Judge refuses to block digging at lithium mine on Nevada-Oregon line SCOTT SONNER View Comments RENO, Nev. (AP) — A federal judge has denied environmentalists' request for a court order temporarily blocking the government from digging trenches for archaeological surveys at a mine planned near the Nevada-Oregon line with the biggest known U.S. deposit of lithium. U.S. District Judge Miranda Du said in an 11-page ruling late Friday in Reno that four conservation groups failed to prove the trenches planned across a total of one-quarter acre (.10 hectare) would cause irreparable harm to sage brush that serves as critical habitat for imperiled sage grouse.