Jody L. Hudson

Procedures used to measure the amount of 2,3,7,8-tetrachlorodibenzo-p-dioxin in the ambient air near a superfund site cleanup operation

Sampling procedures and analytical procedures are described that were successfully used to monitor for 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) in air samples collected near a Superfund site cleanup operation. Measured concentrations of 2,3,7,8-TCDD in air samples are related both to an action level (3.0 pg per standard cubic meter of air) and to a calculated no observed effect level (5.5 pg/mT). The study concluded that it is possible to collect reliable data for 2,3,7,8-TCDD in air at concentrations that are below the action level specified by the Centers for Disease Control. Data quality was defined relative to the quality control procedures described in the study. There was no apparent relationship between particulate matter in the air and 2,3,7,8-TCDD in the air.

A Method of Predicting Point and Path- Averaged Ambient Air VOC Concentrations, Using Meteorological Data

A method of predicting point and path-averaged ambient air VOC concentrations is described. This method was developed for the case of a plume generated from a single point source, and is based on the relationship between wind directional frequency and concentration. One-minute means of wind direction and wind speed were used as inputs to a Gaussian dispersion model to develop this relationship. Both FTIR spectrometry and a whole-air sampling method were used to monitor VOC plumes during simulated field tests. One test set was also conducted using only whole-air samplers deployed in a closely-spaced network, thus providing an evaluation of the prediction technique free of any bias that might exist between the two analytical methods. Correlations between observed point concentrations and wind directional frequencies were significant at the 0.05 level in most cases. Predicted path-integrated concentrations, based on observed point concentrations and meteorological data, were strongly correlated with observed...

Evaluation of method performance for measuring 2,3,7,8-tetrachlorodibenzo-p-dioxin in ambient air

Abstract High volume sampling in combination with GC/MS analytical techniques have been used to measure 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) in ambient air at numerous sites within Region VII, U.S. EPA. Extensive use of these procedures have resulted in a large database of information which has been used to evaluate and document the methods performance.

Evaluation of emissions from remedial activity at a former manufactured gas plant by open-path Fourier transform infrared spectroscopy

Open-path Fourier Transform Infrared Spectroscopy (OP-FTIR) was used to conduct an air monitoring survey at a Fourier manufactured gas plant (FMGP) superfund site. This survey was performed in support and at the request of the Waste Management Division, U.S. EPA, Region VII. A three day study was conducted in which the OP- FTIR instrument was operated at several fenceline locations around the perimeter of the site in order to detect and quantify benzene emissions. Results of the survey indicated that benzene emissions correlate very closely with site excavation and soil processing activities. Varying concentrations of benzene were detected were and quantified in the field in near-real time. Laboratory analysis of the field data also indicated concentrations of ammonia and toluene at levels above the instrumental detection limit.

Optimization of a Fourier transform infrared spectrometer during on-site pollution analysis

The field transportable Fourier transform infrared (FT-IR) spectrometer system developed at Kansas State University is now finishing the testing stage. The testing stage consisted of three parts: the measurements of (1) controlled releases of volatile organic compounds (VOC), (2) uncontrolled VOC releases at well documented sites, and (3) uncontrolled VOC releases at complex sites with little or no precharacterization1. Some measurements have been acquired in all three categories with most of the data acquisition taking place in the first two categories, which are discussed in these proceedings. These tests were developed to validate the qualitative and quantitative capabilities while enhancing the versatility and detection limits of the spectrometer system. The controlled VOC releases, for the most part, took place at the University of Kansas (KU). The KU tests utilized a co-monitoring technique, evacuated stainless steel canisters followed by GC/FID analysis, during the acquisition of the infrared data. The ability to monitor the concentrations of the released plume with another technique allowed for the comparison and examination of how varying parameters can affect the infrared spectrometer technique. The varying parameters that were addressed were wind, path length, temperature, barometric pressure, water and carbon dioxide concentration, and air borne particulates. One set of uncontrolled releases occurred at an active production facility. A list of the possible compounds that might be observed from the facility directly due to production was obtained. Infrared measurements were acquired at two different setup geometries down wind and one setup geometry up wind. The three path lengths were 390 meters, 500 meters, and 412 meters respectively. During these measurements two series of canister samples were obtained down wind and one series of canister samples were obtained up wind. The analyses of these canisters, on-going at this writing, is being performed by GC/FT-IR (matrix isolation). When the analysis from this method is complete the results will be compared. These two different data acquisitions have led to much insight into the capabilities of the spectrometer system and how varying parameters can affect the FT-IR spectrometers performance. Preliminary analysis of the spectroscopic data from both data acquisitions will be discussed.

Estimation of VOC emission rates from FTIR measurements and whole-air canister data

Methods of estimating VOC emission rates from a point source are being field tested by the University of Kansas, in cooperation with Region VII of the U.S. EPA and Kansas State University. The methods use path-integrated VOC concentrations, meteorological data, and a form of the Gaussian dispersion equation. VOC concentrations were derived both from a whole-air canister sampling method, with subsequent GC analysis, and from open-path FTIR measurements; estimated emission rates produced from the two analytical methods were compared. Canister-derived concentrations provided higher mean estimation accuracies than did FTIR measurements for both 1, 1, 1-Trichloroethane and toluene; however, for a third data set consisting of all other compounds released, FTIR measurements provided higher values. Estimation accuracy also was evaluated as a function of atmospheric stability and downwind distance; accuracy generally increased and variability decreased as stability increased; accuracy was better at longer than at 50 meters.

Assessment of data intercomparability and data quality for multiple open-path FTIR systems

There exists little information concerning the quality of data generated from open-path Fourier transform infrared spectrometer (OP-FTIR) systems as applied to measuring toxic air pollutants. The U.S. Environmental Protection Agency, Region VII conducted a study designed to assess the intercomparability and data quality for several OP-FTIR systems. This paper describes the design of the study, presents the resulting data, and discusses the conclusions reached.

Art of atmospheric monitoring

Road, Kansas City, Kansas 66115D.F. GurkaU.S. Environmental Protection Agency, Quality Assurance DivisionEnvironmental Monitoring Systems Laboratory, Las Vegas, Nevada 89119ABSTRACTThe Department of Chemistry at Kansas State University has been developing and testing a mobileFourier transform infrared (FT-IR) spectrometer system. The main purpose of the mobile FT-IR spectrometersystem is for performing long-path atmospheric monitoring of volatile organic compounds (VOCs) from avariety of emission sources.15Testing of the FT-IR system began four years ago with controlled release of VOCS at the Universityof Kansas (stage 1). The testing has culminated with monitoring of sites where uncontrolled releases of VOCSare occurring and the site itself has little or no precharacterization (stage 3).1

Fourier transform spectroscopy: from organizing MISFITS to FTing it in a truck

Open-cell long-path Fourier transform infrared (FT-IR) spectroscopy has become a common technique for the monitoring of fugitive emission of VOCs in the atmosphere. Our entry into the study of VOCs in the atmosphere is presented in a historical context. The evolution of our techniques for carrying out field studies is described. Some representative examples of our monitoring activities are given and referenced. Some more recent concerns are presented and future directions are indicated.

Testing and development of a mobile Fourier transform infrared spectrometer system for the analysis of atmospheric pollutants

The mobile Fourier transform infrared (FT-IR) spectrometer system for the monitoring of volatile organic compounds (VOCs) is now entering its third and final stage of testing. At present, data have been collected in all three stages of testing. From the results obtained during the three stages of testing, modifications have been made to the mobile FT-IR spectrometer system to increase its overall performance in the field.