A small, nondescript parking lot at the corner of Fourth and Gaskill Streets became the subject of debate at Friday's meeting of the Philadelphia Historical Commission when commissioners said it didn't matter that the site — like all sites within the Society Hill Historic District — held archaeological potential.

"It doesn't matter if there are archaeological remains," said Leonard Reuter, deputy city solicitor and the commission's attorney. He said the commission's authority was limited to reviewing plans, not imposing its will.

In the end, the commissioners decided the legalities of the Society Hill Historic District precluded them from acting.

At issue was whether the commission would exercise its full authority over the narrow lot, which owner Jefftown Village LP is seeking to grace with a townhouse.

Jefftown attorney Carl Primavera and architect Stuart Rosenberg argued there is a contradiction contained within the lot's designation as "non-contributing" to the district's historic fabric, and its parallel listing as having "archaeological potential."

Douglas Mooney, president of the Philadelphia Archaeological Forum, flatly said there is "no contradiction." The lot is non-contributing with regard to its aboveground architecture — there is none — and its belowground archaeological potential is unexplored and should be protected.

"You must have direct knowledge of what's below ground on that site" in order to assess its potential, Mooney said. Absent direct examination, all discussion of it "is meaningless."

The nominating application that led to the formation of the Society Hill Historic District in 1999 seems fairly clear on the archaeological importance of the neighborhood. In fact, "archaeological potential" is one of the factors that makes the district historic.

The district's nominating application states: "As demonstrated by archaeological and construction excavations and by the development history of Society Hill, archaeological features survive in the basements and under the streets, gardens, and yards of this district. Above and below ground, Society Hill meets the criteria for designation as an historic district prescribed by the city's Historic Preservation Ordinance … of the Philadelphia Code."

Jonathan Farnham, commission executive director, said there have been at least five times the commssion has considered situations similar to the Fourth and Gaskill parking lot. Each time, he said, the commission has chosen not to exercise full authority over non-contributing sites with "archaeological potential."

Mooney, who sits on the commission's historic designation committee, said this practice "is potentially placing archaeological resources at risk."

"The entire district is listed as having archaeological potential at the time of nomination," he said. To ignore or diminish that "calls into question the legitimacy of the entire district."

Patrick Grossi, advocacy director of the Preservation Alliance for Greater Philadelphia, said the question is important to resolve: Does the commission take archaeological potential seriously enough to bring its full authority to bear in regulating development and construction?

The commission could, for example, require developers to bring in archaeologists to monitor development. (There is no archaeologist on the commission staff.)

"What is the value of listing archaeological potential if there's nothing actionable about it?" Grossi wondered.

Commissioner Emily Cooperman said the issue is "fairly pressing and needs to be addressed."

But in the end, the commission ignored the recommendation of its archaeological committee to "retain full … jurisdiction over potential archaeological resources at the site, pursuant to criterion."

No vote was taken. The commissioners deferred to legal counsel, as member John Mattioni suggested at the meeting.

"Let's get on with it," Mattioni said.