The Use of Portable Instrumentation for Assessing Environmental Contamination in the Urals Region of Russia

Abstract

Two of the principal environmental contamination problems facing the mining regions of the Urals are pollution of air and water by volatile organic chemicals and pollution of air, water and soil by heavy metal wastes from mining and heavy industry such as steel production. Because of the extent of these problems and the large areas affected in the Urals region the use of on-site analysis instruments would provide a powerful tool for making rapid assessments of air, water and soil contamination and for determining where to sample when samples are to be returned to a central laboratory for confirmatory analysis or for further intensive testing. The first instrument is a very sensitive gas chromatograph using photoionization as the detection principle. This instrument has been widely used in America to perform rapid assessment of air, water and soil contamination from gasoline and other fuel leaks, hazardous waste disposal sites and workplace monitoring to protect workers from unnecessary exposure to volatile chemicals. The instrument has sensitivity to aromatic compounds and ethylene type compounds such as trichioroethylene (TCE) and vinyl chloride (VCM) down to the pictogram range. This results in a sensitivity to benzene and TCE of about 1-10 ppb in air. Water and soil are analyzed using the simple technique of analyzing headspace in a closed vial for water or by placing soil in a vial with appropriate amounts of methanol or water and analyzing the headspace above the aqueous slurry or by dilution of the methanol extract in water and again using headspace analysis. Using the simple principle of Henry's Law, water can be analyzed for volatile organic down to the ppt range for aromatics and the low ppb range for alkanes (e.g. carbon tetrachloride, etc). Detection of volatile contamination from spills or leaks of volatile organic chemicals can be done using another simple field technique. The technique is called ``Soil Gas Analysis{''} and consists of making a small borehole in the area of a suspected contamination incident and sampling the soil gas, using the field gas chromatograph to produce real time data on the nature, spread and concentration of the spilled material in the soil. This technique has found very widespread use in America where many buried fuel tanks have been found leaking with the consequent problem of widespread contamination of ground water supplies. The second instrument is a portable X-Ray Fluorescent (XRF) Analyzer. This instrument uses a low level radioactive source (Cd 109) to excite heavy metal atoms in a sample which then fluoresce to produce characteristic (Raleigh) scattered peaks which can be used for both qualitative and quantitative analysis. With this instrument, the presence of lead and other toxic heavy metals can be readily detected in the field to determine where soil has been contaminated by mining and metallurgical operations, leaving the soil at levels that are dangerous especially to children playing in and around these operations.