SAN FRANCISCO (AP) – The California Supreme Court is set to rule on the legality of the state’s ban on the use of suction dredges to extract gold from rivers. At issue in the decision expected on Monday is whether the ban is overruled by a 19th century federal law that allows mining of gold and other minerals on federal land. Suction dredges are powerful underwater vacuums that suck up rocks, gravel and sand from riverbeds to filter out gold. Miners say the state’s ban on dredges amounts to a ban on gold mining because mining by hand is labor intensive and makes the enterprise unprofitable. State officials say suction dredge mining risks killing fish and stirring up toxic mercury. They say they have a right to protect the state’s environment that is not pre-empted by federal mining law.