Lower East Side For a Frail Old Tenement, a Fortifying Dose of Goop Stephen Chernin for The New York Times Workers drilled 1,435 holes into the structure, and pumped in 1,280 gallons of the secret stuff. By EVE M. KAHN Published: May 22, 2005 A year ago, owners of condominium apartments at 241 Eldridge Street heard dire news. Cavities were