PDFWAC 173-154-050
Protection of upper aquifer zones.
In any multiple aquifer system, where the department determines that the uppermost aquifers or upper aquifer zone will not sustain large volume groundwater withdrawals without exceeding the safe sustaining yield or causing (1) adverse effects to existing water rights, (2) an unreasonable drop in the water table, (3) permanent damage to the aquifer through depletion of the aquifer or zone, (4) an impairment of the beneficial use of the groundwaters arising from a modification of the water quality, or (5) depletions of spring or stream flows, the department shall require new or additional large volume withdrawals to be restricted to a lower aquifer zone. Permits for withdrawals of water from such lower aquifer zones may specify an approved manner of construction of the withdrawal facilities, including but not limited to, a minimum and maximum well depth, specific casing and sealing requirements, and the construction of monitoring wells for the purpose of periodic measurements in areas where the aquifers cannot be readily monitored through the use of existing wells.