Colorado soils

Figure 3.1. Changes of Zn activity in 10 Colorado soils with pH (data extracted from Ma and Lindsay, 1990)...

Near Mo mine and mill, Colorado SOILS (mg/kg, dry weight)... 

USA Pueblo, Colorado soils from 33 sites 1.8-66.5 Diawara et al. (2006)... 

Arthur, M. A., and T. J. Fahey. 1993b. Controls on soil solution chemistry in a subalpine forest in north-central Colorado. Soil Science Society of America Journal 57 1122-1130. 

Not only have toxic metals been implicated notably in cancer, but crops have been found to absorb these chemicals from the soil. Thus, lettuce absorbs cadmium like a sponge (Wilson, 2001, p. 251). During the controversy, a Colorado soil professor, John Mortvedt, called Mr. Micronutrient, was consulted, who admitted that plants picked up various heavy metal compounds, notably cadmium, especially in acidic soils (Wilson, 2001, p. 172ff). His findings were watered down in subsequent hearings, when he waffled by stating that very little research had been done on heavy metals in micronutrient fertilizers (Wilson, 2001, p. 215) which, Wilson notes, is precisely the point. 

The adsorption of Mo in soils is strongly pH-dependent. Reisenauer et al. (1962) reported that Mo adsorption increased with decreasing pH from 7.75 to 4.45. Possible explanations for that effect on adsorption in that pH range are that hydroxide and MoO/ ions compete for adsorption sites or that Fe and Al oxides become more active as pH decreases (Adriano, 1986). Recently, Mikkonen and Tummavuori (1993b) also found that maximum retention of Mo occurred below pH 4.5 for three Finnish mineral soils. Vlek (1977) studied Mo adsorption on several Colorado soils and developed the following equation to describe the adsorption of Mo as affected by pH ... 

Vlek, P. L. G. (1977). The chemistry, availability and mobility of molybdenum in Colorado soils. Ph.D. dissertation. Department of Plant and Soil Science, Colorado State University, Fort Collins. 

Small tire chips have also been utilized as a soil amendment to improve athletic playing fields (see Recreational surfaces). A patented process marketed under the trade name Rebound (fai Tire) combines cmmb mbber from scrap tires with composted organic material to reduce soil compaction, resulting in better athletic playing surfaces (52). Installations have been made in Florida, California, Colorado, Hawaii, Maryland, Michigan, Missouri, Nevada, Virginia, and Wisconsin. 

Sflf-Test 13.8B Soil at the Rocky Flats Nuclear Processing Facility in Colorado was found to be contaminated with radioactive plutonium-239, which has a half-life of 24 ka (2.4 X 104 years). The soil was loaded into drums for storage. How many years must pass before the radioactivity drops to 20.% of its initial value ... 

J. J. Kilbane, II, P. Chowdiah, K. J. Kayser, B. Misra, K. A. Jackowski, V. J. Srivastava, G. N. Sethu, A. D. Nikolov, and D. T. Wasan. In-situ remediation of contaminated soils using foams as carriers for chemicals, nutrients, and other amendments. In Proceedings Volume. 9th Inst Gas Technol Gas, Oil, Environ Biotechnol Int S)mip (Colorado Springs, CO, 12/9-12/11), 1996. 

Litaor MI. 1995. Spatial analysis of plutonium-239 + 240 and americium-241 in soils around Rocky Flats, Colorado. J Environ Qual 24 506-516. 

Harding Lawson Associates. 1994. Feasibility Study. Soils support program report Rocky Mountain Arsenal, Commerce City, Colorado. Draft Final Version 2. 

The French drain (also called a channel drain or floating slab) is a construction feature that appears to provoke strong reaction from its defenders and detractors alike. French drains are only a concern in basement foundations. This slab detail is a standard feature in new houses in parts of the country as varied as New York and Colorado, but in other places it is virtually unknown. French drains are used in areas with expansive soils, such as parts of Colorado, to protect the slab from damage if the wall moves. In central New York State, the main function of the French drain is to drain away water that may seep down the walls. One national builder has discontinued and now prohibits the use of French drains in houses because of the potential for radon problems. This builder states that French drains also have been found to significantly increase indoor moisture levels. 

In U.S. EPA Office of Radiation Program s New House Evaluation Program (NEWHEP), two builders in the Denver area, two in Colorado Springs, and one in Southfield, Michigan, installed various radon-resistant features in houses during construction. A sampling of subsequent measurements of indoor radon, adjacent soil gas radon, and soil radium content is summarized in Table 31.6.36... 

Indoor Radon and Soil Radon Measurements in Colorado and Michigan... 

The insecticide heptachlor oxidizes in the soil, and becomes a more toxic epoxide, capable of remaining for a long time. The insecticide aldrin transforms in the soil into dieldrin, maintaining its toxicity [15, 30]. Mirex (FDso=300-600 mg/kg), used to fight ants, just like kelevan (FDS0=255-325 mg/kg), used to fight the Colorado beetle, transform in the soil into the more toxic chlordekon (FD50 decreases to 95-140 mg/kg) [30]. 

Casteel WS, Cowart RP, Weis CP, et al. 1997. Bioavailabilty of lead to juvenile swain dosed with soil from the Smuggler Mountain NLP site of Aspen, Colorado. Fund Appl Toxicol 36 177-187. 

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