Quantitative Assessment of Long-Term Abiotic Transformation Rates of Chlorinated Solvents - Phase 1
Abstract
This limited scope study focused on developing a quantitative tool to assess the rates of long-term abiotic transformation occurring at sites contaminated by chlorinated solvents including tetrachloroethene (PCE) and trichloroethene (TCE). Abiotic dechlorination of PCE and TCE by naturally present or biogeochemically augmented iron minerals (e.g., mackinawite and green rust) is an important process during natural attenuation (NA) of chlorinated ethenes. Although abiotic reduction of TCE and PCE offers cleaner transformation pathways with less accumulation of undesirable intermediates, evidence supporting abiotic degradation in field studies has been difficult to establish. Acetylene is a major product of PCE and TCE reduction by reactive minerals and is an indicator molecule of abiotic degradation. However, the potentially slow rate of acetylene generation and its rapid loss due to mineral adsorption or biological assimilation make it hard to detect at sites undergoing natural attenuation. In this project, the team aimed to develop a sensitive and robust device that can be deployed in situ to selectively accumulate acetylene over a field relevant time scale. The acetylene collected was quantified using standard instrumental analyses after the sampling activity, and the results were expected to inform the rates and extents of abiotic transformation of chlorinated ethenes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 2023
- Accession Number
- AD1221380
Entities
People
- Bruce E. Koel
- Weile Yan
Organizations
- Princeton University
- University of Massachusetts Lowell