Rarely does a federal policy have as direct a potentially positive impact on the South Fork as does one put in place earlier this year by President Obama to allow some children of undocumented migrants a way to avoid deportation and work here legally. Called Deferred Action for Childhood Arrivals, it allows immigrants 30 and younger who have lived in the United States for five or more years to apply for a Social Security number and a two-year, renewable work permit.