Volatile Organic Compounds In Soil Research Articles

Comparison of analytical methods for determination of volatile organic compounds in soils

This study compares aqueous extraction headspace/gas chromatography and purge-and-trap gas chromatography/mass spectrometry (EPA SW-846, method 8240) for the determination of four volatile organic compounds (VOCs) in soil. Comparisons were performed on two fortified soils and two soils obtained from sites where hazardous waste had been spilled or disposed. In only two of the cases studied were significant differences consistently found; for the two most hydrophobic compounds in a high organic carbon soil and for TCE in a field-contaminated soil that had previously shown slow aqueous VOC desorption. The findings strongly suggest that aqueous extraction/headspace GC using a portable instrument can be used to screen soils on site for VOCs, providing rapid same-day results, that will consistently identify the presence of these analytes and provide quantitative results which are generally not significantly different from slower more expensive, laboratory-based purge-and-trap analysis. 29 refs., 3 figs., 7 tabs.

Volatile organic compounds in contaminated soils: The nature and validity of the measurement process

A wide variety of volatile organic compounds (VOCs) such as toluene and trichloroethene routinely appear as principal pollutants in contaminated sites. As part of the site assessment and environmental restoration process, quantitative determination of soil VOCs is required. While accurate and precise measurements are desired, the validity of the current process in which a discrete sample is collected and a 1 to 5 g subsample is analyzed for a suite of organic compounds of widely different properties is questionable. Research has demonstrated that the soil VOC measure- ment process is complex and current, commonly employed practices can lead to substantial measurement errors. For example, −100 to +25% bias can occur in measurements of some soil VOCs. Knowledge of VOC behavior in soils and the measurement process continues to expand and advances are being made in sampling and analysis techniques. Further research is needed to enable development of a valid soil VOC measurement process.

Trace determination of volatile organic compounds in soil based on thermal vaporization followed by Tenax-GC trapping and capillary gas chromatography—mass spectrometry

A simple method for the determination of trace volatile organic compounds in the soil was developed, based on the thermal vaporization of the volatile organics from the sample (1–3 g) and their entrapment on Tenax-GC adsorbent, followed by capillary gas chromatography—mass spectrometry. Using this method, volatilehydrocarbons, aldehydes, sulphides and ketones could be measured in garden soil.

Innovative technologies for hazardous waste treatment

The Superfund Amendments and Reauthorization Act (SARA) has mandated the evaluation of innovative technologies to the end of accomplishing permanent nonland disposal-based remedial cleanup of uncontrolled hazardous waste sites. Four such innovative technologies that have been evaluated and subsequently implemented at multiple sites include: 1. In situ air stripping of volatile organic compounds (VOCs) in soils 2. Low temperature thermal stripping of VOCs in soils. 3. Incineration of explosives and polychlorinated biphenyl (PCB) compounds in soils. 4. Biodegradation of hazardous organic compounds.[ ] A description of each technology is presented in this paper. An overview of previous studies and treatment costs associated with each technology are also included.