Installed a STP in apartments, faced with odour issues - Is there any way to prevent odour rising from the equalization tank?

Hello

We have recently set up a STP in our apartment. It is very useful, amount spent on water tankers has reduced to a good extent. However, the problem is the odor which rises from the equalization tank of the STP. Is there any way by which this odor can be prevented from wafting into the homes located near the STP?