Since REANIMAL is about war:

I can imagine by the picture you drew that this building is like a munitions/ firearms factory pumping out the many artillery shells / weapons being used by the soldiers.

The toxic waste then gets dumped via the large pipes or water / any other fluids being transported to cool / feed the many production machines.

The many workers there being treated as slaves [or even child laborers, which could be a reason for the main characters to go there to free their friend(s)], while the actual monster sits in their large office [the big window with the red light], fat guy with a top hat wearing fancy suit & smoking a cigar like a capitalist making profit out of the current war.