Efficacy of an In‐Well Sonde to Determine Magnetic Susceptibility of Aquifer Sediment

Abstract

Magnetite is a natural component of many aquifers. Abiotic degradation of chlorinated solvents by magnetite can be an important mechanism for natural attenuation of these contaminants. The quantity of magnetite in aquifer materials can be estimated by measuring the magnetic susceptibility of the materials. This is most commonly done by determining the magnetic susceptibility of core samples in an analytical laboratory using a magnetic susceptibility meter. Unfortunately, the cost of acquiring core samples often makes an evaluation of abiotic degradation by magnetite economically unrealistic. Downhole sondes (probes) are available for the determination of magnetic susceptibility. In this study, a downhole sonde was evaluated as an affordable alternative to acquiring and analyzing core samples. The sonde was introduced into 10 monitoring wells. The data from the sonde were then compared to data from core samples that were collected from the same elevation as the sonde data. The core samples analyzed in the laboratory were used as the standard against which the sonde data were compared. The downhole sonde reported values that were similar to values reported on core samples. At most wells, the means of the two measurements could not be distinguished at the 95% confidence interval. When the means could be distinguished, they still agreed within a factor of two.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 12, 2017
Source ID
10.1111/gwmr.12197

Entities

People

  • Barbara H. Wilson
  • John T Wilson
  • Mark L. Ferrey
  • Todd H. Wiedemeier

Organizations

  • Environmental Security Technology Certification Program

Tags

Fields of Study

  • Environmental science

Readers

  • Analytical Chemistry
  • Atmospheric Science/Meteorology
  • Geotechnical Engineering.