Grantee Research Project Results
1999 Progress Report: Remote Sampling Probe with Fast GC/MS Analysis: Subsurface Detection of Environmental Contaminants
EPA Grant Number: R826184Title: Remote Sampling Probe with Fast GC/MS Analysis: Subsurface Detection of Environmental Contaminants
Investigators: Robbat, Albert , Gorshteyn, Alexander , Smarason, Sigurdur , Katayenko, Zunovi
Current Investigators: Robbat, Albert , Gorshteyn, Alexander , Katayenko, Zunovi , Smarason, Sigurdur
Institution: Tufts University
EPA Project Officer: Aja, Hayley
Project Period: February 16, 1998 through February 15, 2001
Project Period Covered by this Report: February 16, 1998 through February 15, 1999
Project Amount: $305,234
RFA: Exploratory Research - Environmental Chemistry (1997) RFA Text | Recipients Lists
Research Category: Water , Land and Waste Management , Air , Safer Chemicals
Objective:
Reports indicate
that the total amount of money spent on investigating and cleaning the nation's
hazardous waste sites is more than $28 billion. Much of the cost centers on
collecting samples from the site, analyzing them, and then determining the
nature of the contamination and the remedy. Long-term chemical monitoring adds
to final site cleanup costs. Traditional sample collection and analysis programs
rely on collecting subsurface samples and sending them offsite for analysis.
This process is "static." It results in multiple trips to the field until
sufficient information is obtained to answer the scientific and engineering
questions under investigation. In contrast, if samples can be collected and
analyzed in the field quickly enough to impact the decision-making process, the
time and cost of evaluating and cleaning hazardous waste sites should be greatly
reduced. The proposed research is aimed at developing tools that will make this
process more "dynamic" by thermally extracting soil-bound organics and
transporting them to the surface for analysis. The goal is to collect and
analyze volatile and semivolatile organic contaminants (VOCs and SVOCs) onsite,
as near to real-time as possible, by fast gas chromatography/mass spectrometry
(GC/MS).
Progress Summary:
Seventy-foot and 100-foot thermal extraction cone penetrometer (TECP) probes
have been built and tested for electrical, mechanical, and chemical stability.
We have determined the mass balance and TECP thermal extraction efficiency for
nearly all EPA method 8270- and 8260-targeted SVOCs and VOCs. Findings show that
these compounds can be thermally extracted, collected, and analyzed within the
recovery range prescribed by EPA. For soils that contain <20 percent water,
VOCs and SVOCs can be collected in 5 minutes. When the soil-water content is
between 20 percent and 30 percent, 15 minutes are needed to obtain the same
quality data. The latter compares favorably with cone penetrometers or Geoprobes
when used conventionally to bring soil samples to the surface. On the other
hand, sample preparation time prior to analysis is virtually eliminated by the
TECP because it delivers organics in a state ready-made for analysis. In
contrast, soil brought to the surface must be dried, solvent-extracted, and
fractionated by gel permeation before analysis. Also, the TECP collection system
is capable of capturing VOCs and SVOCs separately or simultaneously.
Simultaneous analysis of 8270 and 8260 target compounds saves significant time
over the traditional EPA methods where each compound class is analyzed
separately.
In the last progress report, we described a new ballistically
heated thermal desorption (TD) sample introduction system, where the sample
collected from the TECP probe was introduced directly into the GC. This was a
two-step process. First, the hot vapor was freeze-trapped in a glass tube housed
in the TECP sample collection chamber. Then, the glass tube was brought to the
TD unit, which served as the sample inlet system for the GC. Recently, we
succeeded in tying these two devices together so that the TECP is attached
directly to the GC/MS. This means that we can collect and analyze subsurface
contaminants simultaneously. Although Figure 1 illustrates our first set of
electronic nose experiments, it suggests that the rate of sample collection and
analysis should be at least 10 times faster than the traditional sample
collection and analysis processes. For example, eight consecutive measurements
were made for trinitrotoluene (TNT) and its synthetic precursors in 7 minutes.
Target compounds were desorbed from soil and analyzed in 50 seconds per
analysis. The ultrafast GC was capable of separating closely eluting isomers
(see mononitrated toluenes in Figure 2), while the IFD algorithms were capable
of distinguishing each compound's unique mass spectra. Measurement precision was
20 percent for this experiment. We will continue to develop the TECP-TD GC inlet
for field ruggedness and to determine measurement precision and accuracy for the
wide range of EPA-targeted compounds. An internal/external means of calibrating
the instrument will be developed. Further research will determine the quality of
the data, for example, semiquantitative or quantitative, with the initial
results produced at better than screening quality data. To our knowledge, no
technology exists today that can desorb organics from solids, transport them 70
feet, speciate, and quantify them online.
Future Activities:
The TECP-GC inlet system will be designed, built, and tested for online, simultaneous collection, and analysis of VOCs and SVOCs. We will test the reproducibility of the ultrafast, resistively heated GC, with column temperature programming capabilities approaching 100 0C/second as opposed to conventional GC ovens that program at 30 0C/minute. The GC will operate under ultrafast conditions and be mated to a Hewlett Packard mass spectrometer to provide near to real-time measurements. TECP probe extraction efficiency and collection experiments will be made for the combined system and tested for EPA-targeted pollutants. Research will focus on developing an internal/external calibration system that should lead to the production of quantitative data in the field.Journal Articles on this Report : 6 Displayed | Download in RIS Format
| Other project views: | All 16 publications | 6 publications in selected types | All 6 journal articles |
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Gorshteyn A, Robbat A. Rapid in situ collection and analysis of semivolatile organics by thermal extraction cone penetrometry gas chromatography/mass spectrometry. Field Analytical Chemistry And Technology. 2000;4(2-3):85-92. |
R826184 (1999) |
not available |
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Gorshteyn A, Smarason S, Robbat A Jr. Speciation of subsurface contaminants by cone penetrometry gas chromatography/mass spectrometry. Environmental Science and Technology 1999;33(14):2474-2480. |
R826184 (1999) |
not available |
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Gorshteyn AY, Kataenko Z, Smarason S, Robbat A Jr. Subsurface detection of environmental pollutants. Instrumentation Science and Technology 1999;27(2):111-121. |
R826184 (1999) R826184 (Final) |
not available |
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Robbat A. Environmental applications of thermal extraction cone penetrometry and ultrafast gas chromatography/mass spectrometry. Field Analytical Chemistry and Technology 2001; 5(1-2):60-68. |
R826184 (1999) |
not available |
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Robbat A Jr. Productivity enhancing mass spectral data analysis software for high throughput laboratories: simultaneous detection of volatile and semivolatile organics by GC/MS. Environmental Testing and Analysis 2000;9:15-19. |
R826184 (1999) |
not available |
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Smarason S, Robbat A Jr. Optimizing GC separation methods by employing entropy and enthalpy of solution calculations from temperature-programmed retention data. Journal of Chromatography. |
R826184 (1999) |
not available |
Supplemental Keywords:
soil, in situ analysis, online monitoring, onsite decision making, expedited site characterization, dynamic workplans, green chemistry., RFA, Scientific Discipline, Air, Toxics, Waste, Ecology, Remediation, Environmental Chemistry, Chemistry, HAPS, Hazardous Waste, Hazardous, Engineering, Chemistry, & Physics, Electron Microscopy, thermal extraction, DNAPL, mass spectrometry, subsurface, PCBs, VOCs, Polychlorinated biphenyls (Aroclors), soil screening, gas chromatography, PAH, organic compounds, subsurface detection, analytical chemistry, environmental contaminants, PCB, hazardous chemicals, remote sampling probeRelevant Websites:
http://chem.tufts.edu/faculty/robbat/index.html
http://clu-in.com/char1.html#application
http://www.clu-in.org/video/hanscom.htm
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.