ANCHORAGE, Alaska (AP) – An old mine near where clams and mussels are contaminated with arsenic and heavy metals is being proposed for priority cleanup as a federal Superfund site.

The Environmental Protection Agency has recommended that the Salt Chuck Mine north of Ketchikan on Prince of Wales Island be added to the list of the nation’s most contaminated sites. The copper, gold, silver and palladium mine operated from the early 1900s to the 1940s.

Arsenic and heavy metals from waste rock dumped in the intertidal zone have contaminated salmon and shellfish in Kasaan Bay. The bay is important to commercial fishermen and to locals who rely on its food.

Ken Marcy with the Environmental Protection Agency in Seattle said the concentrations of arsenic found in shellfish harvested in Kasaan Bay are high enough that the federal agency is concerned about the impact on human health.

The Salt Chuck Mine was located on the side of a mountain but processed the ore near the shoreline. The rock that had value was shipped to the Lower 48. An estimated 100,000 cubic yards of rock waste, also called tailings, were dumped in Kasaan Bay.

“That is a huge amount,” Marcy said.

The intertidal area needing cleanup is about 25 acres. An assessment also will be conducted of the mining site and the open mine shaft, the dilapidated mining building, an open glory hole and an open mine shaft, which Marcy said pose obvious hazards.

The area is littered with old batteries that powered the tram at the mine.

Some of the old mine site sits on U.S. Forest Service land. That agency looked into whether there was a party responsible for the cleanup and determined that one no longer existed. The EPA will conduct its own investigation, Marcy said.

The Forest Service has received $1.4 million in stimulus funds for the project.

Neli Nelson, environmental scientist for the Organized Village of Kasaan, said when low tide occurs the scope of the problem is visible.

“When the tide is out and low tide, there is a big spit that is all tailings piles, and all the way back, even where some of the trees are growing up, it is all tailings,” he said.

More warning signs are going up at the mine site and along the beach warning people of the dangers, Nelson said. Even so, some people in the village of about 50 residents still use the area for subsistence, but the number has been greatly reduced, he said.

The area had been popular for collecting clams, crabs and seaweed.

Nelson said the Kasaan tribe has been pushing for the cleanup since the early part of this decade, when the Forest Service looked into turning the mine into a recreation area. Sampling at that time revealed the area was contaminated, he said.

The tribe tries to keep children away from the mine because of the obvious hazards, but they still want to explore, Nelson said.

“The tribe is just very worried about getting these abandoned sites cleaned up,” he said.