Chapter 18: Water Pollution Flashcards
How many years ago was Lake Erie on the brink of collapse?
40 years
When did President Nixon sign the Clean Water Act?
In 1972
Clean Water Act
This Act has been called the nation’s most popular environmental legislation. Goal of the act: all of the nation’s water should be fishable and swimmable
What percent of Americans believe we should invest in clean water?
90%
What are the 3 most common sources of pollution today?
- Erosion from farm fields and construction sites
- Agricultural runoff
- Airborne mercury and sulfur
Pollution
Is actually any physical, biological or chemical change that adversely affects living organisms or makes water/air unsuitable for use
Point Sources
Discharge pollutants from specific locations
Examples: Factories, power plants, sewage
plants, oil wells, underground coal mines, etc.
These facilities have pipes, ditches, etc.
Nonpoint Sources
Have no specific location of discharge
Examples: Runoff (from fields, feedlots, golf
courses, logging areas, construction sites,
parking lots, etc), atmospheric deposition
(contaminants carried in air are precipitated
into watersheds and surface waters).
What 2 groups are water pollution divided into?
Pollutants causing health problems and pollutants causing ecosystem disruption
Pollutants causing health problems
Infectious agents, inorganic chemicals, organic chemicals and radioactive materials
Pollutants causing ecosystem disruption
Sediment, thermal, plant nutrients
Pathogenic organisms cause what?
Diseases
The most important water born pathogens cause what diseases?
Typhoid Cholera Bacterial and amoebic dysentery Enteritis Polio Infectious hepatitis Shistosomiasis
What 3 diseases are caused by aquatic insect larvae?
Malaria, yellow fever, filariasis
What fraction of children under 5 die of water born diseases?
2/3
How is drinking water disinfected?
Chlorination process
Coliform Bacteria
Any bacteria that lives in the colon or intestines of humans or animals.
What are some examples of coliform bacteria?
Eschericha coli (E.coli), Shigella, Salmonella, and Lysteri
When is water not swimmable?
If colony count exceeds 200 per 100 ml of water
How many parts per million of oxygen is required for aquatic life to survive?
6 ppm
How many parts per million of oxygen do fish like?
8 ppm
How many parts per million only support worms and other decomposers?
2 ppm
Organic waste and fertilizers are rich in what two elements?
Nitrogen and phosphorus
What does BOD stand for?
Biochemical Oxygen Demand
BOD tests incubate water for how many days?
5 days
What does DO stand for?
Dissolved Oxygen
Oxygen Sag
Term for oxygen levels decreasing downstream
Water Clarity
Means transparency. It is affected by sediments, chemicals and the concentration of plankton in the water.
How is water visibility determined?
With a secchi disk
Oligotrophic
Rivers or lakes with clear water and low bioproductivity.
Eutrophic
Waters with high nutrient levels and bioproductivity.
What is the rate of eutrophication determined by?
Water chemistry, depth, inflow, mineral content, and biota.
Cultural Eutrophication
Nutrient increase is human-caused (anthropogenic).
Red Tide
Algal bloom of which toxins are contained in the algae. The water is undrinkable, unswimmable, and aquatic life dies. It can be other colors.
Dead Zones
Areas with toxic algae
Pfiesteria piscicida
A dinoflagellate, secretes nerve-damaging toxins. The toxin was identified in 2007 and has been found to be the source of fish mortality and human illness.
Inorganic Pollutant: Metals
Such as lead, mercury, cadmium, tin and nickel are highly toxic in high concentrations. Mercury contamination is the most common. Mine drainage is a source as well as natural leaching from rock material
Inorganic Pollutant: Nonmetalic Salts
Often found naturally in soil. Examples are selenium and arsenic compounds.
Inorganic Pollutant: Acids and Bases
Industrial processes and coal-mining are sources. These sources release high and low pH solutions.
Atrazine
The most commonly used U.S. herbicide, is an endocrine disruptor ( disrupts normal sexual development of organisms).
Sediment degrades what?
Water quality
Thermal Pollution
Pollution is considered to be thermal when it changes the natural heat content of water.
In 1948, what fraction of Americans used a sewage treatment system?
1/3
In 1972, the Clean Water Act required what?
Permitting and treatment of wastewater
In 1998, the regulatory practices changed to what?
Watershed monitoring; Over 4,000 watersheds are monitered
TMDL
Total Maximum Daily Load; Is measured to determine water quality based on testing levels of pollutants.
Navigable waters do not include what?
Wetlands, ponds, tributary streams, and intermittent desert rivers
In the U.S, what percent of people use a secondary wastewater treatment?
70%
In Sweden, what percent of people use a secondary wastewater treatment?
98%
Many poor countries’ surface water comes from what?
Sewage discharge
What fraction of people in the U.S and what percent of people in rural areas rely on aquifers?
1/2; 95%
MTBE
Methyl Tertiary Butyl Ether; A gasoline additive, is the most common groundwater contaminant and is a suspected carcinogen.
Open-Ocean pollution is easy/hard to control.
Hard
What kind of pollution is the most common ocean pollution?
Oil
Source Reduction
The cheapest and best way to reduce pollution.
What is an example of source reduction?
Lead in air was a problem
Source – lead in gasoline
Solution – remove the lead from gasoline
Municipal Sewage Treatment
Consists of an engineering-designed facility that implements treatment of wastewater. Treatment occurs in phases: primary, secondary and tertiary.
Influent
Raw Sewage
Primary Treatment
Removes solids and suspended sediments using screens and filters. Grit tanks allow sediments to settle out. Many microbes are still in the effluent.
Secondary Treatment
Uses aeration of activated sludge, followed by sludge removal and chlorination of effluent. The sludge is rich in aerobic bacteria that helps breakdown organic waste. Chlorination kills remaining microbes (some plants use UV light or ozone). Water should be about 90% clean (but not potable!)
Tertiary Treatment
Done at some facilities. It removes even nitrates and phosphates. Secondary treated effluent can cause eutrophication but tertiary will not.
Effluent
Water discharged from wastewater treatment.
What organisms help break down toilet paper, feces, and food particles?
Anaerobic organism
1972 Clean Water Act
Made clean water a national priority. It was one of the most successful pieces of legislation in history. Goal was to make U.S. waters fishable and swimmable. It required point sources of pollution to have discharge permits. It also required zero discharge rates for 126 toxic pollutants.
Water Quality Act
An amendment to the 1972 act that took place in 1987. Encouraged the separation between storm water and sanitary sewer lines.
U.S. Safe Drinking Water Act
1974, it required the EPA to set safe drinking water standards by setting maximum containment levels for water pollutants that negatively impact human health.
Public Health Security and Bioterrorism Preparedness and Response Act of 2002
This act served to assess community water systems for vulnerability to terrorist attack that would disrupt the ability to provide a clean, safe drinking water supply.
Superfund Program
Created in 1980 for remediation of sites containing toxic waste. Provides federal dollars to remediate contaminated sites.
