Water

1
Water Soil Pollution

• Chapter 21

2
Water Pollution

• Any physical or chemical change in water that
  adversely affects the health of humans and other
  organisms.
• There are 8 categories
• Sewage
• Disease-causing Agents
• Sediment pollution
• Organic compounds
• Inorganic compounds
• Radioactive substances
• Thermal pollution

3
Sewage

• Sewage is the release of wastewater from drains
  or sewers into waterways.
• Enrichment the fertilization of a body of water
  that is caused by the presence of high levels of
  plant and algal nutrients (nitrogen
  phosphorus).
• Biological Oxygen Demand (BOD)
• The amount of oxygen needed by microorganism to
  decompose the wastes into CO2, H20 minerals
• Measured in mg of dissolved oxygen/liters of
  water

4
Disease-Causing Agents

• Infectious organisms that cause diseases
  including bacteria, virus, protozoa, parasitic
  worms
• Fecal coliform tests test for presences of
  E-Coli
• Safe drinking water should contain no more than 1
  coliform bacteria per 100 ml. of water
• Safe swimming water lt 200 per 100 ml of water
• General Recreational lt 2000 per 100 ml of water

5
Drinking water standards

• California Title 22 Safe Drinking water levels
• MCLs (primary and secondary)
• State and Federal

6
Sediment Pollution

• Excessive amounts of suspended soil particles
  that eventually settle out and accumulate at the
  bottom of a body of water.
• Affects light infiltration and turbidity
• Often carries metals

7
Inorganic Plant Algal Nutrients

• Nitrogen phosphorus that stimulate growth of
  plants and algae
• In estuaries bays can cause red tides marine
  algal blooms
• Dead zones oxygen free environments created by
  algal blooms resulting from introduction of
  nutrients
• Hypoxia oxygen free condition

8
Organic compounds

• Chemicals that contain carbon
• Examples
• Benzene blood disorders
• Dioxins possibly causes cancer, reproductive,
  immune and nervous system damage
• Trichloroethylene (TCE) probably causes cancer

9
Inorganic Compounds

• Lead from paint, leaded gas, pesticides and
  fertilizers
• Create problems at concentrations gt10
  micrograms/deciliter
• Biggest problems to middle age men, pregnant
  women children causing hypertension, high blood
  pressure, miscarriages, problems with mental
  development (respectively)
• Example Mercury
• From coal burning power plants and medical waste
• Accumulates in muscles of fish marine mammals
• Linked to birth defects such as mental
  retardation, cerebral palsy and slow development
  neurological problems
• Heavy Metals - chromium

10
Radioactive Substances

• Unstable isotopes that spontaneously emit
  radiation
• From nuclear power plants nuclear weapons and
  research
• Can be significant as a naturally occurring
  problem
• Radon which increases the risk of lung cancer
  when inhaled over long period of time

11
Thermal Pollution

• Heated water produced and released into waterways
• Results in changes to chemical reactions and
  reduces the dissolved oxygen

12
Eutrophication

• Oligotrophic
• Young lake
• Clear water
• Small aquatic population
• Natural Eutrophication
• Older lake
• Increased photosynthesis
• Cloudy
• Lower DO/hi BOD
• Leads to sedimentation and death of the lake

13
Artificial/cultural Eutrophication

• Result of the enrichment of a lake from inorganic
  nutrients introduced via runoff
• Phosphorus is often the limiting factor in
  freshwater lakes

14
What are Sources of Water Pollution?

• Natural and human activities
• Point source pollution from discharges to water
  bodies at a specific site
• Non-point source pollution pollution to a water
  body over a wide area from runoff (polluted
  runoff)
• NPDES (National Pollutant Discharge Elimination
  System) regulates point-source pollution
• Stormwater NPDES intended to regulate non-point
  source pollution

15
Water Pollution from Agriculture

• Leading source of water quality impairment
• Fertilizer pesticides runoff leading causes
  followed by animal wastes
• gt95 of river and streams and 50 of groundwater
  contain at least one pesticide

16
Water Pollution from Municipalities

• Typically non-point source pollution from runoff
• Includes runoff from roads, untreated
  garbage/waste dumps, construction sediments
  traffic emission
• Combined sewers sewers that direct both
  stormwater runoff and sewage (San Francisco)
• At high rains combined sewer overflow forcing
  untreated wastes to rivers and streams.

17
Water Pollution from Industry

• Top producers include
• Food processing (organics, high BOD)
• Pulp paper (chlorine)
• Electronics (heavy metals)

18
Groundwater

• 50 of U.S. population gets water from
  groundwater
• Most common pollutants in groundwater are
  pesticides, fertilizers, and organics (e.g.
  solvents)
• Sources of groundwater pollutants
• Lea

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Groundwater (cont)

• Sources of groundwater pollutants
• Leaking underground storage tanks (LUST)
• Septic systems
• Leaking well casing
• Dry well/deep well injections
• Landfills with leaky liners (if any)
• Surface impoundments
• Natural occurring substances (e.g. arsenic)

20
How can we treat the sewage water?

• Sewage
• Screening
• Primary sedimentation (settling)
• Aeration with activated sludge
• Secondary sedimentation (settling)
• Other treatments (as needed)
• Chlorination/disinfection (alternative ozone
  and uv radiation)

21
What is the biggest problem with wastewater
treatment?

• Dealing with all the sludge and water that is
  left over at the end.
• Solutions
• Anaerobic digestion makes methane and turns
  sludge to humus
• Application to soil as a fertilizer
• Incineration
• Ocean dumping
• Sanitary Landfill

22
Septic Tanks

• Used for individual houses
• Uses soil to purify wastes
• Must be managed correctly

23
Why is chlorinating water a problem?

• Needed to disinfect the water
• Problem cancer, increased risk of miscarriages
  rare birth defects

24
Why is fluoridation a problem?

• Needed to prevent tooth decay
• Problem unknown health effects such as cancer,
  kidney disease birth defects

25
Laws Controlling Water Pollution

• Safe Drinking Act
• Sets federal standards (MCL) for drinking water
• EPA Website
• Clean Water Act
• Has 2 goals
• Eliminate discharge of pollutants in U.S.
  waterways
• To attain water quality levels that make these
  waterways safe

26
Clean Water Act (cont)

• Requires EPA to set up and monitor national
  emission limitations
• Maximum permissible amount of water pollutants
  that can be discharged from a point source
• Set up Nationally Pollutant Discharge Elimination
  System (NPDES) to limit discharges via permit and
  set up monitoring and penalty system

27
Resource Conservation Recovery Act (RCRA)

• Deals with the storage and disposal of hazardous
  waste
• Requires cleanup of groundwater contamination
• Penalty system for discharges

28
California Laws

• Tend to be more strict than Federal Law
• Title 22 states version of the Safe Drinking
  Water Act
• Porter-Cologne Waterquality Act states version
  of the Clean Water Act
• Proposition 65

29
Soil Pollution

• Any physical or chemical change of soil that
  adversely affects the health of plants or other
  organisms living in or on it.
• Problems include
• Releases of soil from industry agriculture
• Soil acts like a reservoir to hold the waste
• Salinization of soil by depositing additional
  salts from irrigation water and by capillary
  action of over watering that brings salts up.

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Soil Remediation

• Dilution
• Vapor extraction
• Bioremediation
• phytoremediation