Napa County is looking for ways to fund its state-mandated Groundwater Sustainability Agency and could look to well-water users. Since 2019, the county has spent $8.7 million in general fund money on the groundwater agency. California law allows for a fee on groundwater extraction to pay the bills, a county report said. On Tuesday, Napa County supervisors, sitting as the Groundwater Sustainability Agency board, are to discuss funding options. They will use a report by SCI Consulting Group as a starting point.