The Mutual Burial Ground of Kensington, long gone and largely forgotten, has been recommended for historic certification by a panel of the Philadelphia Historical Commission.

At a meeting Wednesday, panel members heard a rare appeal not on behalf of a memorable structure, but for preservation of what cannot be seen at 1834-48 Frankford Ave.

Where two old brick garages now stand, one housing the soon-to-shutter Sculpture Gym, Point Breeze developer Ori Feibush wants to build about 40 residential units.

But the site lies above a once-active but long-abandoned cemetery that served those who lived in and built 19th-century Kensington. As many as 10,000 may lie throughout the grounds, which stretch west from Frankford Avenue. The cemetery was in use from the 1820s until the end of the 1860s.

Kensington historian Ken Milano filed an application to preserve the site. Feibush, who has a demolition permit, is opposing the designation.

The commission staff has said it does not have the authority to block demolition.

At Wednesday's meeting, Sean P. Whalen, Feibush's attorney, said Milano was acting out of "personal animus" in an effort to stop development in the quickly gentrifying area.

Milano, who has researched his neighborhood for decades and has written several books on local history, said that is not the case.

"I wrote this nomination to preserve the ground under the building, not to stop development," he said, adding that he believed it important "to see if we could get information about our community" via archaeological analysis.

Aaron Wunsch, an assistant professor in the University of Pennsylvania's historic preservation program, told the commission that "a mutual or social cemetery is a rare breed indeed."

Such burial grounds were the product of laboring classes' moving into the city, building neighborhoods, manning burgeoning workplaces along the river, and sharing the costs of a final resting place.

"If the Mutual Burial Ground [of Kensington] does survive," he said, "it could be the last remaining example of the type."

The problem is that no one knows what lies below ground. Feibush maintained there is no evidence anything is there but dirt and old oil tanks.

Jed Levin of the Philadelphia Archaeological Forum said it is impossible to tell what might lie below the surface without looking. Designation, he said, would not only make that possible, but would protect the ground and the information it contains "so that we're not back here in 20 years" arguing over another development.

The full Historical Commission will consider the recommendation at its July meeting.