the
receiving water also a pollutant
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Terminology
• Point source pollution: “any discernable,
confined, and discrete conveyance”, such
as pipes or man made ditches that
discharge pollutants into water
• Nonpoint source pollution: caused by
rainfall or snowmelt moving over and
through the ground.
– Includes atmospheric deposition –
contaminants carried by air
Nonpoint source pollution
4 categories of NPS pollution
1. Agriculture runoff
– Pesticides and fertilizers
– Example: cows produce 66lbs of manure/day
• Feedlots not necessarily required to control, treat,
or capture runoff
2. Urban runoff: streets, parking lots, golf
courses, gardens, industrial sites
3. Construction Sites: release vast amount of
sediments in water
4. Land disposal: waste, dumps, septic
systems
Cleaning up the waters
• 1899 Rivers and Harbors Act – navigable
waters
• 1948 Federal Water Pollution Control Act
– Control water pollution through state-led
efforts
– Enforcement left to governors (states)
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Events leading up to new regulation
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Cuyahoga River Fire (1969)
Santa Barbara, CA oil spill (1969)
EPA founded 1970
Earth Day 1970
Water Wasteland (Ralph Nadar) -1971
Cuyahoga River, 1936
State of water in early 1970s
• 1966-1968: 26 million fish killed in Florida
due to food-processing plant discharge
• 1969: Hudson River had 170x the safe level
of bacteria
• 1970: 30% of drinking water samples
exceeded recommended chemical limits
• 1971: 85+% swordfish contained mercury
exceeding safe limits
Clean Water Act - 1972
• Amendment to the Federal Water Pollution
Control act
• Changed in philosophy to “clean waters”
• Uniform technology-based standards
• Goals to eliminate pollution
• Protect fish, wildlife, and recreational use
• Shifted permitting and enforcement from
states to federal government - EPA
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NPDES and CWA additions
• National Pollutant Discharge Elimination
System (NPDES) – issues all permits for
discharges of allowable levels of pollutants
into waters
– Generally does not issue permit for discharges
into municipal water sewer system
• EPA
• Water Quality Acts of 1985 and 1987 – sets
goals for swimmable quality and storm
water discharge
Other important water regulations
• Ports and Waterways Safety Act – 1972regulates oil transport and oil handling
facility operation
• Safe Drinking Water Act – 1974 – requires
minimum drinking standards for every
community
– Bacteria, nitrates, arsenic, cadmium,
chromium, lead, mercury, silver, radioactivity,
barium
• London Dumping Convention – 1990 –
calls for end of ocean dumping of waste
and trash
Storm water discharge
• Water Quality Act of 1987 – require
industries and municipalities to have
permits for discharges of stormwater runoff
to control nonpoint source pollution
– Storm water can carry sediment, chemicals,
hazardous wastes, debris
(Ben Raines/Press-Register)
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State of water today
• Large-scale success
• Some water still not drinkable, swimmable,
nor should fish be consumed from it
• Last EPA report (2002): 40% streams, 45%
lakes, 50% estuaries too polluted
– From bacteria, nutrients, metals, sewage
– Cause: urban runoff, sewage, agricultural runoff
Categories of water pollution
Category
Examples
Sources
A. Causes Health Problems
Infectious agents
Bacteria, viruses,
Human and animals
parasites
Organic chemicals
Pesticides, plastics, Industrial, household,
detergents, oil, &
and farm use
gasoline
Inorganic chemicals
Acids, caustics,
Industrial, household
salts, metals
cleaners, surface runoff
Radioactive materials Uranium, thorium,
Mining and processing
production, natural
cesium, iodine,
of ores, power plants,
sources
radon
weapons
Water Pollution
Category
Examples
Sources
B. Causes Ecosystem Disruption
Sediment
Soil, silt
Land erosion
Plant nutrients
Nitrates, phosphates, Agricultural and urban
ammonium
fertilizers, sewage,
manure
OxygenAnimal waste and
Sewage, agricultural
demanding wastes plant residues
runoff, paper mills, food
processing
Thermal
Heat
Power plants, industrial
cooling
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Infectious agents
• Pathogens (disease-causing organisms)
• Waterborne diseases: typhoid, cholera,
bacterial dysentery, polio, infectious
hepatitis, E. Coli, and schistosomiasis
• Main culprit: untreated or improperly treated
human waste
– Contamination of water supply
– Animal feedlot waste runoff into drinking water
supply or food processing factories
Classic case: Cholera
• Cholera: intestinal disease, that if
severe enough, leads to death
(possibly within hours of
exposure)
– Treatable today
• 1854 London: sewage dumped
into River Thames
– Cholera believed to be from “bad
air”
– John Snow proved it was from
water
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Organic chemicals
• Chemicals released in the environment
(includes those intentionally and
unintentionally produced)
• Natural and synthetic organic chemicals
– Pesticides, plastics, pharmaceuticals
Organic chemicals
• Carried by wind and water
• Persistent organic pollutants (POPs): stick
around and travel in food chain
– “Dirty Dozen”: aldrin, chlordane, DDT, dieldrin,
endrin, heptachlor, hexachlorobenzene, mirex,
toxaphene, PCBs, dioxins and furans
• 1,000 wells shutdown in Florida with toxic
levels of pesticides
Plant nutrients & oxygen-demanding
wastes
• Organic waste (sewage, food waste) produce
oxygen-demanding bacteria
• Fertilizer, plant operations, automobile waste
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Inorganic pollutants
• Include natural breakdown and release of
minerals into the water
• Inorganic pollutants: metals, minerals, acids,
salts, nitrates
– Some are not toxic in small amounts
• Metals and industrial solvents:
– Hexavalent chromium (a carcinogen) found in
ground water in Hinkley, CA.
• Groundwater exceeded the Maximum Contaminant
Level of 0.10 ppm with 0.58 ppm
Metals
• Mercury, lead, cadmium, tin, and nickel –
highly toxic in very small doses
– Most widespread is mercury – released from
coal-burning power plants and deposited in lakes
– Predator fish eat small fish – lead to higher doses
of mercury
– Affects: brain, heart, kidneys, lungs, and immune
system
Arsenic
• Odorless and tasteless semi-metal
• Occurs naturally and from agricultural and industrial
practices.
• Possible effects: digestive, skin, partial paralysis,
and cancer.
• New drinking water standard: 0.010 parts per million
(10 parts per billion)
– EPA set water system deadline for January 23, 2006.
– Usually found in ground wells vs. surface water
• Problem in developing countries
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USGS report (2002)
• Sampled 130 streams, testing for 95
contaminants
– Drinking water standards only exist for 14 of the 95
contaminants
Detection frequency (% of samples)
Detection frequency
100
90
80
70
60
50
40
30
20
10
0
Steroids
Nonprescription
drugs
Thermal
pollution
Insect repellent
Dis infectants
Antibiotics
Insecticides
Horm ones
Other pres cription
drugs
• Raising or lowering of
water temperatures
affects aquatic life
• Typically raised by
discharging heated water
from industrial facilities
– Electric power plants,
petroleum refineries, paper
mills, food-processing
factories all release
“cooling water”
– Thermal plume: heated
water discharged into river
and lake
Thermal pollution
• Regulated by EPA
• Can construct artificial cooling ponds or
cooling towers
• Some thermal pollution beneficial:
– Attract wildlife – Manatees of Florida
– Can be hazardous – if plant shuts down, even
temporarily, fatal to wildlife
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