I don't know anything about this... I'm curious how small could the monitoring station be. Could it be something that could be mobile, like in a trailer or cargo container format, and dropped off at a site temporarily and moved.
0: https://www17.tceq.texas.gov/tamis/index.cfm?fuseaction=repo...
https://syft.com/industries/environmental/mobile-monitoring/
third-party press release:
https://www.azom.com/article.aspx?ArticleID=23241#
Not affiliated, but I did tour their mobile demo van when it was in the US.