Browsing Publications by Author "Thomas, B"
The effects of placer mining on the environment in Central AlaskaWolff, E.N.; Thomas, B (University of Alaska Mineral Industry Research Laboratory, 1982)Within the Tolovana Mining District, as a result of placer mining, 800 acres of land have been disturbed (0.25% of the land area) and 4 million cubic yards of much have been transported down the Tolovana River through the subsiding Minto Flats. This has increased the rate of sedimentation of the lakes adjacent to the Tolovana River. Mine tailings are about 50% revegetated by natural species. Approximately 60 million cubic yards of muck must be removed to mine the Livengood deposits. A large area of settling ponds will be needed if the deposit is stripped by hydraulic means, or a large area for stacking overburden if mechanical stripping is required. The Crooked Creek area, mined for 80 years has 1,900 acres disturbed (0.7% of the land area) and 200,000 cubic yards of much has been stripped. No correlation is apparent between mining and the non-anadromous fish population, although sport fishing is considered by some to be not as good as a result of mining. Portions of the stream system observed to be impacted with mud showed evidence of having been periodically flushed out. Slave analysis and trace element analysis were applied in an attempt to trace sediments back to their sources, but were not successful. Mining is the pioneer industry around which much of the State of Alaska developed. The transportation network required by the mining industry benefits sportsmen, the tour industry, and directly increases the value of adjacent land. The profit from mining brought much of the early population to the state, and will be a steady source of revenue in years to come.