Of all the mining colonies in the Terminus Systems, Irunel (not to be confused with the volus homeworld) is what can only be called hostile. Not because of native life - it has none - but because of the sheer acidity of its environment. While its atmosphere is rich in oxygen, breathing it for a long period of time is enough to cause acid burns within most species' lungs - the only real exemption being krogan. Pockets of sulfuric acid mixed with red phosphorus can be found throughout the crust, making mining difficult.
What draws people to this place is the riches contained within the rocks: the planet has massive deposits of platinum. Unfortunately, due to the chance of igniting a pocket of phosphorus, mining must be done with mechanical drills (and occasionally explosives) rather than lasers.
Culture-wise, 'melting pot' is putting it mildly. The local dialect is a mish-mash of Thessian basic, Tuchankan standard, volus trade basic, and Palaven standard.