I guess it depends on framing. (Spoilers ahead for anybody who hasn't read the book yet.) The mining did not have a direct impact upon the environment. But, the mining of course depended upon the presence of the spice melange and of the sandworm makers. This "natural" process which produced the spice was consuming and trapping the lion's share of the water on Arrakis, keeping the planet in an otherwise "dead" state. The terraforming of Arrakis into a more habitable planet would decimate the spice production - and thereby the spice harvest - and so had no support or interest from anybody except the Fremen. So, while it's not exactly accurate to say that the planet was being mined to death, it would be accurate to say that the planet was being kept in a dead state by mining interests, which is essentially the same thing in principle.