Soil contamination by cadmium (Cd) and lead (Pb) in range and crop lands can occur from polluted sediments carried by the wind. Soils samples were obtained in three different areas on the leeward (east) side of a shallow lake called the Laguna de Bustillos: (1) sediment in the shallow lake (S), (2) soil in the range area adjacent to the shallow lake (RA), and (3) soil in agriculture land (AL) adjacent to the range area. In each area, three composite soil samples were randomly collected at depths of 0-15, 15-30 and 30-50 cm. Therefore, 45 soil samples were analyzed as a 3 (area) x 3 (depth) factorial arrangement. The samples were air dried, passed through a 2.0 mm sieve, ground and passed through a 0.355 mm sieve, and digested with concentrated nitric acid. The metals Cd and Pb were determined using ICP optical emission spectrometry. In addition pH and CE were evaluated. Cadmium concentration was statistically different among areas and showed a strong interaction between depth x area. Maximum Cd concentration was found in S with 0.94 mg kg -1 in the surface horizon (0-15 cm). Lead concentration was different among areas and the interaction was not as strong as the one noted for Cd. Highest Pb concentrations were observed in the surface horizons (0-15 cm) of both S and RA with 74.19 mg kg -1 and 55.09 mg kg -1 . Nevertheless, for the AL system the maximum Pb concentration was found in the subsurface horizon (30-50 cm) with 40.23 mg kg -1 . It is concluded that Cd and Pb are contaminating the RA and AL through wind movement with Pb contamination being the worst.
The hydraulic Conchos Watershed is essential for the inhabitants of the state of Chihuahua, Mexico. Nevertheless, evidence shows that the water that flows in the Conchos River is contaminated. The objective was to determine if Vanadium (V) and Lithium (Li) were present in the water of the Conchos River.
zinc. Standard deviations among groups of samples were generally so high that statistically sound conclusions cannot be drawn. Evidence suggests that ponds at the landfill were high in Ca, Fe, Mg, Mn, and SO. compared to control ponds. A stream adjacent to the site contained greater Mn (207 ug/1) and SO. (229 ppm) than control streams. Shallow alkaline test wells in the landfill had elevated As, Ca, and Se. Acid-neutral test wells had elevated As, Ca, Cr, Mg and Mn. Highest average concentrations of important metals in the groundwater included 83 ug/1 of arsenic and 10 ug/1 of selenium in the alkaline wells; 10 ppm of manganese and 6 ug/1 of chromium in the neutralacid wells. Sulphate averaged 179 8 ppm in the alkaline test wells. The movement of coal ash leachate is thought to be restricted by adsorption and/or exchange of chemical constituents by clay minerals in the vicinity of the landfill. 1 2 Household wells in the vicinity of the landfill showed no evident contamination from the landfill. Average iron concentrations in the biota were tripled, and manganese concentrations doubled in biota affected by the coal ash dump. However, any effects of the disposal area on the dis tribution of the biota could not be separated from effects of varying environment factors such as water movements, substrate composition and food availability. No harmful effects could be demonstrated on the biota in the creek which flowed past the
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