Complex Electrical Resistivity for Monitoring DNAPL Contamination

PDF Version Also Available for Download.

Description

Nearly all Department of Energy (DOE) facilities have landfills and buried waste areas. Of the various contaminants present at these sites, dense non-aqueous phase liquids (DNAPL) are particularly hard to locate and remove. There is an increasing need for external or non-invasive sensing techniques to locate DNAPLs in the subsurface and to track their spread and monitor their breakdown or removal by natural or engineered means. G. Olhoeft and colleagues have published several reports based on laboratory studies using the complex resistivity method which indicate that organic solvents, notably toluene, PCE, and TCE, residing in clay-bearing soils have distinctive electrical ... continued below

Physical Description

vp.

Creation Information

Brown, Stephen R.; Lesmes, David & Fourkas, John September 12, 2003.

Context

This report is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. It has been viewed 26 times . More information about this report can be viewed below.

Who

People and organizations associated with either the creation of this report or its content.

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this report. Follow the links below to find similar items on the Digital Library.

Description

Nearly all Department of Energy (DOE) facilities have landfills and buried waste areas. Of the various contaminants present at these sites, dense non-aqueous phase liquids (DNAPL) are particularly hard to locate and remove. There is an increasing need for external or non-invasive sensing techniques to locate DNAPLs in the subsurface and to track their spread and monitor their breakdown or removal by natural or engineered means. G. Olhoeft and colleagues have published several reports based on laboratory studies using the complex resistivity method which indicate that organic solvents, notably toluene, PCE, and TCE, residing in clay-bearing soils have distinctive electrical signatures. These results have suggested to many researchers the basis of an ideal new measurement technique for geophysical characterization of DNAPL pollution. Encouraged by these results we proposed to bring the field measurement of complex resistivity as a means of pollution characterization from the conceptual stage to practice. We planned to document the detectability of clay-organic solvent interactions with geophysical measurements in the laboratory, develop further understanding of the underlying physical and chemical mechanisms, and then apply these observations to develop field techniques. As with any new research endeavor we note the extreme importance of trying to reproduce the work of previous researchers to ensure that any effects observed are due to the physical phenomena occurring in the specimen and not due to the particular experimental apparatus or method used. To this end, we independently designed and built a laboratory system, including a sample holder, electrodes, electronics, and data analysis software, for the measurement of the complex electrical resistivity properties of soil contaminated with organic solvents. The capabilities and reliability of this technique were documented. Using various standards we performed measurement accuracy, repeatability, and noise immunity tests of this system and we were able to reproduce some key complex resistivity effects quoted in the literature. We attempted numerous times to reproduce the seminal results of Olhoeft and Sadowski on the complex resistivity response of toluene-contaminated clay-rich samples. While we observe similar responses to theirs for plain clays with brine, the addition of toluene does not produce the effects they claimed. We can only produce effects of similar magnitude if we intentionally introduce a large artificial dielectric heterogeneity in the specimen. We have also performed laboratory studies to test the sensitivity of the complex resistivity method to toluene and methanol contamination in sands, clays, and rocks. Additionally, we performed 4-wire IP inversion measurements in a two-dimensional laboratory 'ant farm' to test the ability of this technique to image materials with both conductivity and dielectric heterogeneities. This work indicates, at best, a low sensitivity of the complex electrical resistivity method to organic contamination in rocks and soils. This reduces the short-term prospects of using complex resistivity as an effective technique to directly detect organic contamination. However, as noise suppression techniques improve and further understanding of electrical responses in Earth materials is achieved, the potential of the complex resistivity technique should improve. In contrast, we find that certain electrically polarizing materials, some clays for example, have responses large enough compared to sandy and silty soils to be reliably imaged through a detailed field IP survey. Thus, quantifying soil heterogeneity (which may relate to DNAPL distribution and transport) is an immediate potential application of this technique.

Physical Description

vp.

Notes

OSTI as DE00814942

Source

  • Other Information: PBD: 12 Sep 2003

Language

Item Type

Identifier

Unique identifying numbers for this report in the Digital Library or other systems.

  • Report No.: NONE
  • Grant Number: FG07-99ER15005
  • DOI: 10.2172/814942 | External Link
  • Office of Scientific & Technical Information Report Number: 814942
  • Archival Resource Key: ark:/67531/metadc736705

Collections

This report is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this report?

When

Dates and time periods associated with this report.

Creation Date

  • September 12, 2003

Added to The UNT Digital Library

  • Oct. 18, 2015, 6:40 p.m.

Description Last Updated

  • July 25, 2016, 6:38 p.m.

Usage Statistics

When was this report last used?

Yesterday: 0
Past 30 days: 1
Total Uses: 26

Interact With This Report

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

Citations, Rights, Re-Use

Brown, Stephen R.; Lesmes, David & Fourkas, John. Complex Electrical Resistivity for Monitoring DNAPL Contamination, report, September 12, 2003; United States. (digital.library.unt.edu/ark:/67531/metadc736705/: accessed December 13, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.