Bad odour coming from Sewage Treatment Plant built in residential complex

Sewage treatment Plant in Pune

I would like to let you know that i have purchased a flat in residential complex "Sukhwani Scarlet" constructed by Sukhwani Contructions at Kesnand Road,wagholi,Pune-412207 ,got possession in Aug-2015 and residing since end of November 2015. They have constructed a sewage treatment plant(STP) just next(only 3-4 mtrs away) to my building which is functional since begining. Initially it was totally closed from top by RCC and no issue with the STP as such.But in the month of May/June 2016 they have broken down the RCC cover from top.Now since the STP is open bad unbearable smell keep on coming from the STP on everyday basis.Due to this bad smell neither i can open the door of my balcony nor the windows.It has created a very unhealthy environment to stay. It's being a serious health concern for my family i hereby request you to provide guidance.