Reply to comment on “Geochemical heterogeneity and

Authors: Barbora Topinkova

Publish Date: 2009/05/05

Volume: 17, Issue: 4, Pages: 1029-1029

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Abstract

The indication of zones in Fig 5 of the subject article in accordance with the text should be as follows Zone I is Background Zone II is Reoxidation zone Zone III is Plume core and Zone IV is Plume fringe This mistake arose during the creation of Fig5 and the authors greatly apologize for thatThe presence of secondary magnetite is questioned in the Comment because of highly alkaline groundwater and precipitation of Fecarbonates These conditions and the secondary carbonate precipitation are typical for the plume core but the origin of the secondary magnetite was discussed with respect to the plume fringe Iron hydroxides firstly precipitate in the zone of the contaminant plume and are converted over the years via bacterial processes to goethite hematite or magnetite depending on the presence of specific microbial strains and FeII concentrations in groundwater These processes are described in papers by for example Hansel et al 2003The difference between δ34S in samples PJ500 358‰ and PJ519/5 36‰ is discussed in the subject article on page 973 This difference is well within the margin of error of the analytical method The authors of the Comment consider the explanation of the anomalous δ34S in the plume core impossible because of the pH range but extended mineralogical research found a large amount of iron and manganese precipitates that could create a wide surface feasible for sorption Over and above this explanation could be the consequence of local changes of advective flow These local inhomogenities were confirmed by granular analysis in the studied part of the aquifer Both alternatives are discussed in the subject articleThe authors of the subject article are the authors of the basic draft of the conceptual model that was presented at the CORONA project meeting in autumn of 2003 The report of Topinkova et al 2007 is based on data that were collected by all of its authors during field and laboratory work in 2002–2004 The report was submitted for publication in Hydrogeology Journal on the April 6 2005 The article cited in the Comment Vencelides et al 2007 was submitted for publication on the December 8 2005 and uses all data and background knowledge presented in the report of Topinkova et al 2007 These background data were obtained during the CORONA international project and the authors of both articles were members of the same research group Thus all comments about authorship are irrelevant

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