Loved it, would write up a critique but essentially everything I would say has been said (and quite well i might add) by other reviewers. Really hope you take the time to do a post Jam version of this, it is great as is but with a little push it will be something truly excellent! Also I agree with one of the commenters below (can’t remember who) that this could easily be a prelude to a larger zine module or perhaps expanded itself into a Zine. I’d love to see some small reasons/hooks to come and “get to know” Sumu-7a so I could pepper it into a campaign a few times, make the PCs want to come back or be invested in some way (maybe they spent some money on a “get rich quick” diamond mine asset or something) and then run the ecological disaster scenario you have here…
anyway I’m rambling and I’ve got many more entries to rate, but I had to say your submission was great! easily amongst my favorites of the Jam!