This point is very closely related to the previous one on waste management and could be easily categorized as so. The truth is that they are not. Pollution refers to the creation of any form of disturbance or inconvenience to the environment and especially the neighbourhood. There are various forms of pollution identifiable with construction sites, and which should be well thought out at the very beginning of the process. These include the following:
· Air pollution: One of the most common forms of air pollution in construction sites is through dust. This is especially common in projects where earthworks is taking place. It is also common in processes like concreting, whereby cement dust is let out into the atmosphere. Burning of waste materials is also a common source of air pollution. While dust is trapped with relative ease, for example by the use of netting, smoke and other such fumes is hard to control and should therefore be avoided.
· Sound pollution: Usually very common with construction plant and other such equipment, but also during construction processes like demolition and rock blasting. Good hoarding will curb a reasonable percentage of the noise, but not entirely. Use of less noisy plant and less chaotic construction processes is among the best solutions around the problem.
· Water pollution: This is common where effluent is directed into water bodies before it is treated. The act of letting surface run-off sweep through the site and proceed into rivers should be prevented by diverting such run-off by use of trenches. Effluent laden with petroleum residues should be treated before letting it out of site. Human waste disposal should also be such that it does not compromise the wholesomeness of water sources. A good example is where pit latrines are sunk in close proximity with water wells.
Other disturbances like heavy vibration compaction works or crane jibs hanging over residential areas can also be considered as forms of pollution, as they create a form of disturbance, for example psychological. Pollution is another very keenly watched aspect in any proposed construction projects and can hinder approval of building plans as well as stall an already started project.
One of the determining factors of the allowable levels of pollution is the kind of environment that the construction is taking place. Residential areas are more delicate than commercial centres and even lesser for lone, remote sites. Whichever the case, utmost care should be taken by the site manager to ensure that only the inevitable forms of pollution are sent out to the environment.