I am currently pursuing my UG in Bioinformatics and I am looking for masters in environmental science/studies. I need to know whether it is feasible considering my UG degree, if not please help me with some pre-requirements that are essential so that I can pursue a masters degree in environmental science/studies...

You need to be more specific? You need to contact potential universities and ask them directly as well. Look at course requirements online also.

Hi, the University of East Anglia offers environmental science masters courses that might be of interest as they offer many module options to choose from, spanning from physical science, computer science to social science.

I think with your UG degree you could get on a course and then you can choose what direction you want to go in. The university seems to have a steady stream of funded PhD opportunities in this subject area, (perhaps something for the future).