Unit 8: Aquatic and Terrestrial Pollution

Point Source

A single, identifiable source of a pollutant

• Smokestack or wastewater from a water treatment plant

Thermal Pollution:

Heat released into the water produces negative effects to the organisms in the ecosystem

• Variations in temp affect concentration of dissolved oxygen - warm water does not contain as much oxygen as cold water

Nonpoint Sources:

Diffused and can therefore be difficult to identify (multiple sources)

• Pesticides spraying or urban runoff
• Runoff from farms, cities, and neighborhoods
• Fertilizer from suburban lawns
• Greater impact than point sources
• Solution- Limit development on watershed land surrounding reservoirs

US Clean Water Act

• Addressed point sources
• Targeted industrial discharge
• Federal Water Pollution Control Act (1972)
• Renamed Clean Water Act in 1977
• Illegal to discharge pollution without a permit
• Standards for industrial wastewater
• Funded sewage treatment plants
• Mandates restoration and maintenance of water quality

Wetlands:

Areas where water covers the soil, either part or all of them

• Marshes, swamps, estuaries, mangroves, bogs, etc.
• The water in wetlands in either freshwater, brackish, or salt water
• Wetlands provides a variety of ecological services, including water water purification, flood protection, water infiltration, and habitat

Threats to wetlands and mangroves include:

• Commercial development
• Dam Construction
• Overfishing
• Pollutants from agricultural and industrial waste

Bioaccumulation

The selective absorption and concentration of elements or compounds by cells in a living organism, most commonly fat-soluble compounds

• Toxicants build up in animal tissues

Biomagnification

The increase in concentration of substances per unit of body tissue that occurs in successively higher trophic levels of a food chain or food web

• Toxicants concentrate in top predators
• Avoid eating swordfish, shark, and albacore tuna
• Peregrine falcons and brown pelicans are near extinction

Effects of Biomagnification or Accumulation:

• Some effects that can occur in an ecosystem when a persistent substance is biomagnified in a food chain include eggshell thinning and developmental deformities in top carnivores
• Humans also experience harmful effects from biomagnification, including tissues with reproductive, nervous and circulatory systems
• DDT, mercury, and PCBs are substance that bioaccumulate and have significant environmental impacts

Eutrophication

Occurs when a body of water is enriched in nutrients

• The Increase in nutrients causes an algal bloom

Algal Bloom

Rapid growth of algae or cyanobacteria

Effects of Eutrophication:

• When the algal bloom dies, microbes digest the algae, along with the oxygen in the water
• This leads to a decrease in the dissolved oxygen levels in the water
• The lack of dissolved oxygen can result in large die-offs of fish and other aquatic organisms as a result of asphyxiation from lack of oxygen

Hypoxic Waterways

Bodies of water that are low in dissolved oxygen

Nutrient Water Pollution

• Compared to eutrophic waterways, oligotrophic waterways have very low amounts of nutrients, stable algae populations, and high dissolved oxygen
• Sources: Fertilizers, farms, sewage, lawns, golf courses, urban runoff
• Solutions: Reduce nutrient sources, phosphate-free detergents, planting vegetation to increase nutrient uptake, treat wastewater, reduce fertilizer use, etc.

The U.S. Oil Pollution Act of 1990

• Creates a $1 billion prevention and cleanup
• Requires all ships have double hulls by 2015
• Recently, oil spills have decreased
• The oil industry resists such safeguards
• Oil spill up clean up is expensive and involves skimmer boats large floating booms, and GM bacteria

Deepwater Horizon Oil Spill

• Wellhead blowout caused three months of uncontrolled oil to pollute the Gulf of Mexico in 2010
• Largest marine oil spill in history
• 500 million barrels of oil
• The spill caused an 80 square mile kill zone around the well, 4300 sq. miles of fishing closure, 500 miles of contamination, and cetacean death rate twice that of normal
• Millions of gallons of toxic dispersants were used to diffuse the spill and 10 million gallons of oil were burned off the surface
• About 75% of the soil is still in the environment

Plastic pollution has Increased

• Great Pacific Garbage Patch
• Area of tons of suspended plastic particulates in the upper water column in the middle of the north Pacific gyre
• Source: Estimated that 80% comes from N. America and Asia and 20% comes from ships
• Effects: Plastics photodegrade in the presence of sunlight and release endocrine disruptors
  Plastics can also entangle marine life or be eaten
• Solutions: Collection of plastic is energy intensive. Prevention is an easier solution.
• Ban plastic bags, plastic tax, recycle, fines for plastic dumping

Endocrine Disruptors:

chemicals that interfere with the normal functioning of hormones in an animal's body

• The endocrine system is a network of glands in your body that makes hormones and help cell talk to each other
• It blocks the receptor protein binding site of a hormone so that the cell cannot receive a signal

Ground Water Pollution

Groundwater is increasingly contaminated, but is hidden from view

• Difficult to monitor
• Out of sight, out of mind
• Retain contaminants for decades and longer
• Takes longer for contaminants to breakdown in groundwater because of lower DO levels
• Some toxic chemicals occur naturally
• Aluminum, fluorides, sulfates

Ground Water Pollution from Humans

• Water leach through soils
• Pathogens enter through improperly designed wells
• Hazardous wastes are pumped into the ground
• Underground storage septic tanks and gasoline tanks may leak
• Nitrates and pesticides from agriculture
• Manufacturing industries and military sites have been heavy polluters

Chemical Indicator of Water Quality ( pH)

• pH: Potential of hydrogen (log scale)
• Measuring concentrations of H+ ions
• Rainfall is naturally acidic (^) because of absorption of CO2
• pH number indicates the concentration of H+ ions as an exponent of 10
• Acidic water dissolves heavy metals

Chemical Indicator of Water Quality ( Nutrient Concentration)

• Nutrient concentration: Measures phosphates and nitrogen as an indicator of eutrophic conditions
• High levels can lead to dead zones

Chemical Indicator of Water Quality (Hardness)

• Hardness: Measure of amount of CA+2 and MG+2
• Inverse relationship with absorption of metals by fish

Chemical Indicator of Water Quality (Dissolved Oxygen)

• Dissolved Oxygen: The amount of oxygen available in the water for respiration
• Inverse relationship with temperature and organic
• Decreased by runoff, sewage discharge, and removal of vegetation

Biological Indicator of Water Quality (Fecal Coliform Bacteria )

Fecal coliform Bacteria: Indicator of animal waste in water

• Gives people stomach sickness

Biological Indicator of Water Quality ( Biological Oxygen Demand )

Biological oxygen demand: measurement of how much oxygen living things use

Biological Indicator of Water Quality ( Parasites )

Parasites: Measurement of concentration of bacteria (E. coli), virus (Hepatitis), protozoa (dysentery, Giardia), and parasitic worms

Physical Indicator of Water Quality ( Turbidity )

Turbidity: Cloudiness of water, amount of suspended solids in water

• High turbidity caused by erosion, runoff, and high flows
• High turbidity decreases light availability and can be an indicator of microbial growth

Physical Indicator of Water Quality ( Temperature )

Temperature: Amount of thermal energy

• Organisms have their own specific range

The _ sets standards for drinking water containment under the Safe Drinking Water Act for local governments and private water suppliers

EPA

Sedimentation:

Large tank with slow moving water which settles out particles

Flocculation

Process of clarifying water by adding chemicals that precipitate out impurities

Filtration:

Water flows through sand and charcoal

Disinfection:

Chlorine, ozone, or UV light

Septic Systems:

Septic Systems: The most popular method of wastewater disposal in rural areas

• Underground septic tanks separate solids and oils from wastewater
• The water drains into a drain field, where microbes decompose the water
• Solid waste needs to be periodically pumped and landfilled

Effects on Wetlands from Sewage Treatment:

sewage goes into settling tanks and sludge is removed, then activated sludge tank, then wetland.

Primary Sewage Treatment

The physical removal of contaminants in settling tanks (clarifiers).

Secondary Sewage Treatment:

Water is stirred and aerated (activated sludge tanks) so aerobic bacteria degrade organic pollutants.

Sewage that is treated, the leftover solids still contain

phosphates, nitrates, heavy metals, bacteria, and viruses

water treated with chlorines is

piped into rivers or the ocean

Some reclaimed sewage treated water is _

used for irrigation, lawns, or industry

Sewage Treated water is not filtered for

nutrients, pharmaceuticals, and pesticides

Tertiary Water Treatment

The use of ecological or chemical processes to remove any pollutants left in the water after primary and secondary treatment

• The final cleaning process that improves wastewater quality before it is recycled and discharge back into the environment
• Removes any remaining inorganic compounds like phosphorus and nitrogen

What treats water prior to Discharge:

the treated water is exposed to one or more disinfectants (chlorine, ozone, UV light) to kill bacteria

Waste:

Any unwanted material or substance that results from human activity or process

Munincipal Solid Waste (MSW)

Non-liquid waste that comes from homes, institutions, and small businesses

1. Paper, 2. Yard Trimmings, 3. Food Scraps, and 4. Plastics

Industrial Solid Waste

Waste from production of consumer goods, mining, agriculture, and petroleum extraction

Hazardous Waste:

Solid or liquid waste that is toxic, chemically reactive, flammable, or corrosive.

Wastewater:

Water used in household, business, or industry, as well as polluted runoff from our streets and storm drains.

Source Reduction:

Minimizing amount of waste generated.

Predisposal Biological Treatment:

Microorganisms break down organic compounds

Predisposal Chemical Treatment:

Neutralize acids

Sanitary Landfills:

Waste buried in the ground or piled in large, engineered mounds

• Most common method of disposal in US
• Must meet national standards set by the EPA under the Resource Conservation and Recovery Act (RCRA) of 1976
• Can't be built on faults or near bodies of water
• From bottom up - clay, sand, plastic, then gravel or sand

How Landfills Work:

• Waste is partially decomposed by anaerobic bacteria and compresses under its own weight to make more space
• Bacteria produces flammable methane which is trapped by pipes to produce energy energy
• Layered with soil to reduce odor, speed decomposition, reduce infestation by pests
• Larger pieces of solid waste have lower surface area and produce less leachate
• Leachate pipes collect garbage juice which is monitored and treated
• When a landfill is closed, it must be capped or maintained

Landfill Pros:

• No open burning
• Little odor
• Low groundwater pollution
• Built quickly
• Low operating cost
• Handles large amounts of waste
• Land can be reclaimed
• Flushing Meadows in Queens, NY was redeveloped for the 1939 World's Fair

Landfill Cons:

• In 1988, the U.S. had nearly 8,000 landfills
• Today, fewer than 1,700
• Thousands of landfills lie abandoned
• Managers closed smaller landfills and made fewer larger landfills
• All landfills will eventually leak leachate
• Slow decomposition
• Air Pollution from CO2, CH4, VOCs
• Discourages recycling and reusing

Incineration:

A controlled process in which mixed garbage is burned at very high temperatures

Incineration in specially constructed facilities can be an improvement over - ____ burning of trash

open air

• But the remaining ash must be disposed of in a hazardous waste landfill
• Hazardous chemicals, including dioxins, are created and released during burning

Scrubbers:

chemically treat the gases produced in combustion to remove hazardous components and neutralize acidic gases

Incineration Pros:

• Reduce trash volume
• Lower demand for landfills
• Low water pollution
• Concentrates hazardous substances into Ash for burial
• Sale of energy reduces cost
• Modern controls reduce air pollution
• Some facilities recover and sell metals

Incineration Cons:

• Expensive to build
• Cost more than landfills
• Difficult to develop because of opposition
• Contributes to air pollution
• Output approach that encourages waste
• Can compete with recycling facilities

Composting:

The process of helping biodegradable wastes to decompose naturally

• Can be used to enrich soil
• Helps resist corrosion

Home Composting

Householders place water into composting piles, underground pits, or specially-constructed containers

• As waste is added, the heat from microbial action builds in the interior and decomposition precedes
• Earthworms, bacteria, soil mites, sow bugs, and other organisms convert water into high-quality compost

Municipal Composting:

systems that manage the full spectrum of organic wastes is collected from local communities

• Divert food and yard waste from the waste stream to central composting facilities
• Reduce landfill waste
• Encourage soil biodiversity
• Reduces the need for chemical fertilizers
• Makes healthier plants and more pleasing Gardens

First Priority in Integrated Waste Management

• Change industrial process to eliminate use of harmful chemicals
• Purchase different products
• Use less of a harmful product
• Reduce packaging and materials in products
• Make products that last longer and are recyclable, reusable, or east to repair

Second Priority in Integrated Waste Management:

Reuse products
Repair Products
Recycle
Compost
Buy reusable recyclable products

Last Priority in Integrated Waste Management:

• Treat waste to reduce toxicity
• Incinerate waste
• Buy waste in landfills
• Release waste into environment for dispersal or dilution

Refuse (Least energy intensive)

Escape affluenza

Reduce

consume less, redesign manufacturing to use less material.

Reuse

clean and use products again for new purposes, buy used.

Recycle (most energy intensive)

manufacturer new products out of old materials.

The Effects of Recycling

• Recycling is often not financially profitable because it is expensive to collect, sort, and process recycled material
• More material recycled, the lower price
• However, Market forces do not take into account the health and environmental effects of not recycling

Incentive to Address Waste ( Pay as you throw approach):

uses Financial incentives to influence consumer Behavior

• The last waste a house generates the less it is charged for trash collection

Incentive to address waste ( Bottom Pill):

Bottom Pill: consumers receive a refund for returning used bottles.

• Challenges include including new kinds of containers and adjusting refunds for inflation
• Cash Redemption value could be applied to other things
• Taxes on trash can make closed-loop more profitable

Risk:

The probability that some harmful outcome will result from an action

• Exposure to environmental health threats doesn't automatically produce an effect

Risk Assessment (Measurement of risks involved in different activities or substances)

• Identify strength or threat
• Chance and frequency an organism will encounter it
• Amount of exposure to the threat
• Benefits are economic and easy to calculate
• Health risks (costs) are heard to measure probability of affected
• We try to minimize risk, but often misperceived it
• Flying vs. Driving

Approach to Determine Safety ( Innocent until Proven Guilty Approach)

Potential hazard should not be considered a hazard until the scientific data demonstrates that it actually causes harm.

Benefit of Innocent Until Proven Guilty Approach:

Does not slow down technological innovation and economic advancement

Disadvantage of Until Proven Guilty Approach:

Putting into wide use of some substances that may later on turn out to be dangerous

Precautionary Principle Approach:

Assumes the substance is harmful until proven harmless

• Identifies troublesome toxicants before they are released
• May impede the pace technology and economic advance

Hazardous Waste ( Ignitable )

Substances that easily catch fire )natural gas, alcohol)

Hazardous Waste ( Ignitable )

Substances that easily catch fire )natural gas, alcohol)

Hazardous Waste ( Corrosive )

Substances that corrode metals in tanks or equipment

Hazardous Waste ( Reactive )

Substances that are chemically unstable and readily react with other compounds

Hazardous Waste ( Toxic )

Substances that harm human health when they are inhaled, ingested, or contact skin.

Hazardous Waste Sources:

Military, chemical companies, and farms produce the most, but waste disposal is highly regulated

Largest producer of unregulated hazardous waste:

Households

Paints, batteries, lightbulbs, etc.

Types of Persistent Organic Pollutants (POPS)

• POPs do not break down easily in the environment because they are synthetic, carbon based molecules
• They are intentionally produced and used in agriculture, disease, pest control, and industry
• They can be unintentionally produced through waste incineration, trash burning, smoking, and vehicle exhaust
• They can be toxic to organisms because they are soluble in fat, which allows them to bioaccumulate in organisms' fatty tissues.
• Can travel over long distances via wind and water before being redeposited

Bhopal India:

Bhopal India - gas leak from Union Cambridge India unlimited pesticide plant killed thousands in 1984
Released at least thirty tons of Highly toxic gas called methyl isocyanate, as well as a number of other poisonous gases.

Types of Waste: Heavy Metals

• Lead, chromium, Mercury, arsenic, cadmium, tin, and copper
• Used widely in industry for wiring, Electronics, metal plating, and dye
• They enter the environment when they are disposed of improperly
• Heavy metals that are fat soluble in break down slowly can bioaccumulation and biomagnification
• They are often present in sewage

Minamata, Japan

methy-mercury released in Industrial Wastewater from chemical Factory from 1932 to 1968 resulted in thousands of mercury poisonings ( paralysis, weakness, insanity)

E-Waste:

waste involving electronic devices

• Computers, printers. VCRs, Fax Machines, cell phones
• Disposed of in landfills, but should be treated as hazardous waste
• Some people and businesses are trying to use and resume electronics to reduce waste

Disposal Method for Hazardous Waste (Landfills)

Must have several impervious liners and leachate removal

systems

• Designs and construction standards are stricter than sanitary landfills
• Must be located far from aquifers

Method for Hazardous Waste (Surface Impoundments):

Store liquid hazardous waste
-Shallow depressions are lined with plastic and clay

• Water containing waste evaporates, the residue is then transported elsewhere
• Drawback: The underlying clay layer can crack and leak waste

Disposal Method for Hazardous Waste ( Deep Well Injection ):

A well is drilled deep beneath the water table and waste is injected into it

• Long-term disposal method
• The well is intended to be isolated from ground water and human contact
• Drawback: The wells become corroded and leak waste into soil and groundwater

Resource Conservation and Recovery Act (RCRA):

States are required to manage hazardous waste.

• Large generators of hazardous waste must obtain [permits to prevent illegal dumping

Basel Convention:

An international treaty, makes hazardous waste dumping illegal, but it still happens

• Industries that produce hazardous waste tend to sell their products in developed countries with money
• Industries that produce hazardous waste tend to operate in developing countries with weaker environmental regulations and cheaper labor