Simplify the following text for a Grade 7 native English-speaking person.
Original: In late December 2006 , the St. Vincent de Paul Society in Saint Petersburg , Florida established an encampment on their property when dozens of homeless moved off of public land across the street from the society .
Simplified: In late December 2006 , homeless people formed an impromptu tent city on the St. Vincent de Paul property in the 1400 block of Fourth Avenue N. of St. Petersburg in Saint Petersburg , Florida when dozens of homeless moved off of public land across the street from the society .