Michael Kelin was a scientist on Planet Z02-80535. He didn't think that the planet should be mined, as there were several species native to the planet. He and Erich Strauss often argued the matter.
When the Third Doctor and Sarah Jane Smith arrived, he was impressed at what the Doctor said the native species could do. He was appalled to learn that the slug-like creatures were sentient.
Kelin and the rest of the team were killed when the Builders attacked them. (PROSE: Primitives)