In Situ Bioremediation of a Chlorinated Hydrocarbon Plume: A Superfund Site Field Pilot Test
Round 1
Reviewer 1 Report
I do find this work interesting. However the manuscript in my opinion needs improvement. This is difficult to understand clearly the goal of the article. I recommend to make the manuscript simpler, by choosing main results and describe them. The goal of the research, description of methods and results presented in the form of tables or figures should be more consistent. Discussion is very poor.
Specific comments:
Line 106 and later in the whole manuscript – you should use SI metric system – so, centimeters or meters instead of feets; dm3 instead of gallons, etc.
Line 199 – “sampling” two times
Material and methods are really complicated and difficult to understand – I suggest to prepare graphical scheme which would show what exact treatments were the base of the article and what analyses were performed, how many times, etc. It will make the article much easier to understand.
The results presented as Tables or figures should be compatible with the analyses described in material and methods. Please describe in material and methods only these analyses which were presented as a results – so only % of VOC and total VOC concentration or if the analyses were performed and described in Material and methods, the results should be shown in the form of Figures and Tables (not only as a text). Do not describe analyses which were not presented in the Results section. Moreover, the analyses presented in the results section must be described in Material and methods in details (method of analysis, equipment, etc.). I did not find for example in material and methods detailed description of VOC analyses which are main results, presented as figures 3 to 9.
In how many repetitions the samples were taken?
Is it possible to compare the results using some statistical methods?
Discussion should refer also to the results of other authors on similar topic.
Author Response
Line 106 and later in the whole manuscript – you should use SI metric system – so, centimeters or meters instead of feets; dm3 instead of gallons, etc.
Response: All units were converted to SI unit. English unit is shown in parentheses for reference.
Line 199 – “sampling” two times
Response: Extra “sampling” is removed.
Material and methods are really complicated and difficult to understand – I suggest to prepare graphical scheme which would show what exact treatments were the base of the article and what analyses were performed, how many times, etc. It will make the article much easier to understand.
Response: Two schematic figures (Figure 3 and Figure 4) and summary table (Table 1) were added.
The results presented as Tables or figures should be compatible with the analyses described in material and methods. Please describe in material and methods only these analyses which were presented as a results – so only % of VOC and total VOC concentration or if the analyses were performed and described in Material and methods, the results should be shown in the form of Figures and Tables (not only as a text). Do not describe analyses which were not presented in the Results section. Moreover, the analyses presented in the results section must be described in Material and methods in details (method of analysis, equipment, etc.). I did not find for example in material and methods detailed description of VOC analyses which are main results, presented as figures 3 to 9.
Response: Material and method section was reformatted and reduced significantly to be compatible with the results as a review suggested. Additional references regarding analytical methods were added.
In how many repetitions the samples were taken?
Response: Duplicate or triplicated samples were no corrected from the wells all the time, except for duplicates in 20% of the sample sets for sampling/laboratory QAQC requirements.
Is it possible to compare the results using some statistical methods?
Response: As a reviewer suggested, a trend in the decline of cVOC was evaluated using Mann-Kendall (ProUCL) and presented in discussion section.
Discussion should refer also to the results of other authors on similar topic.
Response: Additional reference of related topics were added.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The article presents the results of pilot-scale trials on bioremediation of groundwater polluted with chloroorganic compounds. The work possesses high scientific and practical significance and may be accepted. Nevertheless, the manuscript should be improved.
The Introduction contain only 5 references and does not provide any information of the topic of the work. The introduction should contain information on the similar research examples (laboratory, pilot-scale trials), mechanisms of bioremediation used (microbial groups and metabolic pathways involved in PCE destruction, etc).
Thus, the introduction should be extenede and additional references are required.
Author Response
The article presents the results of pilot-scale trials on bioremediation of groundwater polluted with chloroorganic compounds. The work possesses high scientific and practical significance and may be accepted. Nevertheless, the manuscript should be improved.
Response: Material and method section was reformatted significantly to provide additional clarification for pilot test procedure and sampling program. Two schematic figures (Figure 3 and Figure 4) and summary table (Table 1) were added. Additional reference regarding analytical methods were added.
The Introduction contain only 5 references and does not provide any information of the topic of the work. The introduction should contain information on the similar research examples (laboratory, pilot-scale trials), mechanisms of bioremediation used (microbial groups and metabolic pathways involved in PCE destruction, etc). Thus, the introduction should be extenede and additional references are required.
Response: As a reviewer suggested, additional reference of related topics was added and Introduction was extended.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The manuscript was partly improved. Still, I do not see any references in Discussion section. I mean : references to the similar research conducted by other authors. If they are not available - it should be written. In this form the manuscript does not have broader meaning. It is limited to this specific location and situation.
Author Response
As commented, eight (8) new references for a similar research conducted by other authors were added in Discussion section. Also other minor edits were performed to improve consistency and readability. I noticed that track changes shift the location of figures which are not representative of where they reside in the document. For this reason, clean copy (no track changes) manuscript will be submitted upon request.
Author Response File: Author Response.docx
Reviewer 2 Report
The article may be accepted as authors have improved the manuscript according to the reviewer's recommendations.
Author Response
The article may be accepted as authors have improved the manuscript according to the reviewer's recommendations. Also, I noticed that track changes shift the location of figures which are not representative of where they reside in the document. For this reason, clean copy (no track changes) manuscript will be available upon request.
Author Response File: Author Response.docx
