From the wind farm drive northwest until you reach a fork at some Remnant ruins, at which point take the northeastern branch. When you hit a second fork, turn northwest again and drive up the mountain road until you get some comm chatter, which starts this quest. This should occur just past the Angaran town where the quest "Something in the Water" starts.
To reach the navpoint for this S.O.S. keep following the road past the Angaran town until you reach the more open expanse of Kurinth’s Valley. Drive around a toxic lake, then over (or around) some small hills north of the lake, after which continue northwest down into another valley housing a toxic lake. When you reach this valley turn west and make your way for one of Kadara’s signature elevated structures, where the navpoint indicates the S.O.S. is coming from.
Cross a bridge leading to the structure’s outer door, head through two doors and beyond you’ll find two burnout Outlaws hanging around, in no apparent need of aid whatsoever. Scan them to confirm that they are… ah… "cognitively impaired", and if you need more evidence, read the nearby datapad. Worse than simply being druggies, they’re also bigots against the color purple! Chat with them and they’ll tell you the nature of the distress call, which isn’t much of an emergency at all. Finish your conversation with them and this quest will end, netting you 270 XP. As another bonus, you can scan an Adapted Initiative Core Tech device as you leave for some juicy Research Data.
Note: This quest seems to end prematurely. In the isolated refugee structure where the quest "Task: Broken Family" takes place you can get some UV Lights from the Salarian refugee, which you can then give to the Outlaws in this quest. You can also talk to a Turian refugee to learn about another afflicted refugee who needs antibiotics, which the Outlaws offer you if you replace their broken UV light. It seems, then, that you should be able to take some of their plants and give them to the refugees, but you can’t actually do so, nor do you have to give them a UV light to end this quest satisfactorily.