Transcript Chapter 21 Power Point

Chapter 21
Water Pollution and
Treatment
Botkin and Keller
Environmental Science 5e
Look at charts in Text…
Botkin and Keller
Environmental Science 5e
Biochemical Oxygen Demand
• The amount of oxygen required for
biochemical decomposition process
• 3 zones
– A pollution zone
– An active decomposition zone
– A recovery zone
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Environmental Science 5e
Botkin and Keller
Environmental Science 5e
Waterborne Disease
• Outbreaks of waterborne diseases
– Milwaukee, WI
• Cryptosporidium Flu-like symptoms
– Fecal Coliform Bacteria
• Includes E. Coli (200/100ml for swimming)
– Walkerton, ON
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E. Coli outbreak (manure in water system)
Not advised to boil
Very young and old suseptable
Gastrointestinal illness
Vigilant about testing
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Environmental Science 5e
Nutrients
• Eutrophication
– The process by which a body of water develops
a high concentration of nutrients
• Oligotrophic
– Low concentration of nutrients
• Cultural Eutrophication
– When eutrophication is accelerated by human
processes that add nutrients to a body of water
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Environmental Science 5e
Botkin and Keller
Environmental Science 5e
Exxon-Valdez
• 1989 – oil spill recovery inadequate
• 11 million gallons oil spilled
– 14% collected
• Seals, otters, seabirds died
• Jessica – spill near Galapagos Ils.
– Concern for environment, winds carried most
away
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Environmental Science 5e
Botkin and Keller
Environmental Science 5e
Acid Mine Drainage
• Water with a high concentration of sulfuric
acid that drains from mines
• Serious water pollution problem
• Damages aquatic ecosystems, pollutes
bodies of water and degrades water quality
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Environmental Science 5e
Surface Water Pollution
• Water Pollutants are emitted from
– Point Sources
• Distinct and confined sources such as pipes from
industrial or sites
– Nonpoint Sources
• Diffused and intermittent
• Ex) runoffs from streets
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Groundwater Pollution
• Bioremediation:
– a method of treating groundwater pollution
problems that utilizes microorganisms in the
ground to consume or break down pollutants
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Environmental Science 5e
Botkin and Keller
Environmental Science 5e
Botkin and Keller
Environmental Science 5e
Botkin and Keller
Environmental Science 5e
Wastewater Treatment
• Septic Tank Disposal Systems
• Waste Treatment Plants
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Primary Treatment (large organic matter)
Secondary Treatment (aerobic bacteria)
Advanced Treatment (discharged to surface)
Chlorine Treatment (disinfectant)
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Environmental Science 5e
Botkin and Keller
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Wastewater Renovation and
Conservation Cycle
• Steps:
– 1. Return of treated wastewater to crops
– 2. Renovation or natural purification by slow
percolation of the wastewater into soil to
eventually recharge the groundwater resource
with clean water
– 3. Reuse of the treated water
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Environmental Science 5e
Botkin and Keller
Environmental Science 5e
Botkin and Keller
Environmental Science 5e
Botkin and Keller
Environmental Science 5e
Water Reuse
Inadvertent:
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water is withdrawn, treated and returned to the
environment
Indirect:
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Ex) the wastewater renovation and conservation cycle
Direct:
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The use of treated wastewater that is piped directly
from a treatment plant to the next user
Botkin and Keller
Environmental Science 5e
Water Pollution and
Environmental Law
• Environmental Law
– The branch of law dealing with conservation
and use of natural resources and control of
pollution
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Environmental Science 5e