Douglas M. Mackay

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGroundwater contamination: pump-and-treat remediationDouglas M. Mackay and John A. CherryCite this: Environ. Sci. Technol. 1989, 23, 6, 630–636Publication Date (Print):June 1, 1989Publication History Published online1 May 2002Published inissue 1 June 1989https://doi.org/10.1021/es00064a001RIGHTS & PERMISSIONSArticle Views5956Altmetric-Citations588LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (6 MB) Get e-Alerts Get e-Alerts

A large‐scale field experiment on natural gradient transport of solutes in groundwater has been conducted at a site in Borden, Ontario. Well‐defined initial conditions were achieved by the pulse injection of 12 m 3 of a uniform solution containing known masses of two inorganic tracers (chloride and bromide) and five halogenated organic chemicals (bromoform, carbon tetrachloride, tetrachloroethylene, 1,2‐dichlorobenzene, and hexachloroethane). A dense, three‐dimensional array of over 5000 sampling points was installed throughout the zone traversed by the solutes. Over 19,900 samples have been collected over a 3‐year period. The tracers followed a linear horizontal trajectory at an approximately constant velocity, both of which compare well with expectations based on water table contours and estimates of hydraulic head gradient, porosity, and hydraulic conductivity. The vertical displacement over the duration of the experiment was small. Spreading was much more pronounced in the horizontal longitudinal than in the horizontal transverse direction; vertical spreading was very small. The organic solutes were retarded in mobility, as expected.

The long‐term behavior of five organic solutes during transport over a period of 2 years in ground water under natural gradient conditions was characterized quantitatively by means of moment estimates. Total mass was conserved for two of the organic compounds, carbon tetrachloride and tetrachloroethylene, while the total mass declined for three other compounds, bromoform, 1,2‐dichlorobenzene, and hexachloroethane. The declines in mass for the latter three compounds are interpreted as evidence of transformation of the compounds. Retardation factors for the organic solutes, relative to chloride, ranged from 1.5 to 9.0, being generally greater for the more strongly hydrophobic compounds. The retardation is attributed to sorption. The apparent retardation factor increased markedly for all compounds over the duration of the experiment, by as much as 150%. Results from temporal and spatial sampling were in good agreement when compared at the same scale of time and distance.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTransport of organic contaminants in groundwaterDouglas M. Mackay, Paul V. Roberts, and John A. CherryCite this: Environ. Sci. Technol. 1985, 19, 5, 384–392Publication Date (Print):May 1, 1985Publication History Published online1 May 2002Published inissue 1 May 1985https://pubs.acs.org/doi/10.1021/es00135a001https://doi.org/10.1021/es00135a001research-articleACS PublicationsRequest reuse permissionsArticle Views2056Altmetric-Citations210LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

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