LAKE LINDEN (AP) — A government task force is considering three ways to deal with mining waste rock that threatens to smother a natural reef in Lake Superior off the Keweenaw Peninsula.

The Buffalo Reef Task Force has scheduled a public meeting for July 31 in Lake Linden to discuss the options.

Waste rock called stamp sands were dumped into the lake during the copper mining era a century ago. Waves have slowly been carrying them toward the reef, a crucial spawning area for whitefish and lake trout near the mouth of Big Traverse River.

Federal, state and tribal agencies have narrowed a list of options to three. Each offers a different strategy for dredging and disposing of the stamp sands.

A detailed analysis of the options will begin this fall.