The Sonoma County Board of Supervisors has passed a measure that will mean stricter rules for new wells. The well permitting and oversight regulations, passed Tuesday, are meant to align the county with tougher state groundwater standards. Certain high-volume well users must soon follow new monitoring requirements and, in some cases, pass a closer study to identify possible environmental impacts. Well users whose applications are in the closer analysis category will also have to pay up to eight times the existing rate for an over-the-counter well review. That’s an increase of thousands of dollars. The new rules kick in on May 18th, which is also when Sonoma County’s moratorium on well drilling expires.