Microbial Treatment of Naturally Occurring Radioactive Material (NORM)

EPA Grant Number: R827015-01-0
Title: Microbial Treatment of Naturally Occurring Radioactive Material (NORM)
Investigators: Lee R. Krumholz
Institutions: University of Oklahoma
EPA Project Officer: Bala Krishnan
Project Period: July 1, 1999 to June 30, 2000
Project Amount: $9,977
Research Category: NORM remediation

Description:

Objective: The project objectives are do determine the feasibility of using a sulfate reducing microbial consortium from subsurface sediment for the dissolution of NORM containing pipe scale.

Accomplishments: 4-1-00

Geochemical modeling was carried out based on ions present in mineral solutions. Models were generated using PhreeqC, a code generated by the USGS. Figure 1, below shows Ba2+ dissolution as a function of carbohydrates oxidized. In this case the model was generated in

the absence of a witherite (BaCO3) solid phase. The second model (Fig. 2) was run at different starting pH values. A witherite solid phase was added to the model when witherite became saturating. Above pH 7.0 there was little additional effect of pH. This latter model showed us that pH can control reprecipitation of Ba2+ as witherite but not until concentrations reach 0.5 mM at pH 7.0.