Topic 7: Water pollution, solid waste and hazardous substances

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Topic 7 Water pollution, solid waste and
hazardous substances

• Control of major point and non-point pollution
  problems

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Water pollution control

• Recreational benefits are much more important
  for water pollution control than for air
  pollution control.
• Water and sewage treatment is more of an option
  than on-site pollution control.
• Pollution and contamination is just as much a
  problem for groundwater as for surface water.
• Water pollution control must increasingly take
  into account both point and non-point sources of
  pollution.
• Increasingly problems of coastal and ocean
  pollution, e.g. from oil spills and ocean dumping.

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Classifying water pollutants stock versus fund
pollutants

• fund pollutants
• Degradable organic residuals that are broken
  down by bacteria, usually monitored by measuring
  dissolved oxygen (DO) of the water or the
  biological oxygen demand (BOD) caused by an
  effluent.
• Thermal injection of heat into water source
• Eutrophic excessive nutrients (nitrogen,
  phosphorous) leading to too much aquatic plant
  growth.
• Persistent pollutants inorganic synthetic
  chemicals that are only partially broken down
• Bacteria, viruses, artificial hormones from
  domestic and animal wastes
• stock pollutants
• Inorganic chemical and minerals that cannot be
  removed by natural processes (lead, cadmium,
  mercury, some agrochemicals).

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Water pollution control in the US

• National effluent standards general standards
  for broad categories of sources based on the
  adoption of specific technologies by industrial
  sector.
• Problem 1 industries choose specific EPA
  recommended technology rather than the best
  technology to reduce discharges
• Problem 2 uniform standards are not
  cost-effective but do reduce administrative costs
  of control.

• Subsidies for municipal waste treatment
• Problem 1 Subsidies are for construction but not
  operation and maintenance
• Problem 2 Construction costs tend to spiral out
  of control

Doubtful that current US approach is very
cost-effective
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Alternative water pollution control policies

• Need for reform most studies suggest that the
  uniform standards and treatment approach is
  around 3 times more expensive than least-cost
  control.
• Relative little use of marketable pollution
  permits for water pollution compared to air
  pollution control.
• Some European countries have demonstrated that
  effluent charges are possible and can be
  cost-effective.
• Current laws do little to control nonpoint water
  pollution, even though it may be possible to
  reduce nitrogen, soil and agrochemical runoff
  from farms and phosphorous from municipal waste.
• Oil spills and ocean dumping are usually
  controlled through the threat of litigation,
  although there are high administrative costs for
  the EPA pursuing court cases and liability
  limitations of polluters.

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Solid waste and recycling

• Whether a by-product of the economic process is
  classified as waste often depends upon economic
  and technical characteristics of production, and
  the potential for recycling.
• Historically, greater reliance has been on new
  or virgin materials rather than recycled
  materials.
• However, as land has become more scarce, disposal
  costs rise and urban populations increase,
  recovery and recycling of solid waste becomes an
  option.
• Economic feasibility of recycling also depends on
  demand for recycled products, recovery and
  recycling costs and the costs of virgin materials
  over time.

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The economics of recycling aluminum cans
Price (/can)
Supply of cans from recycled material (SR)
Supply of cans from virgin material (Sv)
P1
Demand for cans (D)
Quantity of aluminum cans (Q)
Q1
Q2
Recycling ratio Q2/Q1
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Increasing the recycling ratio aluminum cans
(a) a tax on virgin materials
(b) investing in recycling
P
P
SR
SR
SR
SV
SV
SV
D
D
Q
Q2
Q1
Q
Q2
Q3
Q3
Q4
Q1
P
SR
(c) a fall in demand
SV
D
D
Q
Q2
Q3
Q1
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Toxic substances and hazardous wastes

• There are 2 million known chemical compounds, of
  which 55,000 are in commercial use.
• Many exhibit little or no toxicity, and even
  those that are very toxic can pose little risk if
  they are isolated.
• Toxicity occurs when a living organism
  experiences detrimental effects once exposed to a
  substance.
• Two main health effects of concern with toxic
  substances are
• risk of cancer
• effects on reproduction

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Toxicity, latency and uncertainty

• The latency of the exposure-effect relationship
  is determined by the type of toxicity of the
  substance
• acute toxicity short-term exposure produces a
  detrimental effect on the exposed organism.
• chronic toxicity detrimental effect on exposed
  organism arises only after prolonged and/or
  continued exposure.
• mutagen/carcinogenic if chronic toxicity leads
  to abnormal cell growth, the substance is a
  mutagen and is likely to be carcinogenic.
• Uncertainty is a large factor in standards and
  control
• Lab tests are imperfect simulations for
  real-world exposure.
• Synergistic effects mean that other environmental
  variables matter.
• Biological magnification/accumulation, cocktail
  effects may be significant factors in health
  risks.

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Control policies and toxic contamination

• Occupational hazards Although studies suggest
  that wages do contain a risk premium for more
  risky occupations, the ability of a worker to
  accept higher wages depends on information
• Role of government enact laws requiring full
  disclosure of occupational hazards.
• Product risk Consumers can be exposed through
  consuming a product, but consumer choice depends
  on full information on product safety
• Role of government should assure that consumers
  receive adequate information on product risks.
• Third party contamination - Uncompensated
  environmental risk (externality)
• Role of government require better information on
  the risk and use the court system to impose
  liability.

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Efficient control for toxic substances

• In contrast to air and water pollution, standards
  and litigation may be an efficient control policy
  for toxic substances.
• Usual approach is to establish negligence
  (failure to exercise due care) or strict
  liability (if an activity is inherently
  hazardous, liability automatically follows if
  damage occurs).
• Plaintiff must 1) identify the harmful
  substance, 2) demonstrate that the defendant was
  the source, and 3) prove that identifiable
  damages resulted.
• Litigation is weakest in dealing with large-scale
  emissions of hazardous substances by many sources
  that exposes large populations to risks.
• Litigation is costly for plaintiffs and for
  society in general

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Alternative mechanism assurance bonds

• Dated assurance bond required for any disposal
  of hazardous waste, the amount paid depends on
  the control authorities assessment of the costs
  of environmental repair if future damage occurs
  any time between posting date and refund date.
• In case any site requires restoration as a result
  of hazardous waste damage, the funds invested in
  the bond could be used to finance the repair.
• Any unused proceeds of the bond (plus interest)
  would be refunded at a set future date.
• Advantages
• Provides incentive to reduce hazardous/toxic
  discharge, as less environmental damage means a
  greater refund.
• Ensures money is available for any clean-up
• Reduces costly litigation.
• Problems
• Requires knowledge of potential damages to
  establish correct bond amount.
• Funds should be sufficient for victim
  compensation and repair.