The Dover-Plant City area located in eastern Hillsborough County is home to many farms specializing in strawberries, blueberries, row crops and citrus, which rely upon plant irrigation to provide protection from frost or freeze damage during cold events. In 2002, the District adopted Rule 40D-3.600, F.A.C., to establish a North Dover area and a South Dover area for which special well construction standards are applicable. Potable wells constructed in the North Dover area must be cased to a minimum depth of 105 feet below land surface and to 147 feet below land surface in the South Dover area. During 2010, an unprecedented period of actual or predicted freezing temperatures resulted in over 750 potable wells in and around the Dover area experiencing problems or running dry. Sinkholes also occurred because of the significant and concentrated irrigation pumping. Investigation by the District revealed that those wells that experienced failure were not constructed to the casing depths required by Rule 40D-3.600, F.A.C. Further investigation also revealed that the areas affected by large-scale cold protection irrigation in and around the Dover farming community actually extend beyond the boundaries presently designated by the District as the North and South Dover areas. Based upon the fact that the well casing requirements for the Dover area proved effective in preventing potable wells from failing during this recent period of intense water use, the District proposes to expand the North and South Dover area boundaries to include additional surrounding areas that were affected by the cold protection pumping. The current casing depth requirements for each area will remain the same.