Iron Mountain

Ml It means that the activity of H (discussed in Chapter 8) is I036. D. ft Nordstrom. C. N. Alpers, C. J. Ptacek, and D. W. Blowes. Negative pH and Extremely Acidic Mine Waters from Iron Mountain, California, Environ. Sci. Technoi. 2000, 34.254.]... 

Acidic mine water. Iron Mountain, Calif. 

D. W. Blowes, Negative pH and Extremely Acidic Mine Waters from Iron Mountain. California. Environ. Sci. Technol. 2000, 34, 254. 

A variety of bacteria and other microorganisms, such as the archaeum Ferriplasma acidarmanus, may be actively involved in the oxidation of arsenopyrite (Gihring et al., 1999 Cruz et al., 2005 Barrett et al., 1993). Specifically, (Gihring et al., 1999) collected Thiobacillus caldus and Ferriplasma acidarmanus from acid mine drainage at Iron Mountain, California, USA. The mine drainage had a temperature of approximately 42 °C, a pH of 0.7, and contained about 50 mg L 1 of arsenic. T. caldus growths on the surfaces of arsenopyrite actually hindered the oxidation of the mineral, whereas F. acidarmanus was very tolerant of arsenic and accelerated the dissolution of arsenopyrite (Gihring et al., 1999). 

Nordstrom, D.K. and Alpers, C.N. (1999) Negative pH, efflorescent mineralogy, and consequences for environmental restoration at the Iron Mountain Superfund site, California. Proceedings of the National Academy of Sciences of the United States of America, 96(7), 3455-62. 

Nordstrom DK, Alpers CN, Placek CJ, Blowes DW (2000) Negative pH and extremely acidic mine waters from Iron Mountain, California. Environ Sci Technol 34 254-258... 

Robbins El, Rodgers TM, Alpers CN, Nordstrom DK (2000) Ecogeochem-istry of the subsurface food web at pH 0-2.5 in Iron Mountain, California, U.S.A. Hydrobiologia 433 15-23... 

Underground in the Richmond Mine at Iron Mountain, California, extremely acidic mine waters have been encountered, with pH ranging from 1.5 to —3.6 and total dissolved metal (mainly iron) and sulfate concentrations as high as 200 g and 760 g respectively. These are the most acidic waters known. 

Figure 2. Location of Spring Creek and its two tributaries, Boulder and Slick-rock Creeks, which contain acid mine drainage and drain the Iron Mountain...

A suite of both oxidized and reduced iron minerals has been found as efflorescences and precipitates in or near the acid mine water of Iron Mountain. The dominant minerals tend to be melan-terite (or one of its dehydration products), copiapite, jarosite and iron hydroxide. These minerals and their chemical formulae are listed in Table III from the most ferrous-rich at the top to the most ferric-rich at the bottom. These minerals were collected in air-tight containers and identified by X-ray diffractometry. It was also possible to check the mineral saturation indices (log Q(AP/K), where AP = activity product and K = solubility product constant)of the mine waters with the field occurrences of the same minerals. By continual checking of the saturation index (S.I.) with actual mineralogic occurrences, inaccuracies in chemical models such as WATEQ2 can be discovered, evaluated and corrected (19), provided that these occurrences can be assumed to be an approach towards equilibrium. 

Alpers C. N., Nordstrom D. K., and Burchard J. M. (1992) Compilation and Interpretation of Water Quality and Discharge Data for Acid Mine Waters at Iron Mountain, Shasta County, California, 1940—91. US Geol. Surv. Water-Resour. Invest. Report 91-4160, 173pp. 

Recent studies at the Iron Mountain acid mine-drainage site in California suggest that the main role of A. ferrooxidans is to oxidize iron downstream from the principal acid-generating site, and that the primary effect is to enhance the precipitation of iron oxyhydroxides (Banfield and Welch, 2000). Other iron-oxidizing bacteria (e.g., L. ferrooxidans) and archeal (e.g., Thermoplasmales) species have been observed proximal to the sulfide ore (Edwards et al., 2000). The utilization of energy derived from iron or sulfur oxidation in other prokaryotes remains unclear, but it can be surmised that the mechanism involved could be broadly similar to that determined for A. ferrooxidans (Banfield and Welch, 2000). 

A notable locality for acid drainage is Iron Mountain, California, where oxidation of pyritiferous massive sulfide deposits has resulted in the formation of many of the aforementioned soluble salts in the underground workings. The precipitation order of the salts at Iron Mountain follows the divalent to trivalent trend (Nordstrom and Alpers, 1999b). 

Edwards K. J., Gihring T. M., and Banfield J. F. (1999) Geomicrobiology of pyrite (FeS2) dissolution a case study at Iron Mountain, California. Geomicrobiol. J. 16, 155-179. 

Iron Mountain Farmers Market Behind City Hall Iron Mountain, MI b 906-779-9034 Seasonal... 

Alpers, C. N., D. K. Nordstrom, and J. W. Ball. 1989. Solubility of jarosite solid solutions precipitated from acid mine waters, Iron Mountain, California, U.S.A. Sci. Geol. Bull. (Strasbourg)42 2S -9S. 

Thiobacillus thiooxidans also accelerate the process. Low-pH waters from tailings and acid mine waters have been reported in the range of 0.1-2.1 (Alpers et al., 1992), with the lowest value being reported as — 3.6 at the Richmond Mine at Iron Mountain, California, which is now a Superfund site (Nordstrom et al., 2000). Dissolved metal concentrations as high as 200 g/L have also been recorded in this AMD. 

Copper Richmond Mines, Iron Mountain, USA Britannia Mines, Canada Nordstrom et al. (2000) Grout and Levings (2001)... 

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