Accession Number:

ADA512826

Title:

Remediation of DNAPL through Sequential In Situ Chemical Oxidation and Bioaugmentation

Descriptive Note:

Final rept.

Corporate Author:

GEOSYNTEC CONSULTANTS ATLANTA GA

Personal Author(s):

Report Date:

2009-04-01

Pagination or Media Count:

93.0

Abstract:

The principal benefit of in situ chemical oxidation ISCO using permanganate MnO4is that it aggressively enhances dissolution and destruction of the target contaminants within a relatively short period of time i.e., months to years however, the cost-benefit of this technology diminishes as the mass of target chemicals decreases. The most effective application of ISCO consists of rapid destruction of the readily accessible target chemical mass within the source area, although it can also be coupled with a less costly, in situ remediation mass removal technology such as in situ bioremediation ISB. The main objectives of this project was to assess the technical feasibility of sequential application of these technologies and to identify the optimal timing of the transition from ISCO to ISB. The principal results of the project include 1. Electron donor addition ISB after ISCO resulted in partial biodegradation of trichloroethene TCE, with complete biodegradation observed after bioaugmentation 2. At the field-scale, ISB did not increase the mass flux of chloroethenes after ISCO 3. The precipitated manganese dioxide produced by MnO4 - reduction, which can oxidize some organic compounds, did not abiotically degrade any of the chloroethenes or ethene 4. Manganese dioxide MnO2 greatly increases the electron donor demand above that typically required to reduced the dissolved constituents e.g., oxygen, nitrate, sulfate, and the target chloroethenes during ISB 5. MnO2 can be dissolved by the activity of MnIV- reducing bacteria, that appear to preferentially utilize hydrogen and inhibit the activity of dechlorinating microorganisms i.e., Dehalococcoides, which use hydrogen as their sole electron donor and 6.The limited cost assessment indicated that there was a significant cost and schedule advantage for the sequential treatment strategy over using pump and treat or ISCO alone.

Subject Categories:

  • Organic Chemistry
  • Solid Wastes and Pollution and Control
  • Water Pollution and Control
  • Ecology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE