The Holbrook town clerk administered the oath of office Tuesday to Benjamin Ecord, the town’s new superintendent of public works, with his family and public works employees in attendance. Ecord has filled in as superintendent since Tom Cummings, who held the job for 58 years, retired at the end of June. “He’s doing a great job,” said Assistant Town Administrator Marjorie Godfrey. Ecord previously worked as supervisor of the public works crew. William Phelan, the town administrator, said the Board of Selectmen will likely sign his contract at its next meeting in January.