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KAAF UNIVERSITY COLLEGE CIV 364 ENVIRONMENTAL QUALITY ENGINEERING Course Outline Introduction to environmental quality engineering Air pollution Soil erosion and sedimentation control Storm Sewer Design Water and Sewage Treatment

Management of solid waste 1) Recycling 2)incinerators 3) Landfills Development of groundwater resource Groundwater pollution and control

Management of Hazardous and Toxic waste 1) acid Mine Drainage 2) Disposing of Nuclear and chemical waste 3) Bio-reclamation 4) insitu-vitrification Course work 30%, Exams 70%

WHAT IS INCLUDED IN ENVIRONMENTAL ENGINEERING FUNDAMENTALS: Mathematics, Physics, Chemistry, Microbiology, Thermodynamics, Economics, Computing, Legal Social Sciences and Geology Applications: Air Pollution Control, Erosion and sedimentation control, Hydrology, Solid waste, water quality, water and wastewater treatment, hazardous waste, groundwater resource management and groundwater pollution control. Environmental Work is Multidisciplinary!!!! What do we Protect & Conserve?1

PROTECTION: Health of Humans, Animals, Plants, microorganisms Water and Water Supplies Surface water (rivers and lakes) Groundwater Coastal

RESOURCE CONSERVATION Raw materials & Natural resources, energy/fossil fuels, land consumption

What causes pollution? Human Activity Municipal Wastewater and Solid Waste Land Development Material Consumption i.e. plastic bottles, newspapers etc.

Unsustainable Development Water & Air Water Quality Drinking water supply and treatment Waste water treatment Contaminated Runoff

Surface water quality Protection of fresh and marine habitats

Air Quality Particulate control Acid rain smog

Microbial analysis2

Understanding the impact of microorganisms Pathogenic (disease-producing) bacteria synthesize toxic substances that cause disease symptoms. E.g., clostridium tetani causes tetanus. Botulism bacteria cause food poisoning. Viruses Most bacteria are harmless and many are beneficial. Bacteria are known to biodegrade toxic chemicals in soils and groundwater. There is the need to identify these microorganisms and make them work for us.

Solid and Hazardous waste Solid waste management Landfill Design Recycling Incineration with energy recovery

Hazardous Waste Where does it come from? Industries such as chemical, pharmaceutical, electronics, metal smelting plants,

Coastal engineering 50% of worlds population lives within 50 miles or 75 kilometres of the coast. Sea water intrusion in fresh groundwater Sea level rise and beach erosion Impact of storms on coastal infrastructure and natural environment

JOB OPPORTUNITIES Consulting Provide engineering services to Government and industry

Academia i.e. teaching and research Government:

EPA, NADMO, ministry of science.3

develop and enforce regulations and also issue permit Design of treatment facilities and landfill sites

1. AIR POLLUTION The quality of the air we breathe has a major impact on public health and safety. Therefore it is important for various Governments of this global village to have regulations (EPA) which define the nations air quality goals (i.e., the levels of acceptable pollution which have a minimal effect of public health. The means to achieve these goals are expressed in the form of permissible emission levels. Adequate air pollution control measures such as dust emission control are necessary to enhance public safety, health, welfare and comfort and to reduce damage to any property, residence or business. A large quantity of atmospheric dust triggers Asthma in children with breathing problems. Economically, business are forced to close down because of dust emissions or newly painted residential or business building turn brown overnight and cars have to be washed daily. Occasionally, temporary dust emissions are a nuisance than a health impact on the ambient atmosphere. DEFINITION: Air pollution may be defined as the presence in the atmospheric air of one or more contaminants or combinations thereof in such quantities and of such durations as may be injurious to human, animal or plant life, or property, or which interferes with the comfortable enjoyment of life or property or conduct of business. 2 TYPES OF AIR POLLUTION A) B) C) D) E) F) Particulate matterDust and /or volcanic ash Smog Acid rain Noise Smell

2 a. Particulate Matter Dust Fugitive Emissions Causes Dust particles are generated when wind speed exceeds 40 km/h. Sandy and silty soils tend to be the most susceptible. Increased traffic speed on new or un-tarred roads or large construction4

projects such as new sports arena also generate dust. Mining activities such as blasting or the illegal mining called Galamasey are prime generators of fugitive emissions. Plant emissions The source of the dust emissions can be traced to a single point source, for example, cement plant, drilling and crushing of rocks at a quarry site. It is easy to control the dust emissions in plant emissions than in fugitive emissions. PRACTICES TO CONTROL DUST STAGING Staging is sometimes called phasing. With staging, grading and stabilization are finished in one area before proceeding to the next. Staging allows the contractor to take advantage of the existing vegetation on the site which acts as a wind barrier. Plan the stages or phases of development so that only areas which are actively under construction are exposed. WIND BREAKS Trees or other tall vegetation along the perimeter or intermittently across the site must be left in place to serve as wind barriers. The proper use of seeding and planting of grasses in open areas must be encouraged. WATERING Another temporary measure for controlling dust is to keep the bare soil moist by watering. New roadways from Tetteh Quarshie to Mallam or Accra /Kumasi road especially at Achimota and Dome areas may have to be watered continuously. CHEMICAL BINDERS In addition to watering, chemical binders or surfactants can be sprayed on the soil surface. The chemical (emulsified asphalt, or bond coat or asphalt cement) penetrates in the soil and bonds the individual soil particles.

CONTROL OF VEHICLE SPEED In a construction site, or on un-tarred roads in urban areas, it is imperative to control vehicular speed to reduce dust emissions. 2b. SMOG

CARBON MONOXIDE5

Carbon Monoxide (CO) is a toxic gas produced in gasoline engines as a result of incomplete combustion of fuel. It is also a component of tobacco smoke. Its toxic effect occurs because it combines with haemoglobin (pigment of red blood cells responsible for the transport of oxygen) more effectively than oxygen. Furthermore, carbon monoxide does not dissociate readily from the haemoglobin. Thus, when a person breathes carbon monoxide, increasing quantities of haemoglobin become unavailable for oxygen transport, and the body cells soon suffer. CARBON DIOXIDE (CO2)) Carbon dioxide is nontoxic gas which is produced in greater quantities from complete combustion of gasoline or diesel fuel engines. A second important source of additional atmospheric carbon dioxide is global deforestation, the cutting of tens of millions of acres of forests each year. A third source of carbon dioxide emission is coal burning or diesel power plants Carbon dioxide is known as a major contributor to the greenhouse effect or global warming because it traps heat. Atmospheric carbon dioxide allows energy in the form of sunlight to enter but absorbs and holds that energy once it is converted to heat. ACID RAIN Acid rain is a pollution problem resulting from the oxidation of pyrite (FeS2) Present in anthracite coal. When coals are burned to generate electricity, sulphur dioxide gases are produced and escape from stack exhausts to the atmospheric air. SULPHUR DIOXIDE Sulphur Dioxide is a heavy, colourless gas with an odour like a struck match. The gas combines easily with water vapour, forming aerosols of sulphurous acid H SO, a colourless, mildly corrosive liquid. This liquid may combine with oxygen in the air, forming the even more irritating and corrosive sulphuric acid (H SO). Sulphur dioxide not only has a bad order, it can irritate the respiratory system. Exposure to high concentration for short period of time can constrict the bronchi and increase mucous flow, making breathing difficult for the elderly and asthmatics. Increased sulphur dioxide contributes to impaired visibility. Oxidized Sulphur dioxide in the form of sulphuric acid easily injures many plant species and varieties. Sulphur dioxide concentration accelerates the corrosion of metals. Sulphur oxides may also damage stone and masonry, paint, STACK GAS DESULFURIZATION6

Stack gas desulfurization is a collective term used to describe the processes involving removal of sulphur dioxide from stack exhausts. IN-FLAME CLEAN-UP: In flame clean-up, also called in-situ clean-up, involves desulfurization of the coal gas as the combustion takes place. In flame clean-up is accomplished by bringing the coal and limestone sorbent into intimate contact with one another to achieve desulfurization and sulphur capture as the combustion gases are being produced. NITROGEN OXIDE Short term exposure of medium to high concentration of nitrogen oxide can measurably decrease lung function. Long term lower level exposures can destroy lung tissue, leading to emphysema. Other effects are damaging the vegetation by killing plant tissue, deterioration of fabrics and corrosion of metals and reduction in visibility.

EROSION & SEDIMENTATION CONTROL INTRODUCTION: The problem of erosion and sediment control has plagued society since civilization. Early land clearing, logging and farming damaged many streams and rivers. Recently, construction activities such as vast networks of highways, sprawling subdivisions, massive shopping centre