In Situ Chemical Oxidation

This study has been conducted at the University of Connecticut (UCONN) in connection with the USEPA Superfund Innovative Technology Evaluation (SITE) program to evaluate a chemical oxidation technology (sodium persulfate) developed at UCONN. A protocol to assess the efficacy of oxidation technologies has been used. This protocol, which consists of obtaining data from a treatability study, tested two in-situ chemical oxidation technologies that can be used on soil and groundwater at a site in Vernon, Connecticut. Based on the treatability report results and additional field data collected at the site, the design for the field implementation of the chemical oxidation remediation was completed. The results indicate that both sodium persulfate and potassium permanganate were able to effectively degrade the target VOCs (i.e., PCE, TCE and cis-DCE) in groundwater and soil-groundwater matrices. In the sodium persulfate tests (120 hrs), the extent of destruction of target VOCs was 74% for PCE, 86% for TCE and 84% for cis-DCE by Na2S2O8 alone and 68% for PCE, 76% for TCE, and 69% for cis-DCE by Fe(II)-catalyzed Na2S2O8. The results demonstrate the sodium persulfate's ability to degrade PCE, TCE and cis-DCE. It is expected that given sufficient dose and treatment time, a higher destruction rate of the dissolved phase contamination can be achieved. The data also indicates that the catalytic effect of the iron chelate on persulfate chemistry was much less pronounced in the soil-groundwater matrix. This indicates an interaction between the iron chelate solution and the soil, which may have resulted in a lower availability of the chelated iron for catalysis. The study showed that the remediation of the VOCs-contaminated soil and groundwater by in-situ chemical oxidation using sodium persulfate is feasible at the Roosevelt Mills site. As a result, the USEPA SITE program will evaluate this technology at this site.

The reaction of the common pain reliever acetaminophen (paracetamol, 4-acetamidophenol) with dichromate was investigated over time under conditions that simulate wastewater disinfection. The occurrence of the acetaminophen in the water bodies, especially in drinking water resources, has received considerable attentions. In situ chemical oxidation is a promising cost-effective treatment method to remove acetaminophen from water body as it degrades the

The Fisherville Mill site is located on the Blackstone River in Grafton, MA. Soil and groundwater are contaminated with chlorinated VOCs and petroleum. The mill and a groundwater recovery system designed to prevent VOCs from migrating to a public water supply well (Well # 3) located approximately 1000 feet southwest of the site were destroyed by fire in August 1999. In November 2000, TCE was detected in Well #3. After notification, site investigation efforts focused on evaluating potential migration pathways to Well #3. Based on site investigation results, the USEPA installed a temporary dam to alter groundwater flow directions and reduce risk to Well # 3. In Situ Chemical Oxidation (ISCO) using sodium permanganate was selected to decrease TCE concentrations in the source area and provide long-term protection for Well # 3. Fisherville Redevelopment Company (FRC) took ownership of the site in 2004. A collaborative approach and strategy was developed between FRC, MassDEP and the Town ...

The reaction of the common pain reliever acetaminophen (paracetamol, 4-acetamidophenol) with dichromate was investigated over time under conditions that simulate wastewater disinfection. The occurrence of the acetaminophen in the water bodies, especially in ...

The MWNT and TiO2 doped Polyaniline (PANI) composites were synthesized by In-situ chemical oxidative polymerization method at low temperature. The MWNT/PANI and TiO2/PANI composite thin films were prepared using spin coating method onto finger type interdigited electrodes to develop the chemiresistor type gas sensor for hydrogen gas sensing application. It was observed that the MWNT and TiO2 doped PANI composite