TranslateFormer Hardware Store Site — Adamsville
Project Year
2010
Project Duration
570 days (monitoring period)
Contaminants of Concern
Remediation Technologies Used
- • Chemical Oxidation (Sodium Persulfate)
- • Biological Mineralization
- • Zero-Valent Iron (ZVI) Suspension
- • Dual-Phase Treatment
Key Results
- ✓97% benzene reduction at MW-1/MW-1R
- ✓99% benzene reduction at MW-5
- ✓Sustained reducing conditions established
- ✓Cost-effective dual-phase approach
- ✓Long-term biological treatment enabled
A unique mix of chemical oxidation and facultative biologically based mineralization was used to degrade benzene, toluene, ethylbenzene and xylene compounds present in soil and groundwater at a hardware store site in Adamsville, Ohio.
The utilization of free radical chemistry was implemented in such a way as to extend the oxidant and free radical residuals. The injection program effectively introduced the remedial chemicals sodium persulfate, hydrogen peroxide and zero-valent iron directly into the soil and groundwater using injection wells and direct push technologies.
The injection program targeted a total of 2,502 square feet.
The first phase of the degradation program oxidizes VOCs via hydroxyl and sulfate free radicals, utilizing zero-valent iron as a catalyst for both reactions. This step is then followed by the enhancement of biological attenuation using the spent materials from the oxidation event to aid in facultative biological degradation of the dissolved phase compounds remaining after the oxidation event.
Materials Injected:
- 1,241 pounds of ZVI suspension in 700 gallons of water
- 5,180 pounds of sodium persulfate in ~2,825 gallons of oxidative solution
MW-1/MW-1R Results:
- Benzene: 97% reduction (4.2 to 0.14 ppm)
- Ethylbenzene: 20% reduction
- Total Xylenes: 49% reduction
MW-5 Results:
- Benzene: 95% reduction (7.0 to 0.36 ppm)
- Toluene: 70% reduction
- Ethylbenzene: 86% reduction
- Total Xylenes: 68% reduction
