Pollution Of Water And Thermal

Pollution

• Water pollution.

• Thermal pollution.

Pollutants, sources and Pollutants, sources and effects of pollution for watereffects of pollution for water

Sources of water pollution

Some of the principal sources of water pollution are:

• geology of aquifers from which groundwater is abstracted • industrial discharge of chemical wastes and byproducts • discharge of poorly-treated or untreated sewage • surface runoff containing pesticides or fertilizers • slash and burn farming practice, which is often an element within

shifting cultivation agricultural systems • surface runoff containing spilled petroleum products • surface runoff from construction sites, farms, or paved and other impervious

surfaces e.g. silt • discharge of contaminated and/or heated water used for industrial processes • acid rain caused by industrial discharge of sulfur dioxide (by burning high-sulfur

fossil fuels) • excess nutrients added (eutrophication) by runoff containing detergents or

fertilizers • underground storage tank leakage, leading to soil contamination, thence aquifer

contamination

Accumulation of litter and organic debris in Salford Quays, a section of the Manchester Ship Canal in Greater Manchester, UK.

Raw sewage and industrial waste flows into the U.S. from Mexico as the New River passes from Mexicali, Baja California to Calexico, California

Pesticides that get applied to farm fields and roadsides—and homeowners' lawns—run off into local streams and rivers or drain down into groundwater, contaminating the fresh water that fish swim in and the water we humans drink. It's tempting to think this is mostly a farming problem, but on a square-foot basis, homeowners apply even more chemicals to their lawns than farmers do to their fields! Still, farming is a big contributor to this problem. In the midwestern United States, a region that is highly dependent on groundwater, water utilities spend $400 million each year to treat water for just one chemical—the pesticide Atrazine.

WATER POLLUTION CAUSES

• PESTICIDES

• FERTILIZERS / NUTRIENT POLLUTION

• Many causes of pollution, including sewage, manure, and chemical fertilizers, contain "nutrients" such as nitrates and phosphates. Deposition of atmospheric nitrogen (from nitrogen oxides) also causes nutrient-type water pollution.

• In excess levels, nutrients over-stimulate the growth of aquatic plants and algae. Excessive growth of these types of organisms clogs our waterways and blocks light to deeper waters while the organisms are alive; when the organisms die, they use up dissolved oxygen as they decompose, causing oxygen-poor waters that support only diminished amounts of marine life. Such areas are commonly called dead zones.

• Nutrient pollution is a particular problem in estuaries and deltas, where the runoff that was aggregated by watersheds is finally dumped at the mouths of major rivers.

• OIL, GASOLINE AND ADDITIVES

• Oil spills like the Exxon Valdez spill off the coast of Alaska or the more recent Prestige spill off the coast of Spain get lots of news coverage, and indeed they do cause major water pollution and problems for local wildlife, fishermen, and coastal businesses. But the problem of oil polluting water goes far beyond catastrophic oil spills. Land-based petroleum pollution is carried into waterways by rainwater runoff. This includes drips of oil, fuel, and fluid from cars and trucks; dribbles of gasoline spilled onto the ground at the filling station; and drips from industrial machinery. These sources and more combine to provide a continual feed of petroleum pollution to all of the world's waters, imparting an amount of oil to the oceans every year that is more than 5 times greater than the Valdez spill.

• Shipping is one of these non-spill sources of oil pollution in water: Discharge of oily wastes and oil-contaminated ballast water and wash water are all significant sources of marine pollution, and drips from ship and boat motors add their share. Drilling and extraction operations for oil and gas can also contaminate coastal waters and groundwater.

• MININGMining causes water pollution in a number of ways:

• The mining process exposes heavy metals and sulfur compounds that were previously locked away in the earth. Rainwater leaches these compounds out of the exposed earth, resulting in "acid mine drainage" and heavy metal pollution that can continue long after the mining operations have ceased.

• Similarly, the action of rainwater on piles of mining waste (tailings) transfers pollution to freshwater supplies.

• In the case of gold mining, cyanide is intentionally poured on piles of mined rock (a leach heap) to chemically extract the gold from the ore. Some of the cyanide ultimately finds its way into nearby water.

• Huge pools of mining waste "slurry" are often stored behind containment dams. If a dam leaks or bursts, water pollution is guaranteed.

• SEDIMENT

• When forests are "clear cut," the root systems that previously held soil in place die and sediment is free to run off into nearby streams, rivers, and lakes. Thus, not only does clearcutting have serious effects on plant and animal biodiversity in the forest, the increased amount of sediment running off the land into nearby bodies of water seriously affects fish and other aquatic life. Poor farming practices that leave soil exposed to the elements also contribute to sediment pollution in water.

• SEWAGE• In developing countries, an estimated 90% of wastewater is discharged

directly into rivers and streams without treatment. Even in modern countries, untreated sewage, poorly treated sewage, or overflow from under-capacity sewage treatment facilities can send disease-bearing water into rivers and oceans. In the US, 850 billion gallons of raw sewage are sent into US rivers, lakes, and bays every year by leaking sewer systems and inadequate combined sewer/storm systems that overflow during heavy rains. Leaking septic tanks and other sources of sewage can cause groundwater and stream contamination.

• Beaches also suffer the effects of water pollution from sewage. The chart below shows the typical reasons that about 25% of the beaches in the US are put under water pollution advisories or are closed each year. It's clear that sewage is part of the problem, even in what is supposedly the most advanced country in the world.

Heavy Metals ( Copper, Mercury, Zinc, Chromium ).

Oil, Grease, And Suspended Solids.

Water Waste Which Contains Numerous Contaminants, Including Hydrogen Sulphide.

• Sources– Effluent from industries

• Electronics and electroplating plants.• Food and beverage processing industry.• Rubber products processing industry.

• Effects– Highly toxic and accumulate in organisms via

food chains.– Mercury can cause nervous disorder in

humans.

Nitrates And Phosphates In Fertilisers

• Sources– Agricultural runoffs

and waste from oil palm and rubber processing mills.

– Untreated sewage ( human faeces and domestic waste ).

Contaminants Contaminants may include organic and inorganic substances.Some organic water pollutants are:

• insecticides and herbicides, a huge range of organohalide and other chemicals

• bacteria, often is from sewage or livestock operations; • food processing waste, including pathogens • tree and brush debris from logging operations • VOCs (Volatile Organic Compounds, industrial solvents) from improper

storage • Some inorganic water pollutants include:• heavy metals including acid mine drainage • acidity caused by industrial discharges (especially sulfur dioxide from

power plants) • chemical waste as industrial by products • fertilizers, in runoff from agriculture including nitrates and phosphates • silt in surface runoff from construction sites, logging, slash and burn

practices or land clearing sites

• Effects– Lead to eutrophication.

• An artificial enrichment of an aquatic system with organic materials or inorganic nutrients.

• Causing an excessive growth of aquatic plant life.

– Leads to algal bloom.• Penetration of lights into water.

( Reduce photosynthesis of aquatic plants )• Toxins production by algae and aerobic bacteria.• Decomposing microorganisms from the death of

photosynthetic organism.

( aerobic bacteria us up O2 in the deeper water at fast rate and kills larger aerobic aquatic organisms)

Herbicide And Pesticides Residues

• Sources– Agricultural runoffs

and waste from oil palm and rubber processing mills.

• Effects– Toxic effects on organism in the water and

human.– Pesticides levels accumulates ( passes through

food chain ).– Accumulation of pesticides in the tissue of final

consumer may kill them or effects their metabolism.

– Lead to lower sperm counts, decrease ovulation, the inability to conceive and birth defects.

Suspended Solids

• Sources– Untreated sewage

• Effects– Reduce light

penetrations.– If biodegradable, they

can decomposed by microbes but requires high demand of O2.

Detergents

• Sources– Untreated sewage.– Domestic wastes.

• Effects– Hard detergents

create foams which reduce the supply of O2 to living organisms living in water.

– Soft detergents

may contain high levels of phosphates which can leads to eutrophication.

Microorganisms ( Bacteria & Protozoa )

• Sources– Untreated sewage.– Animal waste from

farms.– Domestic waste.

• Effects– May cause water-

borne diseases such as cholera if the water is used for drinking.

Lead

• Sources– Underground pipes.

• Effects– Highly toxic.– Can accumulate in the

tissue of living organisms.

– Can impair the mental ability of children.

Thermal Pollution( Raises of the temperature in a body of water )

• Causes– Effluents of industrial

process (discharged of hot water to lakes and rivers ).

– Cooling towers of electrical power stations ( water as cooling agent ).

• Effects– Affects the level of

dissolved O2 in water.– Instant death to some

species which may effect the food chain.

– Encourages the rapid growth of algae.

– May result in permanent changes in the species composition of aquatic ecosystem.

NEARLY FINISHED

THE END