Problems due to STP

What are the predictive problems that can arise in the surrounding area of a STP?

My house is under 500 m of distance from a new STP plant. At night, strong foul smell disturbs us and even the noise of the plant sometimes. We are really worried about the hazardous effects the plant could have on our body due to such prolonged exposure to the smell.

As I was unsuccessful in finding some proper guidelines for the minimum distance of the plant from residence , I would really appreciate any kind of information regarding the same. Also, what kind of bacteria / germs can manifest in the surrounding region? Thank you so much!