ISCO for Groundwater Remediation: Analysis of Field Applications and Performance

Abstract

A critical analysis of in situ chemical oxidation (ISCO) projects was performed to characterize situations in which ISCO is being implemented, how design and operating parameters are typically employed, and to determine the performance results being achieved. This research involved design of a database, acquisition and review of ISCO project information, population of the database, and analyses of the database using statistical methods. Based on 242 ISCO projects included in the database, ISCO has been used to treat a variety of contaminants; however, chlorinated solvents are by far the most common. ISCO has been implemented at sites with varied subsurface conditions with vertical injection wells and direct push probes being the most common delivery methods. ISCO has met and maintained concentrations below maximum contaminant levels (MCLs), although not at any sites where dense nonaqueous phase liquids (DNAPL) were presumed to be present. Alternative cleanup levels and mass reduction goals have also been attempted, and these less stringent goals are met with greater frequency than MCLs. The use of pilot testing is beneficial in heterogeneous geologic media, but not so in homogeneous media. ISCO projects cost $220,000 on average, and cost on average $94/yd 3 of target treatment zone. ISCO costs vary widely based on the size of the treatment zone, the presence of DNAPL, and the oxidant delivery method. No case studies were encountered in which ISCO resulted in permanent reductions to microbial populations or sustained increases in metal concentrations in groundwater at the ISCO-treated site.

In Situ Chemical Oxidation Based on Hydrogen Peroxide: Optimization of Its Application to an Hydrocarbon Polluted Site

“…Rebound, defined as an increase in the contaminant concentrations observed in groundwater, following an initial reduction is a common occurrence observed at ISCO sites [31]. This phenomenon occurs when the oxidant degrades the dissolvedphase contaminant mass but not entirely the sorbed phase mass or free-phase mass.…”

“…The information include: the parameters to consider, metrics to assess performance or databases. In this context, Krembs et al [31] created a database with 242 ISCO projects from 42 US states and 7 nations and a list of selected publicly accessible ISCO case study resources.…”

“…Although rebound requires further remediation efforts [72], it can be used to find unknown areas with high sorbed and free-phase mass [31].…”

Efeitos Da Oxidação Por Persulfato Nas Propriedades Do Latossolo Vermelho

“…A oxidação química in situ (ISCO, do inglês in situ chemical oxidation) tem sido vista com grande interesse devido à sua eficiência e custo-benefício na remediação de solos e águas subterrâneas contaminados por diversos compostos orgânicos (BACIOCCHI et al, 2014;KREMBS et al, 2010;SEOL;. Esta técnica envolve a distribuição FELIX-NAVARRO et al, 2007;LIAO et al, 2014;LUO, 2014;OH;SHIN, 2014;WANG, C. W.;LIANG, 2014;WANG, Z.;YANG, 2014;ZHAO et al, 2014).…”

In-situ Chemical Oxidation for Volatile Organic Compounds Removal in Groundwater: A Pilot-scale Study

“…Soil texture, groundwater hydrology, and chemical agents have a decisive effect on the final oxidation effect, in addition to pH, oxidation-reduction potentials, and so on. Hence, the ISCO should be performed relying on an integrated evaluation which links site specific characterization tests and further pilot tests with feasibility studies at the lab and field scale [12]. This study is a beneficial attempt to examine the feasibility of ISCO of groundwater.…”