Orn Lote is the engineer on Tagra IV responsible for the barystatic filters that keep the planet's heavily polluted air breathable, whose failing reactor the Enterprise comes to repair in True Q.
Orn Lote appears in the sixth-season episode True Q. The people of Tagra IV have chosen to scrub their poisoned atmosphere with a network of barystatic filters rather than stop polluting it, and Lote is the official who manages the system.
He asks the Enterprise for help when one of the reactors powering the filters becomes dangerously unstable, and works with Geordi La Forge on repairs. The effort fails and the reactor heads for a catastrophic breach that would kill a large part of the population.
The crisis is ended by Amanda Rogers, the young intern revealed to be a Q, who halts the explosion and then cleans the planet's entire atmosphere, the act that settles her decision to accept what she is.