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}} The New Idria Mercury Mine encompasses 8,000 acres of land in the Diablo Mountain range, incorporating the town of Idria in San Benito County, California. Idria, initially named New Idria, is situated at and 2440 feet (680m) above mean sea level. The area was, in the past, recorded in the US Census Bureau as a rural community; however, Idria has become a ghost town since the closing of once lucrative mining operations in the early 1970s.〔New Idria, California〕 In 1990, the United States Environmental Protection Agency (EPA) investigated the mercury contamination level in soils, groundwater, surface water, and air of Idria, and concerned with the impact that the mining industry had had on the local environment. However, the contamination was not ranked high enough to be listed on the EPA’s Superfund Site List, nor its National Priorities List.〔http://www.new-idria.org/〕 On March 10, 2011, after the site had been reassessed in 2002 along with an expanded site in 2009, the EPA finally proposed adding Idria to California's Superfund List. Mercury, along with heavy metals and acid mine drainage, were found in nearby San Carlos Creek, Silver Creek and a portion of Panoche Creek at high toxic level to aquatic organisms and nearby populations. The contamination was also shown to be potentially threatening to habitats extending to the San Joaquin River and San Francisco Bay.〔http://yosemite.epa.gov/R9/SFUND/R9SFDOCW.NSF/3dc283e6c5d6056f88257426007417a2/54dc8315ad9b2118882578640082622e/$FILE/NIMM3_11_294kb.pdf〕 ==History== The New Idria Mercury Mine was claimed in 1854, with the first brick furnace built in 1857. During the California Gold Rush, mercury was the key component to extract Gold from ores. Mercury, a major component in the cinnabar-rich rocks in Idria, could be economically extracted to support nearby gold mining and processing operations. Idria eventually became the second most productive mercury mine in North America, producing over 38 million pounds of mercury during its lifetime. Mercury mining operations ceased in 1972, with the closure of the New Idria Quicksilver Mining Company.,〔〔 However, the environmental consequences of mercury mining remained well past the abandonment of the town. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「New Idria Mercury Mine」の詳細全文を読む スポンサード リンク
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