Richard and Camilla Coniglio are greeted at Washington, D.C., by Melanie Beasley, Amtrak passenger representative, and Roger Lewis, Amtrak president. Mr. and Mrs. Coniglio are Passengers 3,000,000 and 3,000,001 in the Metroliner Service's first 30 months of operation. Richard Coniglio is a 25-year-old pharmacist of North Bergen, N.J.