In-situ methods for selective groundwater selenium remediation

Overview

This solution offers an advanced in-situ method for the selective remediation of selenium-contaminated groundwater, addressing the challenge of arsenic mobilization. By injecting a biodegradable carbon source, this method stimulates native microbes to create reducing conditions, transforming selenate into insoluble selenium. A stabilizing agent is also used to bind arsenic, preventing its mobilization. This approach enhances natural attenuation, requires minimal maintenance, and produces no hazardous waste, making it ideal for selenium-arsenic co-contaminated sites.

Technical specifications

• Biodegradable carbon source: Injected to stimulate native microbes and create mildly reducing conditions.
• Stabilizing agent: Iron- or phosphate-based agents added to bind released arsenic.
• Operation: Conducted entirely in-situ without water extraction, using injection wells or passive barriers.
• Monitoring: Field monitoring allows for adjustments in carbon and stabilizer inputs.
• Deployment: Options include injection wells or permeable reactive barriers for passive treatment.

Technology readiness level

This technology has reached a TRL of 9, indicating it has been fully developed and validated. Proof-of-concept studies are underway to further refine the approach, with plans for pilot injections and comprehensive monitoring to ensure efficacy and compliance.