SAN DIEGO ---- Regional planners are polling San Diego County residents to see if they would support a special "quality of life" tax to fund beach-sand replenishment, open-space purchases, habitat restoration and water-quality programs, an agency official said Thursday. The funding source could come in the form of a sales, property, hotel or rental-car tax, and could appear on the county ballot in 2008, said Rob Rundle, principal planner for the San Diego Association of Governments, the county's regional planning agency. Rundle said results of the telephone poll of 2,000 county registered voters will be reported to the association board...