1995-08-11_REVISION - M1977493 (10)

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01/11/1995 08:36 2168648136 MVTECHNOLOGIES, INC. PAGE 07 2-3 Each of the waste rock samples was tested for the presence of Thiobacillus ferrooxidans. A 500g subsample of each sample was saturated with distilled and deionized (W) water. The subsample was shaken for 24 hours. A 0.5ml aliquot of solution representing a specific material was added to the first of the six cells - all containing 0.9ml of a ferrous-iron rich media (9K). After the first cell was inoculated and mixed, O.lml of cell one was transferred to cell two and mixed. This process was repeated until all six cells were inoculated. Positive results ird.i,cating the presence of T. ferrooxidans are noted by a distinct color change in the 9K media (clear yellow to a cloudy reddish brown) . Sulfur forms and an acid-base account were done for all ten samples taken at the sites. All analyses were done according to applicable methods for disturbed overburden materials and coal refuse. The methods found in U. S. EPA publication 670/2-78-054, "Field and Laboratory Methods Applicable to Overburdens and Mine Soils," were used in original or upgraded forms. The lime requirements method is found in, Soil Fertility Information Series No. 3, published by the Cooperative Extension Service of the West Virginia University Center for Extension and Continuing Education. Both of the water samples were analyzed for pH, specific conductivity, acidity, sulfates, iron, manganese and aluminum. Discussion The water quality data (Table 3) show the impact of the said-generating waste rock on ground and/or surface water contacting it. Sample 98049-A was taken from a perched water table groundwater spring emerging from natural ground on the northeast side of the McNulty dump. The water is of good quality with virtually no sulfates or metals, no acidity, and a pH of 7.1. Sample 88049-B was taken at the base of the McNulty dump from seepage infiltrating down through the waste rock. The pH has fallen to 3.1. acidity has risen to 2182mg/L, and the sulfate concentration (an excellent indicator of stored acid) is 3125mg/L. Iron, manganese and aluminum concentrations were virtually undetectable in sample 88049-A but now have risen to unacceptable levels. The most disturbing figure is the concentration of aluminum (330mg/L) . Aluminum is toxic at low concentrations to many types of plants. The acid-base account data (Table 4) show the majority of the rock dump to be fairly homogeneous except for samples 88049-1, 88049-2, and 88049-6. These three samples differ because they do have excess neutralizers available; however, samples 88049-1 and 88049-2 still have slightly acidic paste pH values. Sample 88049-1 is more highly weathered than 88049-2, thus having the lower paste pH. Sample 88049-5 has a slightly alkaline paste pH despite having a much larger pyrite content than 88049-1 and 89049-2. The reason is two-fold: first, the rock (a shale) has a higher concentration of neutralizers; second, a portion of the neutralizers is carbonates, which are