Remove beards on mussels, and scrub shells with a brush. Discard opened, cracked, or heavy mussels (they're filled with sand). Set aside.
Place broth in a large saucepan, and bring to a boil; add rice, curry powder, and salt. Cover, reduce heat, and simmer 15 minutes. Add mussels, peas, seafood, and pimiento; cook 5 additional minutes or until mussels open and rice is tender. Discard unopened mussels.