A federal study estimates it will cost $8 million to $12 million to clean up lead paint that threatens Laysan albatross chicks at Midway Atoll National Wildlife Refuge.

The study released by the U.S. Fish and Wildlife Service Wednesday says it will take up to six years to clean up lead-based paint from about 86 buildings at the remote island.

Most of the structures were built between 1939 and 1993 when the atoll some 1,200 miles northwest of Honolulu was a U.S. Navy base.

Lead-based paint was used on most of the buildings.

Midway is now a wildlife refuge home to the world’s largest Laysan albatross nesting colony. As many as 10,000 chicks, or up to 3 percent of the atoll’s hatchlings, die from lead poisoning each year.