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Hardrock gold mining occurred in Juneau from 1880 to 1944. Tailings and waste rock from the mines were deposited into Gastineau Channel and formed beaches along parts of both Juneau and Douglas Island. Mining companies are proposing to reopen some former mines to recover residual gold. Cyanidetreated tailings will be pumped to an impoundment in a nearby mountain valley and an effluent outfall will be constructed in Gastineau Channel. Migratory salmonids, waterfowl, and shorebirds use the channel on a seasonal basis and bald eagles are yearround residents. This study determined concentrations of toxic metals in sediment and resident biota from the channel. Composite sediment samples were collected from 20 locations across and down the channel for an eight km distance. Fish and shrimp were collected by midchannel trawl. Blue mussels and cockles were collected at low tide from six locations from an area composed of old tailings. Freshwater fish were taken from the former Treadwell Mine site on Douglas Island. Mean concentrations of arsenic, copper, lead, and zinc in sediments were higher than concentrations detected in sediments from other locations in southeast Alaska. Lowest concentrations in sediments were found near the mouth of the channel. Mean concentrations of lead, mercury, and zinc in Gastineau Channel were comparable to concentrations found in sediments from South Puget Sound, WA, an area with pollution problems. Tissue concentrations for whole fish from four species of bottom fish indicate that lead, arsenic, mercury, and zinc are elevated. Molluscs also had elevated concentrations of lead and zinc. Concentrations were comparable to those reported in mussels from Commencement Bay, WA, an area of industrial pollution. These data indicate that metal levels in Gastineau Channel are of concern in regards to environmental health and that the combination of tailings and present urban pollution has contributed to the current situation. Proposals for adding metals to the channel through permitted effluent should be carefully considered with respect to these data.