An Assessment of Conventional in Situ Air Sparging Pilot Tests

Paul C. Johnson, Richard L. Johnson, Christopher Neaville, Erik E. Hansen, Steve M. Stearns, Ira J. Dortch

Research output: Contribution to journalArticlepeer-review

24 Scopus citations

Abstract

Short-term (< 24 h) pilot tests play a key role in the selection and design of in situ air sparging systems. During air injection, changes in dissolved oxygen in ground water, water levels in wells, soil gas pressures, and soil gas contaminant concentrations are measured. These parameters are assumed to be indicators of air sparging feasibility and performance. In this work we assess the validity of this critical assumption. Data are presented from a study site where a typical short-term test was conducted for three days, followed by continued operation of a full-scale system for 110 days. Conventional sampling practices were augmented with more discrete and detailed assessment methods. In addition, a tracer gas was used to better investigate air distributions, vapor flow paths, and vapor recovery efficiency. The data illustrate that conclusions regarding the performance and applicability of air sparging can vary dramatically depending on the monitoring approach used. Samples collected for chemical analyses from conventional monitoring wells were clearly affected by the air sparging during, and for some time after, air injection. Results from this site suggest that typical pilot test measurements might be useful for assessing infeasibility, but do not yield sufficient information to extrapolate to long-term performance.

Original languageEnglish (US)
Pages (from-to)765-774
Number of pages10
JournalGround Water
Volume35
Issue number5
DOIs
StatePublished - Jan 1 1997

ASJC Scopus subject areas

  • Water Science and Technology
  • Computers in Earth Sciences

Fingerprint Dive into the research topics of 'An Assessment of Conventional in Situ Air Sparging Pilot Tests'. Together they form a unique fingerprint.

Cite this