History Hydraulic mining

1 history

1.1 precursor: ground sluicing
1.2 california gold rush

1.2.1 environmental consequences
1.2.2 legal consequences


1.3 beyond california

history
precursor: ground sluicing


panoramic view of las médulas

hydraulic mining had precursor in practice of ground sluicing, development of known hushing , in surface streams of water diverted erode gold-bearing gravels. used in roman empire in first centuries ad , bc, , expanded throughout empire wherever alluvial deposits occurred. romans used ground sluicing remove overburden , gold-bearing debris in las médulas of spain, , dolaucothi in britain. method used in elizabethan england , wales (and rarely, scotland) developing lead, tin , copper mines.

water used on large scale roman engineers in first centuries bc , ad when roman empire expanding rapidly in europe. using process later known hushing, romans stored large volume of water in reservoir above area mined; water released. resulting wave of water removed overburden , exposed bedrock. gold veins in bedrock worked using number of techniques, , water power used again remove debris. remains @ las médulas , in surrounding areas show badland scenery on gigantic scale owing hydraulicking of rich alluvial gold deposits. las médulas unesco world heritage site. site shows remains of @ least 7 large aqueducts of 30 miles (48 km) in length feeding large supplies of water site. gold-mining operations described in vivid terms pliny elder in naturalis historia published in first century ad. pliny procurator in hispania terraconensis in 70s ad , must have witnessed himself operations. use of hushing has been confirmed field survey , archaeology @ dolaucothi in south wales, known roman gold mine in britain.

california gold rush

gold miners excavate eroded bluff jets of water @ placer mine in dutch flat, california sometime between 1857 , 1870.

the modern form of hydraulic mining, using jets of water directed under high pressure through hoses , nozzles @ gold-bearing upland paleogravels, first used edward matteson near nevada city, california in 1853 during california gold rush. matteson used canvas hose later replaced crinoline hose 1860s. in california, hydraulic mining brought water higher locations long distances holding ponds several hundred feet above area mined. california hydraulic mining exploited gravel deposits, making form of placer mining.

early placer miners in california discovered more gravel process, more gold find. instead of working pans, sluice boxes, long toms, , rockers, miners collaborated find ways process larger quantities of gravel more rapidly. hydraulic mining became largest-scale, , devastating, form of placer mining. water redirected ever-narrowing channel, through large canvas hose, , out through giant iron nozzle, called monitor . extremely high pressure stream used wash entire hillsides through enormous sluices.

by 1860s, while hydraulic mining @ height, small-scale placer mining had largely exhausted rich surface placers, , mining industry turned hard rock (called quartz mining in california) or hydraulic mining, required larger organizations , more capital. mid-1880s, estimated 11 million ounces of gold (worth approximately us$7.5 billion @ mid-2006 prices) had been recovered hydraulic mining in california gold rush.

environmental consequences

a man leans on wooden sluice. rocks line outside of wood boards create sluice.

while generating millions of dollars in tax revenues state , supporting large population of miners in mountains, hydraulic mining had devastating effect on riparian natural environment , agricultural systems in california. millions of tons of earth , water delivered mountain streams fed rivers flowing sacramento valley. once rivers reached relatively flat valley, water slowed, rivers widened, , sediment deposited in floodplains , river beds causing them rise, shift new channels, , overflow banks, causing major flooding, during spring melt.

cities , towns in sacramento valley experienced increasing number of devastating floods, while rising riverbeds made navigation on rivers increasingly difficult. perhaps no other city experienced boon , bane of gold mining as marysville. situated @ confluence of yuba , feather rivers, marysville final jumping off point miners heading northern foothills seek fortune. steamboats san francisco, carrying miners , supplies, navigated sacramento river, feather river marysville unload passengers , cargo. marysville constructed complex levee system protect city floods , sediment. hydraulic mining exacerbated problem of flooding in marysville , shoaled waters of feather river severely few steamboats navigate sacramento marysville docks. sediment left such efforts reprocessed mining dredges @ yuba goldfields, located near marysville.

the malakoff diggins, california, showing effects of hydraulic mining on hillside on century later. of effects of mining beyond hills themselves, on areas downstream of water , sediment flow produced.

the spectacular eroded landscape left @ site of hydraulic mining can viewed @ malakoff diggins state historic park in nevada county, california. similar landscape can seen @ las médulas in northern spain, roman engineers ground-sluiced rich gold alluvial deposits of river sil. pliny elder mentions in naturalis historia spain had encroached on sea , local lakes result of ground sluicing operations.

legal consequences

vast areas of farmland in sacramento valley buried mining sediment. devastated flood waters, farmers demanded end hydraulic mining. in renowned legal fight of farmers against miners, farmers sued hydraulic mining operations , landmark case of edwards woodruff v. north bloomfield mining , gravel company made way united states district court in san francisco judge lorenzo sawyer decided in favor of farmers , banned hydraulic mining on january 7, 1884, declaring hydraulic mining “a public , private nuisance” , enjoining operation in areas tributary navigable streams , rivers. hydraulic mining on smaller scale recommenced after 1893 when united states congress passed camminetti act allowed such mining if sediment detention structures constructed. led number of operations above sediment catching brush dams , log crib dams. of water-delivery hydraulic mining infrastructure had been destroyed 1891 flood, later stage of mining carried on @ smaller scale in california.

beyond california

the oriental claims near omeo, australia mined between 1850s , 1900s; hydraulic sluicing left man-made cliffs 30 metres (98 ft) high throughout area.

although associated california due adoption , widespread use there, technology exported widely, oregon (jacksonville in 1856), colorado (clear creek, central city , breckenridge in 1860), montana (bannack in 1865), arizona (lynx creek in 1868), idaho (idaho city in 1863), south dakota (deadwood in 1876), alaska, british columbia (canada), , overseas. used extensively in dahlonega, georgia , continues used in developing nations, devastating environmental consequences. devastation caused method of mining caused edwin carter, log cabin naturalist , switch mining collecting wildlife specimens 1875–1900 in breckenridge, colorado, us.

hydraulic mining used during australian gold rushes called hydraulic sluicing. 1 notable location @ oriental claims near omeo in victoria used between 1850s , 1900s, abundant evidence of damage still being visible today.

hydraulic mining used extensively in central otago gold rush took place in 1860s in south island of new zealand, known sluicing.

starting in 1870s, hydraulic mining became mainstay of alluvial tin mining on malay peninsula.

hydraulicking formerly used in polk county, florida mine phosphate rock.