Dear Editor, Oh, for the times when common sense could be used versus the language of an ambiguous ordinance.  Using common sense in interpreting the word air gap would be nice.  With 50 or more wells, being on a river, and water catching tanks on the increase in this city, many are going to be unfairly affected. An air gap has a complicated definition, but the danger of a mud hole getting water back into a water system far exceeds an unattached well.  Not so?  Attach a wate ...