Environmental concerns Butte, Montana
because water contains high concentrations of metals such copper , zinc, berkeley pit listed federal superfund site.
after closure of berkeley pit mining operations in 1982, pipes pumped groundwater out of pit turned off, resulting in pit filling groundwater, creating artificial lake. 2 years later pit classified superfund site , environmental hazard site. water in pit contaminated various hard metals, such arsenic, cadmium, , zinc.
it not until 1990s serious efforts clean berkeley pit began. situation gained more attention after many 342 migrating geese chose pit lake resting place, resulting in deaths. steps have since been taken prevent recurrence, including not limited loudspeakers broadcasting sounds scare off waterfowl. however, in november 2003 horseshoe bend treatment facility went online , began treating , diverting of water have flowed pit. berkely pit both superfund site , tourist attraction, viewable observation deck. per 2014 report, scientists believe berkeley pit may reach critical water level—potentially contaminating silver bow creek—by year 2023. beginning in 2019, montana resources , atlantic richfield co. ordered environmental protection agency begin treating water pit, discharged silver bow creek @ rate of 7,000,000 gallons (26,000,000 l) per day. nikia greene, epa project manager mine flooding, assured in 2014: pit giant bathtub. there’s hydraulic gradient pit. never let water reach critical level.
upper clark fork river
the upper clark fork river, butte @ headwaters, america s largest superfund site, spanning 100 miles (160 km). area takes in cities of butte, anaconda, , missoula. mining , smelting activity in butte resulted in significant contamination of butte hill downstream , downwind areas. contaminated land extends along corridor of 120 miles (190 km) reaches milltown near missoula , takes in adjacent areas such anaconda smelter site. mining , smelting operations of anaconda copper mining corporation primary cause of pollution @ headwaters of clark fork river.
between upstream city of butte , downstream city of missoula lies deer lodge valley. 1970s, local citizens , agency personnel increasingly concerned on toxic effects of arsenic , heavy metals on environment , human health. of waste created anaconda copper mining corporation (acm), merged atlantic richfield corporation (arco) in 1977. shortly thereafter, in 1983, arco ceased mining , smelting operations in butte-anaconda area.
for more century, anaconda copper mining company mined ore butte , smelted in butte (prior c. 1920) , in nearby anaconda. during time, anaconda smelter released 40 short tons (36 t) per day of arsenic, 1,700 short tons (1,540 t) per day of sulfur, , great quantities of lead , other heavy metals air (macmillan). in butte, mine tailings dumped directly silver bow creek, creating 150 miles (240 km) plume of pollution extending down valley milltown dam on clark fork river upstream of missoula. air , water borne pollution poisoned livestock , agricultural soils throughout deer lodge valley. modern environmental clean-up efforts continue day.
Comments
Post a Comment