Regulators for Southern California have approved an amended National Pollutant Discharge Elimination System (NPDES) permit allowing a Huntington Beach facility to turn seawater into drinking water. Connecticut-based firm Poseidon Resources is proposing the 50-mgd desalination plant on a 12-acre site next to a coastal power plant adjacent to a state beach. Originally allowing the facility to operate in unison with the colocated power plant, the revised permit allows the facility to operate when the power plant is temporarily shutdown or lacks sufficient seawater volumes to meet the desal facility's intake requirements.