3. BACKGROUND
3.6 Impacts of resource extraction industries
3.6.1 Air pollution
The most evident impact from aggregate, stone, and industrial mineral mines is degraded air quality, and associated health effects, resulting from airborne emissions (Laister, 2002;
van Oss and Padovani, 2003; Blodgett, 2004; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007). With regard to mines air pollution is mainly due to emissions of gases and particulate matter, which is classified as dust (Laister, G, 2002; van Oss and Padovani, 2003; Blodgett, 2004; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007). Opencast mining and quarries cause greater air pollution, as they are known to emit gaseous pollutants and dust (Laister, G, 2002; van Oss and Padovani, 2003; Blodgett, 2004;
Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007). Resource extraction industries such as these create air pollution problems not only within the mining and quarrying premises but also in surrounding residential areas as they affect air quality and have devastating implications on health.
Gaseous emissions may be generated during the construction and operation of a mineral resource extraction industry (Laister, G, 2002; van Oss and Padovani, 2003; Blodgett, 2004; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007). Gaseous emissions reduce the air quality and have huge impacts on human health particularly where emissions are harmful gases. The "impact can be extremely serious where emissions contain harmful compounds such as dioxins (Laister, G, 2002; van Oss and Padovani, 2003; Blodgett, 2004; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007). The typical gaseous emissions from resource extraction industries include Nitrogen Oxides (N20 ) , Sulphur Dioxide (S02), Carbon Oxides (CO and CO2) and Methane (CH4) (Laister, G, 2002; van Oss and Padovani, 2003; Blodgett, 2004; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007). Exposure to these gases can result in headaches, nausea, tiredness and fatigue. However, in resource extraction industries other emissions are present as well, such as volatile organic compounds (VOC's), which are considered to be human carcinogens (Bloemen and Bum, 1993; Kerfoot, 1993; El-Fadel et ai., 1997). Similarly, acute effects of VOC's at high levels include: eye, nose and throat irritation, dizziness, headaches, loss of short term memory, fatigue and nausea (Bloemen and Bum, 1993;
Kerfoot, 1993; El-Fadel et ai., 1997). Emissions of these gases considerably affect the social environment as the well-being of individuals is threatened. Furthermore, many
mines especially those operating in oil extraction, such as the Niger Delta in Nigeria, produce large red flames from the burning process, which leads to CO2 and CO discharge thereby affecting the air (Aigbedion and Iyayi, 2007). Burning results in gaseous and particulate matter emissions which are discharged into ambient air (Gosar, 2004;
Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007). Resource extraction industries that are focused on extracting industrial minerals, like perlite and silica flux, can cause silicosis on prolonged exposure (van Oss and Padovani, 2003; Blodgett, 2004; Gosar, 2004; Kitula, 2006; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007).
As a result of gaseous emissions, tainted air is taken into the body and can consequently deteriorate an individual's health. Gbadebo and Bankole (2007) explain that during inhalation and exhalation, these pollutants can cause serious damage to the lungs and tissues of human beings. Gbadebo and Bankole (2007) explain that the pollutants emitted from resource extraction industries enter the numerous tiny air sacs inside the lungs and also the blood stream which not only affect the lungs but may have disastrous impacts on other organs (Gbadebo and Bankole). Gbadebo and Bankole (2007: 39) elucidate that:
"many of the possible serious health problems of these airborne dust pollutants on human include asthma, irritation of lungs, bronchitis, cancer, pneumonia, decreased resistance to respiratory and early death". These gaseous emissions present serious problems for the social environment, since emissions from these resource extraction industries affect the well-being of many individuals. However, Aigbedion and Iyayi (2007) explain that the bio- physical environment is also impacted on by these emissions, as these gaseous emissions contribute to global warming, since these gases are considered to be green-house gases.
Thus these gaseous emissions pose serious harm to both the social and bio-physical aspects of the environment. However air pollution with regards to resource extraction industries is not only attributed to gaseous emissions but also to the increase prevalence of particulate matter (dust).
A large degree of dust from resource extraction industries is discharged daily into the air as a result of dust producing operations namely drilling, blasting, hauling, loading, transporting and crushing (van Oss and Padovani, 2003; Blodgett, 2004; Gosar, 2004;
Kitula, 2006; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007; Singh and Pal, 2010). Dust sources in mines can be categorised as primary sources that generate the dust and secondary sources which disperse the dust, known as fugitive dust, and carry it from place to place. In terms of primary sources, generation of dust can be explained as resulting
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from poorly monitored crushers and non-compliant operations (Blodgett, 2004). Secondary sources resulting in fugitive dust is dust which is blown from the uncovered or partially covered dump trucks and also resulting from piles of sand and gravel at the construction sites (Blodgett, 2004; Gosar, 2004; Kitula, 2006). This can be observed in the case study as dust emitted from the Ridgeview Quarry is very visible. Aigbedion and Iyayi (2007) further explain that in the same way, a large number of air-borne particulate matters are created by the many stonecrushing industries. Other resource extraction industries that are focused on gypsum extraction can also produce very fine gypsum dust that can irritate the lungs and mucus membranes (Blodgett, 2004; Gosar, 2004; Kitula, 2006). Exposure to air laden with dust leads to health hazards such as respiratory problems, eye problems and asthma (Blodgett, 2004; Aigbedion and Iyayi, 2007). The digging, blasting and drilling in mineral extraction industries emit dust particles of various sizes into the immediate atmosphere, which can be inhaled by humans. Most of this dust is usually made up of Silica (occurring as Silicon Dioxide Si02) which is detrimental to the health of individuals (Singh and Pal, 2010).
Apart from direct health problems to human beings, dust not only deteriorates the social environment but also creates the serious problems for the bio-physical environment.
Adverse effects of airborne dust pollution on the bio-physical environment, in general, are ozone layer depletion, green house effects, stunting of plant growth and acid rain (Kerfoot, 1993; van Oss and Padovani, 2003; Blodgett, 2004; Gosar, 2004; Kitula, 2006; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007; Singh and Pal, 2010). The effects of dust clouds and dust deposits are both visible and tangible in communities around industrial activities or construction sites (van Oss and Padovani, 2003; Blodgett, 2004; Gosar, 2004;
Kitula, 2006; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007; Singh and Pal, 2010). The dust can pollute nearby surface water and stunt crop growth by shading and clogging the pores of the plants (Gbadebo and Bankole, 2007; Singh and Pal, 2010). Dust from mines and quarries settle on the soil which increases the soil pH, thereby affecting seed germination (Singh and Pal, 2010). Furthermore, Amira (2002 cited in Gbadebo and Bankole, 2007) explains that dust from mines and quarries changes the salt content of water, consequently disrupting aquatic communities and decreasing the quality of water used for drinking and irrigation purposes. Gbadebo and Bankole (2007) further explain that dust is capable of increasing water turbidity and reducing light penetration and further contribute to great water hardness or elevation of carbon dioxide which will increase other
pathological conditions (Kerfoot, 1993; van Oss and Padovani, 2003; Blodgett, 2004;
Gosar, 2004; Kitula, 2006; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007).
Mining and quarrying operations often contribute to the greenhouse effect. The greenhouse effect is a natural phenomenon which refers to the increase in the earth's surface temperature due to the presence of certain gases in the atmosphere (Kerfoot, 1993; van Oss and Padovani, 2003; Blodgett, 2004; Gosar, 2004; Kitula, 2006; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007; Singh and Pal, 2010). There is great concern that this phenomenon is being altered and enhanced by greater emissions of gases caused by human activity, such as those relating to resource extraction industries. In many resource extraction industries, burning of fossil fuels produces CO2, a gas that is linked to global warming through the greenhouse effect (Kerfoot, 1993; van Oss and Padovani, 2003;
Blodgett, 2004; Gosar, 2004; Kitula, 2006; Aigbedion and Iyayi, 2007; Gbadebo and Bankole, 2007; Singh and Pal, 2010). The combustion of fossil fuels such as coal produces gaseous emissions of Sulphur Dioxide (S02) and Nitrous Oxides (NzO) that are responsible for the production of 'acid rain' and 'ground level ozone', which negatively impacts the social and bio-physical environment (Kerfoot, 1993; Blodgett, 2004; Gosar, 2004;
Aigbedion and Iyayi, 2007). Acid rain occurs when SOz and NzO gases react with water, Oxygen and other chemicals in the atmosphere and consequently form acidic compounds (Kerfoot, 1993; Blodgett, 2004; Gosar, 2004; Aigbedion and Iyayi, 2007). Ground level ozone is formed when NzO gases react with other chemicals in the atmosphere and produces smog over cities (Kerfoot, 1993; Blodgett, 2004; Gosar, 2004; Aigbedion and Iyayi, 2007). The emissions of SOz and NzO are classified as trans-boundary air pollution because the environmental impacts from the production of these gases are not restricted by geographical boundaries (Kerfoot, 1993; Blodgett, 2004; Gosar, 2004; Aigbedion and Iyayi, 2007). Thus air pollution is not restricted to a certain area but can migrate and cause problems for many individuals.
These high levels of gaseous emISSIOns and suspended particulate pose serious implications on both the social and bio-physical environment, as the health of individuals is compromised and the natural environment is seriously deteriorated. However resource extraction industries are not only associated with air pollution but its activities also contribute to water pollution.
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