This Thursday and Saturday, about 600 volunteers will fan out across the county in the annual Days of Caring event that launches the fund-raising campaign for the United Way of Addison County. The goal remains the same, $775,000, as it has been over the past couple of years, but the challenges are bigger than ever: on top of a lackluster economy that has yet to recover from the Great Recession of 2007-08, are disaster relief efforts to help those individuals and communities devastated by the flooding of Tropical Storm Irene.