The state Department of Natural Resources announced Friday that Gogebic Taconite has closed a 600-foot strip on each side of each private road running through the site.
About 3,500 acres around the site is open to the public through the state's managed forest program. Gogebic Taconite fears protesters could take advantage of that access to harass mine workers as they conduct tests. Republican Gov. Scott Walker signed a law in December that allows the company to create 600-foot restricted zones around private roads on the site.
DNR officials say the public can still venture onto the land to fish and hunt during the November gun deer season.