LAND AND WATER POLLUTION:- Varying degrees of pollution of air, water and land occur in the course of mineral development depending on the stage and scale of activities attained.
While only minor pollution occurs during mineral exploration, more intense air and water pollution emanates from the exploitation stages, particularly if carried out on a large scale.
In Nigeria, the greatest pollution effect comes from a large-scale exploitation of petroleum, limestone and rocks used in the construction works. Large volume of dust from the cement factories and mining operations in the Nigerian limestone quarries are discharged daily into the air. Similarly a lot of air-borne particulate matters are generated by the numerous stone-crushing industries in the country.
When the air is laden with such dust, it causes health hazards for some people. For example, pollution studies around Sagamu and Ewe-koro cement works in Ogun State have shown that several people are suffering from eye pain, and asthmatic attack due to the dust-laden air that prevails within a few kilometers radius of the factories.
DAMAGE OF VEGETATION IN EXPLORATION
Vegetation in form of natural forest or crop plantation is usually the first casualty to suffer total or partial destruction or degradation during the exploration and exploitation of minerals in a locality. The vegetation damage is more extensive at the time of mine development and mining operations and is more expensive when crop plantation is affected.
Recent environmental impact studies of limestone mining and cement industry in Sagamu have revealed a declining kola nut output from the plantations within a few kilometers radius of the cement factory.
This phenomenon is most probably associated with dust pollution as plenty of dust is discharged plants or depend on them for cover, from the affected area. Similarly, the noise generated in the course of blasting, quarrying and crushing can also frighten away part of the fauna in a mining locality.
The plants, animals, soils and water are affected. As mentioned earlier, the vegetation may suffer degradation and eventual death. Some of the animals, especially fish and other aquatic life, as well as small terrestrial animals particularly those that feed on fish or lower plants, may die for lack of food or from contamination with the oil spillage, which normally spread rapidly.
The soil gets soaked in oil and water is covered with oil. Consequently the ecosystem suffers not only disequilibria but also pronounced degradation with dire consequences on the food chain.