ANAEROBIC TRANSFORMATION OF CHLORINATED ALIPHATIC-HYDROCARBONS IN A SAND AQUIFER BASED ON SPATIAL CHEMICAL-DISTRIBUTIONS

Semprini, L; Kitanidis, PK; Kampbell, DH; Wilson, JT

HERO ID

1968777

Reference Type

Journal Article

Year

1995

Language

English

HERO ID 1968777
In Press No
Year 1995
Title ANAEROBIC TRANSFORMATION OF CHLORINATED ALIPHATIC-HYDROCARBONS IN A SAND AQUIFER BASED ON SPATIAL CHEMICAL-DISTRIBUTIONS
Authors Semprini, L; Kitanidis, PK; Kampbell, DH; Wilson, JT
Journal Water Resources Research
Volume 31
Issue 4
Page Numbers 1051-1062
Abstract We estimated the distribution of chlorinated aliphatic hydrocarbons (CAHs) from groundwater samples collected along three transects in a sand aquifer. Trichloroethylene (TCE) leaked and contaminated the aquifer probably more than a decade before we collected the measurements. The data show significant concentrations of TCE, cis-1,2-dichloroethylene (c-DCE), vinyl chloride (VC), and ethene. We attributed DCE, VC, and ethene to the reductive dehalogenation of TCE. The CAH concentrations varied significantly with depth and correlate with sulfate and methane concentrations. Anoxic aquifer conditions exist with methane present at relatively high concentrations at depth. High concentrations of TCE correspond with the absence of methane or low methane concentrations, whereas products of TCE dehalogenation are associated with higher methane concentrations and low sulfate concentrations. Indications are that the dechlorination of TCE and DCE to VC and ethene is associated with sulfate reduction and active methanogenesis. TCE dechlorination to DCE is likely occurring under the less reducing conditions of sulfate reduction, with further reductions to VC and ethene occurring under methanogenic conditions. We estimated that about 20% of TCE has dechlorinated to ethene. The analysis of the data enhanced our knowledge of natural in situ transformation and transport processes of CAHs.
Doi 10.1029/94WR02380
Wosid WOS:A1995QQ32000024
Url https://search.proquest.com/docview/13657563?accountid=171501
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword Ethylene; Spatial; Aqualine Abstracts