Homestake

CIP (1) [Carbon In Pulp] A general name for hydrometallurgical extraction processes that use activated carbon in slurries of ground ores. One such process is used for extracting gold from cyanide leach liquors. First operated on a large scale at the Homestake lead mine in South Dakota in 1974. See also RIP. 

Five experiments have so far detected solar neutrinos. These are Homestake (USA), GALLEX, SAGE, KAMIOKANDE and SUPERKAMIOKANDE, all set up down mines or tunnels. Detected fluxes agree qualitatively with theoretical predictions, both in numbers and energies. We may say that we have basically understood how the Sun shines. The same set of nuclear reactions invoked to explain the solar luminosity does give rise to neutrinos. 

At the Homestake Mine in Lead, South Dakota, 48 RBCs were installed to treat 5.5 million gallons of discharge water per day. The system degraded thiocyanate, free cyanide, and metal-complexed cyanides, and also removed ammonia, which is a by-product of cyanide degradation. Over time, as the system became more efficient, the cost to treat cyanide dropped from 11.79 to 3.10/kg (D15372K, p. 6). 

An early detector was established in the shaft of the Homestake Mine (South Dakota) in 1968. The data gathered did not correspond with the scientists expectation. The neutron flux measured was less than one-third that predicted. This discrepancy challenged researchers to question perhaps the established concepts of particle physics and indeed the manner in wlucli the suu functions. 

The solar neutrino problem was identified by the first results of Davis et al. using the Cl detector at the Homestake Mine. Davis et al. observed only about one-third of the expected solar neutrino flux as predicted by standard models of the sun, which assume 98.5% of the energy is from the pp chain and 1.5% of the energy is from the CNO cycle. The final result of the Cl detector experiment is that the observed solar neutrino flux is 2.1 + 0.3 SNU compared to the predicted 7.9 + 2.4 SNU, where the solar neutrino unit (SNU) is defined as 10-36 neutrino captures/second/target atom. The GALLEX and SAGE detectors subsequently reported solar neutrino fluxes of 77+10 SNU and 69+13 SNU, which are to be compared to the standard solar model prediction of 127 SNU for the neutrinos detected by these reactions. 

Rye D. M. and Rye R. O. (1974) Homestake gold mine. South Dakota I. Stable isotope studies. Econ. Geol. 69, 293—317. 

FIGURE 9,2-3 Carbon-in-pulp process For recovery or gold at Homestake Mining Company. (Reproduced from McQuislon and Shoemaker,")... 

Homestake to water-soluble NaVOa, leached from Na2U207 ... 

Figure 5.4 Schematic flow sheet, United Nuclear-Homestake Partners uranium mill.

Source Homestake mine, Ambrosia Lakes, McKinley County, New Mexico, U.S.A. ... 

Christiansen JA, Hevesy G, Lomholt S (1924) Recherches, par une m hode radiochimique, sur la circulation du bismuth dans Torganisme. Compt Rend 178 1324 Cleveland BT, Daily T, Davis R Jr et al (1998) Measurement of the solar electron neutrino flux with the Homestake chlorine detector. Astrophys 1496 505... 

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