The scope of the project has grown during a decade of planning to include recognition of the nine slaves Washington kept at the President's House near Independence Hall.
"It certainly will tell the story of achievement. This is where the first two American presidents lived and worked," Rendell said at a news conference. "But it is also a story of infamy. The first president of the United States had nine slaves, two of which had to flee to get their own freedom."
A decision by the DRPA is expected Friday. Rendell serves as chairman of the bistate agency and said he considers the grant a wise use of agency funds, given the interest in historical and cultural tourism. Earlier funding came from city and federal sources.
The project is a joint venture of the city and the National Park Service, which operates the surrounding Independence Mall Historical Park. Officials expect it to open in the fall of 2010.
Mayor Michael Nutter and his predecessor, John Street, who had pushed the project, joined Rendell at the podium. They noted that the announcement comes just a day after the nation inaugurated its first black president.
"This project (now) has even greater significance," Street said. "No one had any clue that we would be swearing in the first African American president ... in the history of this country."
Nutter has asked President Barack Obama to visit the site, he said.
Washington and John Adams each lived at the house when Philadelphia was the nation's capital between 1790 and 1800. Only Washington kept slaves there.
Under a revised plan drawn up after an archaeological dig found intact ruins in 2007, visitors will be able to view a slave passageway, bowed window and other remains.
"In this intense historical and cultural area, there was nothing for African-Americans," said Venus Foster, 51, of Philadelphia, who belongs to an activist group called Avenging the Ancestors. Now they are eager to tour the President's House and the slave remains, she said.
Controversy over the slavery issue was sparked when city and federal officials began planning a new home for the Liberty Bell, itself an important symbol to abolitionists. Some historians and black groups were outraged when it was revealed that the entrance to the new pavilion was near where the slaves once lived.
In 2002, Congress directed the National Park Service to "appropriately commemorate" the slaves.
