In many countries, people produce power from coal, but it is very dirty and causes acid rain.

在许多国家，人们用煤来生产动力，但是这种方法很脏并且会导致酸雨。

youdao

Brief: The pipe line is needed to dredge when it was blocked. It is very dirty and dangerous and lower efficiency or can not operate by manpower when the pipe line is waste or poisonous.

内容摘要：管道被堵塞需要疏通，如果是用普通的人工清理方法在遇污水或有毒管道时不但脏且是很危险的，而大面积泥土淤积时效率很低或根本无法疏通。

youdao

This jacket is very dirty; give it a good scrubbing.

这件上衣太脏了，洗时要多搓搓。

《新英汉大辞典》

We will also look at trade effluent because it is the dirty water and normally needs to be licensed and manage very carefully.

BBC: Carbon Trust launches scheme to tackle water waste