Officials of the Massachusetts Water Resources Authority have identified two “hot spots” close to the site of a major water supply pipe break in Boston on May 1 that may be where a critical 10-ft-dia coupling is buried after being forced loose by the rupture. The break generated a two-day boil-water edict. Crews from Barletta Engineering, Canton, Mass., now are designing a trench box to protect the pipe as they begin to excavate, an MWRA spokeswoman told ENR on May 18. The coupling is expected to offer clues to the cause of the rupture, but the agency is not speculating that the connector failed, she says. MWRA is still reviewing design and installation of nearly 100 connectors in its system, and its board is set to soon approve the members and scope of an independent commission that will investigate the cause of the rupture.