Test 7 – Flashcards

Point sources discharge pollutants at specific locations through drain pipes, ditches, or sewer lines into standing bodies of water. Examples include factories, sewage treatment plants, underground mines, and oil tankers. Nonpoint pollution sources are broad, diffuse areas, rather than points, from which pollutants enter bodies of water. Examples include runoff of chemicals and sediments from cropland, livestock feedlots, clear-cut forests, urban streets, parking lots, lawns, and golf courses.

It is the primary federal law in the United States governing water pollution. Its objective is to restore and maintain the chemical, physical, and biological integrity of the nation's waters by preventing point and nonpoint pollution sources, providing assistance to publicly owned treatment works for the improvement of wastewater treatment, and maintaining the integrity of wetlands.

Agricultural activities are by far the leading cause of water pollution. Sediment eroded from agricultural lands is the larges source, but other major agricultural pollutants include fertilizer and pesticides, bacteria from livestock and food processing, and excess salt from soils of irrigated cropland.

Industrial facilities, which emit a variety of harmful inorganic and organic chemicals, are a second major source of water pollution.

Mining is the third biggest source of water pollution. Surface mining disturbs the land, creating major erosion of sediments and runoff of toxic chemicals.

They are : parking lots - grease, toxic metals, and sediments that collect on impervious surfaces are a major source of nonpoint pollution. Additionally parking lots disrupt the hydrologic cycle by preventing rain from soaking into the ground and worsening local flooding and erosion.

It was so polluted with flammable chemicals that it caught fire several times in the 1950s and 60s as it flowed through the city of Cleveland. A highly publicized photo of this river burning in 1969 led to point-source legislation (evidence and validation for legislators working on the Clean Water Act. )

Nutrient pollution is primarily nitrate (NO3 -1) and phosphate (PO4 -3) pollution from fertilizers, farms, sewage, lawns, and golf courses. Solutions to nutrient pollution include: Phosphate-free detergents (laundry is mandated, dishwashing is here but not mandated yet) Planting vegetation to increase nutrient uptake Treat wastewater Reduce fertilizer application

It is the natural nutrient enrichment of a shallow lake, estuary, or slow-moving stream, mostly from runoff of plant nutrients from surrounding land.

Pathogens and water borne diseases cause more human health problems than any other type of water pollution.

The solutions are to treat sewage, disinfect drinking water public education to encourage personal hygiene and Government enforcement of regulations

They come from natural and synthetic sources Pesticides, petroleum products, synthetic chemicals Arsenic, lead, mercury, acid rain, acid drainage from mines.

They are: Legislating and enforcing more stringent regulations of industry Modify industrial processes Modify our purchasing decisions

They cone from clear-cutting, mining, poor cultivation practices.

They are: : better management of farms and forests; avoid large-scale disturbance of vegetation

It is tha warmer water holds less oxygen and dissolved oxygen decreases as temperature increases Industrial cooling heats water Removing streamside cover also raises water temperature. Water that is too cold causes problems Water at the bottom of reservoirs is colder When water is released, downstream water temperatures drop suddenly and may kill aquatic organisms

Biological indicators: presence of fecal coliform bacteria and other disease-causing organisms Chemical indicators: pH, nutrient concentration, taste, odor, hardness, dissolved oxygen Physical indicators: turbidity, color, temperature

Biological Oxygen Demand (BOD) - The amount of oxygen used for biological decomposition. The more wastes, sewage, algae, ect, the higher the BOD. BOD and dissolved oxygen (DO) are inversely related - the lower the BOD of a body of water, the higher the DO available for aquatic life. As BOD increases, the amount of DO available for aquatic organisms decreases. If DO is below 5 mg/L, the EPA designates a body of water as polluted.

Groundwater is increasingly contaminated, but is hidden from view. It is difficult to monitor. It retains contaminants for decades and longer. It takes longer for contaminants to breakdown in groundwater because of the lower dissolved oxygen levels

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 (sometimes, depends on the system)

Primary treatment = the physical removal of contaminants in settling tanks (clarifiers) A physical process - uses screens and a grit tank to remove large floating objects and allow solids to settle out. Then, the waste stream flows into a primary settling tank where suspended solids settle out as sludge. By itself, primary treatment removes about 60% of suspended solids and 30-40% of oxygen-demanding organic wastes from sewage.

Secondary treatment = water is stirred and aerated so aerobic bacteria degrade organic pollutants. A biological process. Aerobic bacteria remove as much as 90% of dissolved and biodegradable, oxygen-demanding organic wastes. Removes about 70% of most toxic metal compounds, 70% of phosphorus, and 50% of nitrogen. Secondary treatment removes only a tiny fraction of long-lived radioactive materials and persistent organic substances such as pesticides, and does not kill pathogens.

In some areas, tertiary sewage treatment is used. A series of specialized chemical and physical processes are used to remove specific pollutants left in the water after primary and secondary treatments - usually phosphates and nitrates are removed from wastewater. Tertiary treatment costs a lot, and is not widely used.

Natural and artificial wetlands can cleanse wastewater After primary treatment at a conventional facility, water is pumped into the wetland (or sometimes after secondary treatment to absorb nitrates and phosphates) Microbes decompose the remaining pollutants Cleansed water is released into waterways or percolated underground Constructed wetlands serve as havens for wildlife and areas for human recreation More than 500 artificially constructed or restored wetlands exist in the U.S.

Natural sources include dust, pollutants from fires and volcanic eruptions, and VOCs released from some plants. Most natural pollutants are spread out over the globe, or removed by chemical cycles, precipitation, or gravity. However, chemicals emitted from volcanic eruptions and some large forest fires can temporarily reach harmful levels in areas where they occur.

Human sources can be further classified as Mobile (cars, buses, trains) or stationary (non-moving sources).

They are large areas with many pollutants (urban area, industrial park, ect). Human inputs of outdoor air pollutants occur mostly in industrialized and urban areas where people, cars, and factories are concentrated.

Primary air pollutants - harmful chemicals emitted directly into the air from natural process or human activity. Secondary pollutants - primary pollutants react in the atmosphere to form other NEW harmful chemicals.

Carbon monoxide (CO) - colorless, odorless, highly toxic gas. Formed during incomplete combustion. Major sources include motor vehicle exhaust, burning of forests and grasslands, tobacco smoke, open fires and inefficient stoves. Carbon monoxide can trigger heart attacks and asthma attacks at low levels, and is fatal at high levels. Nitrogen oxides (NOx) - Include Nitric oxide (NO) and nitrogen dioxide (NO2). They are both formed in combustion in auto engines and coal burning. NO is also produced naturally by bacteria, and NO2 is emitted from fertilizers and animal wastes. They are lung irritants - triggering problems with lung conditions and impairing the immune system. NOx are both important in photochemical smog, and NO2 plays a large role in acid rain. . Sulfur Dioxide (SO2)- Is a colorless gas with an irritating odor. About one third of the SO2 in the atmosphere is from natural sources, the rest (and up to 90% in urban areas) comes from combustion of sulfur-containing coal in power plants and oil refining. In the atmosphere SO2 is converted to the secondary pollutants sulfuric acid and particles of sulfate. The secondary pollutants aggravate breathing, and damage plant tissue and aquatic life. They can also corrode metals and damage paint, paper, stone, and leather. Particulates - Suspended particulate matter (PM) are a variety of solid and liquid particles that remain suspended for long periods of time. Over 60% of PM in outdoor air comes from natural sources such as dust, wild fires, and sea salt. The remaining comes from human activities such as coal-burning, motor vehicles, dust activities such as plowing, construction, or unpaved roads. Ozone - (O3) - A colorless and very reactive gas, is a major component of photochemical smog. Can cause breathing problems, aggravate heart and lung diseases, weakens the immune system, and damages plants, rubber, fabrics, and paints. . Lead (Pb) - Can be inhaled from airborne particles or ingested (eaten) - causes IQ issues and kidney disease. Lead used to be an additive to gas to help engines run better, but has been taken out in the U.S. and Europe. By 2007, the U.S. had reduced airborne lead emissions by 99.5% - the remaining airborne lead emissions are from metal smelters and battery manufacturing.

Maximum pollution levels of each of the six criteria air pollutants are set by the EPA, and these concentrations are called the National Ambient Air Quality Standards (NAAQS).

Five natural factors help reduce outdoor air pollution. They are: Gravity helps particles heavier than air settle out of the atmosphere and fall to earth Rain and snow help cleanse the air of pollutants Salty sea air and spray from oceans wash out water-soluble pollutants that travel over the ocean Winds dilute pollutants. Some pollutants are removed from the atmosphere by chemical reactions - SO2 reacts with oxygen to form SO3, which reacts with water to form H2SO4, which falls to the earth as acid rain.

Urban buildings slow winds, and reduce dilution and removal of pollutants. Hills and mountains slow the flow of air to valleys and allow pollution to build up in them (LA is a valley - LA has smog problems) High temps increase photochemical smog formation = global warming will increase smog Emissions of VOCs from certain tree and plant species in wooded urban and suburban areas can play a large role in the formation of photochemical smog. (sweet gums, poplar, some oak species, and kudzu) The grasshopper effect - volatile air pollutants carried by winds travel to the arctic, where they are deposited - pilots for decades have reported reddish-brown haze over the poles. Temperature inversions - Cause pollutants to build to high levels over urban areas. A layer of cool air trapped between two layers of warmer air keeps pollutants trapped near ground level.

Industrial smog - formed primarily from burning coal - caused primarily from sulfur dioxide gas and the resulting formation of sulfuric acid. Ammonia in the atmosphere also reacts with the sulfuric acid to produce ammonium sulfate - these particles and soot give the smog a gray color. (so called "grey smog") . Industrial smog used to be a huge problem, but today is rarely a problem in developed nations with tighter pollution controls on coal power plants, and where coal is not burned as a home heat source.

Photochemical smog is a mixture of primary and secondary pollutants formed by the influence of UV light from the sun. Photochemical smog begins with nitrogen present in fossil fuels being burned by the internal combustion engine and producing nitric oxide (NO) and some Volatile Organic Compounds (VOCs).

the deposition of acid, or acid-forming pollutants, from the atmosphere onto Earth's surface - must have a pH of less than 5.6.

Dry acidic deposition - potentially acidic particles settle out quickly (2 - 3 days) on surfaces near pollution source (only actually an acid when mixed with water). Wet acidic deposition - acidic particles in atmosphere mix with precipitation, and fall to earth as acid rain. Can take from 4 to 14 days, and can precipitate up to 600 miles from pollution source.

Sources of Acid Deposition - Originates from burning fossil fuels that release These compounds react with water to form sulfuric and nitric acids The primary natural sources for sulfur dioxide are volcanoes, fires, and wetlands. The primary man-made sources for sulfur dioxide are burning coal, oil, and natural gas, and ore smelting.

Nutrients are leached from topsoil Soil chemistry is changed Metal ions (aluminum, zinc, etc.) are converted into soluble forms that pollute water Widespread tree mortality Affects surface water and kills fish Damages agricultural crops Erodes stone buildings, corrodes cars, erases writing on tombstones

New technologies such as fluidized bed combustion have helped SO2 emissions are lower Clean Air Act Amendments of 1990 have significantly contributed to the lowering of SO2 emissions from coal-fired power plants.

Clean Air Act established air pollution regulations enforced by cities and states, focused on six criteria pollutants and setting national standards (NAAQS).

The Air Quality Index (AQI) is based on 5 of these (not lead). Numeric scale - anything over 100 is unhealthy, especially to sensitive individuals. Anything over 300 is hazardous to all individuals.

TRI - toxic release inventory - requiring over 30,000 utilities, mines, refineries, and chemical companies to report their air pollutant releases and waste management methods for 667 toxic chemicals

In developing countries, the indoor burning of wood, charcoal, dung, crop residues, and coal in open fires or poorly ventilated stoves exposes people to dangerous levels of particulate air pollution.

According to the EPA, the four most dangerous indoor air pollutants are tobacco smoke, formaldehyde, radioactive radon-222 gas, and very small particles.

Other indoor air pollutants that cause problems are asbestos, carbon monoxide, lead, biological particles (bacteria, mold, dust mites), and VOCs.

Specific pollutants are found in different aged buildings - lead and asbestos are generally only found in older buildings, while formaldehyde and VOCs tend to be found at high levels in very new buildings, or buildings with new flooring or cabinets. Houses with wood burning stoves tend to have issues with carbon monoxide and particulates.

A sick building is one in which many people report adverse health effects that they believe are from spending time in the building. These adverse health effects must be persistent and reduce or disappear when building occupants go outside. EPA studies indicate that one in five commercial buildings in the U.S. is "sick," exposing employees to health risks.

Environmental tobacco smoke (ETS) is produced from combustion of tobacco. Health problems include cancer, respiratory problems, emphysema, and ear infections in children exposed to secondary smoke. Methods to prevent and clean up include stopping smoking. Formaldehyde is found in furniture stuffing, particle board, new furniture, plywood, and carpeting. It is a severe irritant of eyes, nose, and lungs, causes lung cancer, nausea and dizziness, and impaired breathing. Improved ventilation will help, as well as alternative building materials. Radon: Radon-222 is a colorless, odorless radioactive gas produced from radioactive decay of uranium-238 in rocks and soils. This isotope is much more concentrated in phosphate, granite, and shale. Radon gas seeps up from the ground through cracks in the foundations of homes and builds up to high levels. Lead and Asbestos - lead is found in paint manufactured before 1978, and asbestos is found in insulation, ceiling tiles, and spray-on fire retardant in buildings built before the 1980s. 1) Asbestos causes lung cancer and respiratory issues, and AIRBORNE lead particulates cause impaired mental and physical development, headaches, seizures, and birth defects.