It is impossible to track sources of pollution so using drains for disposal often hides an automobile mechanical shop's wastes

True.

Although some sources of pollution may be tracked, drainage systems of some companies and corporations are used to hide the waste that they dispose off. This practice may be harming a lot of our water supplies around the world, but depending on the rules of their country, there is really nothing we can do but do our part by fighting for a cleaner disposal of their waste.

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