Second Helpings

People always remain people. Faith in a bright future can sometimes deceive even hard pragmatists, but when only one tiny step remains to the edge of the abyss, Haviland Tuf, a brilliant ecological engineer, comes to the rescue.
Tuf returns to the planet S'uthlam after 5 years to pay half of his debt and at the same time see how his ecological prescriptions are being carried out. But, as is well known, in reality it is practically impossible to take all initial conditions into account correctly. And so Tuf has to solve new problems.