7th International Conference on Remediation of Con

7th International Conference on Remediation of Contaminated Sediments.

MSE-TA Presentation Abstract (Search with "Bickford" will go directly to it)
http://conferences.battelle.org/sediments/pdf...ection.pdf

Strategies for Treating and Dewatering Contaminated Soils and Sediments Simultaneously
Jody Bickford (jody.bickford@mse-ta.com) and Martin Foote
(MSE Technology Applications, Inc., Butte, Montana, USA)

Background/Objectives. Heavy metal contamination poses remediation challenges in soils and sediments throughout the world. This abstract describes the bench-scale testing performed for two proven technologies that were combined to determine if a metals treatment agent could be combined with a superabsorbent polymer to simultaneously treat and dewater soils and or sediments. Across the United States there are many contaminated river and stream sediments and soils that may benefit from this combination of treatment. Approach/Activities. The initial testing consisted of spiking soil samples with four heavy metals: lead, mercury, cadmium, and chromium to generate the simulated contaminated soil for testing. Water was added to the simulated soil at 30 and 40 weight percent. Toxicity Leaching Characteristic Procedure (TCLP) data was collected for the clean and spiked soils before treatability testing was initiated. TCLP data was also collected after the different treatment addition methods were employed to determine reagent efficacy.

Molecular Bonding System™ (MBS) was the metals treatment agent used and Waste Lock 770® (Waste Lock) was the superabsorbent polymer used during the testing. The go/no-go testing consisted of adding either Waste Lock or MBS to the spiked soil to determine the affects for each of the additions separately. Paint Filter Tests (PFT) and TCLP data were collected on the samples treated with Waste Lock and MBS.

The go/no-go testing that was performed at the MSE test facility consisted of adding both treatment agents to the surrogate soil using three different addition methods. The first addition method specified that MBS was mixed into the simulant soil and then the Waste Lock was added and mixed. The second addition method specified that Waste Lock was mixed into the soil matrix and then MBS was added to the soil with mixing and the third addition method specified that both treatment agents be added to the soil simultaneously with mixing. Soil samples were collected for TCLP analysis within minutes of the reagent additions, and submitted to the MSE Analytical Laboratory.

Results/Lessons Learned. The small scale go/no-go testing proved that MBS and Waste Lock can be added simultaneously to dewater and treat metals contamination to TCLP levels below regulatory standards for the simulated soil samples. Follow-on treatability testing will consist of testing soils spiked with mercury, cadmium, chromium, lead, nickel, and zinc because these metals were routinely used in industry and represent current treatment needs. The testing will be performed later this year using MBS and Waste Lock to obtain repeatable results.