Gas Sampling Measurements

A model of organic compound removal by biological wastewater treatment processes receiving pulp and paper industry wastewaters has been developed and initial model verification performed at a single mill site. This paper presents the results of further model verification conducted at multiple mill sites, including replication of the original site. In addition, VOC losses at other unit processes are quantified. Activated sludge basin chloroform volatilization rates are predicted to within twelve percent of the measured rates. Predicted overall methanol removals are consistent with observed removals although difficulties encountered during off-gas sampling preclude determination of the extent of removal due to volatilization.

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Development of a direct current gas sampling glow discharge ionization source for the time-of-flight mass spectrometer

Journal of Analytical Atomic Spectrometry ◽

10.1039/a903113h ◽

1999 ◽

Vol 14 (8) ◽

pp. 1121-1127 ◽

Cited By ~ 18

Author(s):

John P. Guzowski, Jr. ◽

Jose A. C. Broekaert ◽

Steven J. Ray ◽

Gary M. Hieftje

Keyword(s):

Glow Discharge ◽

Mass Spectrometer ◽

Direct Current ◽

Time Of Flight ◽

Ionization Source ◽

Gas Sampling ◽

Flight Mass Spectrometer

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Development of a technically defensible soil gas sampling strategy for vapour intrusion assessments

Canadian Geotechnical Journal ◽

10.1139/t08-107 ◽

2009 ◽

Vol 46 (1) ◽

pp. 102-113 ◽

Cited By ~ 5

Author(s):

Tai T. Wong ◽

John G. Agar

Keyword(s):

Human Health Risk ◽

Sampling Strategy ◽

Soil Gas ◽

Assessment Process ◽

Soil Conditions ◽

Gas Monitoring ◽

Gas Sampling ◽

Monitoring Well ◽

Sampling Procedures ◽

Soil Gas Sampling

Soil vapour intrusion is now commonly evaluated as part of human health risk assessments at contaminated sites where buildings or other structures are located in close proximity to volatile organic chemicals (VOCs) in subsurface soils and groundwater. Investigation of the vapour intrusion pathway often requires that VOC concentrations in the soil gas adjacent to buildings and structures be characterized as part of the risk assessment process. This paper presents the design of a new soil gas monitoring well and a sampling procedure that effectively eliminate concerns about soil gas sample dilution due to short-circuiting of atmospheric air and help to ensure the collection of representative soil gas samples. The results of a parametric numerical modelling study that was applied to address the air short-circuiting issue and the technical rationale for the new soil gas monitoring well (SGMW) design are presented in this paper along with recommended soil gas sampling procedures in various soil conditions. The SGMW design rationale and methodology outlined in this paper considered the effects of soil moisture content and permeability, the depth to the sampling screen interval, and the soil gas sample extraction rate.

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