BIO-TRANSFORMERS
The primary CFC anaerobic biotransformation pathway, wherein chloride is replaced by a hydrogen ion.
What is hydrogenolysis?
Defined as δ13C, this parameter represents the ratio between heavy and light isotopes present in a sample relative to a reference standard.
What is the isotopic carbon signature?
According to Henry’s Law, what is the process driving transport in groundwater?
What is dissolution?
The field site studied in this paper was located in this U.S. state.
What is New Jersey?
CFCs contribute to this global environmental issue which allows for greater intrusion of harmful UV rays.
What is ozone layer depletion?
The name of this proprietary microbial culture, derived from a contaminated site and used to test anaerobic degradation of CFCs.
What is SC01?
Since lighter isotopes like ¹²C react faster, the remaining compound becomes enriched in this heavier carbon isotope.
What is ¹³C?
CFC-113 and CFC-11 were present at the study site in this form, dissolved in groundwater, stemming from a legacy source.
What are DNAPLs (dense nonaqueous phase liquids)?
CFC-11, CFC-113, CFC-114 and HCFC-123a δ13C values as reported in Table 1 are comparable to the feedstocks of this industry.
What is the petroleum industry?
Upon being released into the atmosphere, free chlorine from CFCs binds to this atom, decreasing the ozone content.
What is free oxygen?
This equation, used to relate the fraction of CFC remaining to its isotopic enrichment during biotransformation.
What is the Rayleigh equation?
Defined as ε, this parameter reflects changes in the isotopic signature of a compound of interest.
What is the enrichment factor?
The preferred remediation strategy for CFC transformation in the subsurface, according to authors.
What is in-situ biotransformation?
The significantly higher degradation of CFC-11 compared to CFC-113 was attributed to this factor.
What is microbial culture history?
Presence of hydrogen allows for oxidation to nonvolatile products in this atmospheric layer, a major sink of HCFCs.
What is the trophosphere?
CFC-113 did not show δ¹³C shifts in the field, suggesting this.
What is "no significant biotransformation occurred"?
Relative to the reference standard, an increasingly negative δ13C represents this with respect to carbon-13.
What is depletion in 13C?
This quantitative parameter describes how easily a fluid can move through the subsurface, not to be confused with electrical.
What is hydraulic conductivity?
CFC-112 was not included in the study because it is less commonly used than CFC-11 and CFC-12 and for one other reason.
What is "because it was not present at the field site"?
Using CSIA allows for this, enhancing the understand of how chemicals interact in natural environments.
What is the evaluation of transformation?
This is one reason why knowing the δ¹³C of pure-phase CFCs is critical for interpreting field data.
What is "avoiding misinterpretation of degradation vs. source signatures"?
Evidence for transformation may be present due to enrichment of 13C in parent compounds and this in daughter products.
What is depletion in 13C?
Hydraulic head tests indicated that the entire vertical sequence was this, meaning that water (and CFCs), can travel between soil layers.
What is hydraulically connected?
The maximum possible EoT, or Extent of Transformation, was highest at this location, ranging from 77-86%.
What is location E14-M01?
Evidence for anaerobic dechlorination of CFC-11 to HCFC-21 makes in-situ transformation a feasible stratgey to lead to what fate?
What is full destruction of CFCs?