In the TNG Episode "Home Soil", the crew visit a terraforming group of scientists.
The episode explains the terraforming process which is similar to the Genesis Project: select an appropriate planet, confirm no existing life exists, etc.
From the transcript:
We take a lifeless planet and little by little transform it into an M
class environment, capable of supporting life. Terraforming makes you
feel a little god-like. The first phase involves selecting the planet.
That's very important. It must have the right mass and gravity, the
correct rate of rotation, and a balanced day and night. The planet
must also be without life or the prospect of life developing
naturally. The Federation determines if that's so. Then, we take over.
This station is phase two. Phase Three involves water. Usually we
create basins using hydraulic landscaping, but the water on this
planet is subsurface, and extremely high in salt content. We are just
about to begin pumping and filtering the water, removing the salt,
oxygenating and replacing. Next, we introduce micro-organisms, and
when the process is complete eventually, we'll have a lush, arable,
One of the scientists calls herself the "Gardener of Edens."
The scientists also exhibit similar characteristics to the group on Regula 1: passion, obsession, impatience, and deceptiveness.