Required for 3' polyadenylation of the 5.8S and 25S rRNAs as a prelude to their degradation in the exosome. Involved in the nucleolar organization to ensure faithful chromosome segregation during mitosis. ATP + RNA(n) = diphosphate + RNA(n)-3'-adenine ribonucleotide Heterooligomer. Interacts with air1. Belongs to the DNA polymerase type-B-like family.