The envisionment of TK is to bring you what was promised by GSC for STALKER: Shadow of Chernobyl, instead of the gutted retail release we were left with. TK aims to cover every aspect imaginable from gameplay intended to genuinely scare the player, to graphics for the absolute best visual experience, cut mutants, absolute realism, optimisations, stability, and a complete game mechanics overhaul, all without breaking the story. The idea is to present the player with a complete retail experience for the purist that liked SoC but wished it was far more fleshed out. In no way what so ever does TK try to be like old beta or alpha builds of SoC, TK aims to enhance everything SoC already has - nothing more, nothing less.
Lots of under the hood changes have been made for the upcoming TK release, including as you see here the chance to bump into ecologists. I always found it really disjointed that ecologists are supposedly studying the zone yet the only signs of them in vanilla SoC are of them getting their arses handed to them in rostok, dead (radar) or cowering in the bunker at yantar.. so much for exploring and understanding the zone.
Now you won't only just occasionally run into them but sometimes you may even come across them exploring the zone with a somewhat randomised guard escort.