Page 7 - Shimadzu Journal vol.3 Issue1

Environmental Analysis

Analysis of Groundwater Quality Using GC-MS, HS-GC-FID, TOC/TN Analysis,

ICP-OES, and a Multi-parameter Probe in a Complementary Fashion

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Jonathan Thacker , Doug D. Carlton Jr.. , Zacariah L. Hildenbrand , Brian E. Fontenot , Kevin A. Schug 1,2
1 Department of Chemistry & Biochemistry, The University of Texas at Arlington, Arlington, TX 76019
2 Affiliate of Collaborative Laboratories for Environmental Analysis and Remediation, The University of Texas at Arlington,
Arlington TX 76019
3 Inform Environmental, LLC (Dallas, TX)
4 Independent Consultant

1. Introduction 3. Metals Analysis with the ICPE-9000

In the United States, the Environmental Protection Agency (EPA) There are a variety of metal ions known or suspected to cause
sets regulations and recommends guidelines for public water health problems that are regulated by the EPA. The Shimadzu
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systems. About 15% of Americans rely on their own private wells ICPE-9000 ICP-OES was used to measure concentrations of various
for their drinking water, but these are not subject to either state metal ions. Samples were acidified to a 2% by volume nitric acid
or federal regulations and are not regularly tested by experts, solution and then filtered as needed. Quantification was
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unlike public water systems. The chemical analysis of groundwa- performed via standard addition to account for varying matrices
ter can be utilized to assess possible contamination as well as among the groundwater samples. High or low cumulative
inform on possible health risks associated with its consumption. concentrations of metal ions determined by ICP-OES could be
The use of multiple instruments to analyze groundwater has the validated by their correlation with conductivity measurements.
advantages of describing groundwater samples more completely 100 groundwater samples from the Barnett Shale of North Texas
than individual measurements, validating measurements, and were analyzed by ICP-OES and the multiparameter probe. Fig. 1
protecting against reporting false positives. To demonstrate this displays the relationship between the sum of estimated concentra-
combinatorial analytical advantage, a Shimadzu QP2010 Ultra gas tions of 64 metal elements determined by ICP-OES and conductiv-
chromatograph- mass spectrometer equipped with a Shimadzu ity for 100 groundwater samples. These data suggest that a
AOC-20i / s autosampler and autoinjector (GC-MS), a Shimadzu relatively high conductivity measurement in groundwater can be a
GC-2010 plus equipped with a flame ionization detector (FID) and general indicator of a high total metals concentration.
a Shimadzu AOC-5000 plus headspace autosampler (HS-GC-FID), a
Shimadzu TOC-L outfitted with a TNM-L total nitrogen module
and a Shimadzu ASI-L autosampler (TOC/TN), a Shimadzu 350
ICPE-9000 inductively coupled plasma- optical emission spectrom- 300 R² = 0.8743
eter equipped with a mini-torch nebulizer, a CETAC ASX-520 250
Autosampler (Teledyne Technologies Incorporated; Omaha, NE,
USA), and argon plasma (ICP-OES), and a YSI Professional Plus &TU .FUBM $POD NH - 200
multiparameter meter (YSI Incorporated; Yellow Springs, OH, USA) 150
were used to characterize groundwater samples. These instru-
ments and associated methods have been applied to analyze 100
approximately 1000 groundwater samples over a 1-year period in 50
regions undergoing unconventional oil and gas (UOG) production
in the USA. 0
0.0 1.0 2.0 3.0 4.0 5.0 6.0
$POEVDUJWJUZ N4 DN
2. General Groundwater Quality Parameters
At each sampling site, groundwater was purged for approximately Fig. 1 Total concentration of metal elements determined by
20 – 30 minutes (until temperature, oxidation/reduction potential, ICP-OES and its correlation with measured bulk
and pH values had stabilized) from a water well before collection. conductivity in 100 groundwater samples.
The YSI multiparameter probe was used to measure general
groundwater quality parameters, including temperature, pH,
conductivity, dissolved oxygen, oxidation/reduction potential, and
turbidity. These data may be used to support measurements from
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more detailed analytical techniques.

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