Just a few months ago, biotechnology incubator ACET was celebrating the future of a new $8 million facility it planned to build here. It also would be the first new commercial construction on former Navy land. Now it looks as though the incubator -- once tagged a model project for its reuse of Navy land and potential for generating thousands of highly skilled jobs -- might never get off the ground. ACET learned this week that the U.S. Department of Commerce, which gave it $6.4 million in 2002 to build the new facility, will terminate the incremental grant, of which $2.5 million already has been allocated.