"They've uncovered about 25 sets of bones,'' said Mark Epstein, head of the resource protection and review department in the Ohio Historic Preservation Office. "There's another segment of the project that started over on Wall Street. At least one burial is there, and archaeologists are monitoring what's going on.''

Workers from Applied Archaeological Services found three sets of human remains last week during construction of a sewer line on Spruce Street next to the market. Those discoveries put sewer work on hold Thursday until archaeologists could look for more remains in the trench dug for the 4-foot-wide, 100-foot-long sewer line.

Mary Carran Webster, the city's assistant director of public service, said the discovery of remains yesterday on Wall Street, an alley parallel to High Street, probably would further delay sewer work.

"This is obviously going to be a bigger problem than anybody thought,'' she said. If more gravesites are found on Wall Street, "The sewer project will be closed an additional three weeks until archaeologists can go into each one to see if more bones are there.''

The city and construction crews knew the proposed sewer line on Wall and Spruce streets was on or near the site of the 11-acre North Cemetery, which existed between 1813 and 1873.

Because the project has federal funding, the National Historic Preservation Act required an archaeological review of the site.

"More people are helping with the digging,'' Epstein said. "Ryan Weller (of Applied Archaeological) is still lead archaeologist. He has graduate students at OSU, and this weekend he will have other archaeologists he's contracted with.''

bwilliam@dispatch.com