Remediation of Benzene and 1,2-Dichloroethylene in Groundwater by Funnel and Gate Permeable Reactive Barrier (FGPRB): A Case Study

Round 1

Reviewer 1 Report

This study reported the impact of funnel and gate permeable reactive barrier (FGPRB) on pollutants and groundwater dynamic conditions. The case study is worthy of attention, yet I don’t think the authors clearly presented the novelty and value of this research. The current organization of the manuscript lacks a clear objective or hypothesis, and the manuscript somehow reads like a report. Please see my detailed comments below.

1. The authors should fairly comment on the technologies in the Introduction. Each technology has its own advantages and drawbacks.
2. The experimental methods need to be more specific, such as pollution analysis methods and instruments used.
3. It is recommended that the authors discuss how the pollutants are removed. Adsorption or degradation?
4. Line 63-64: the sentence “…little attention is paid to the changes of groundwater velocity and solute transport velocity in the long-term operation process.” has no references to support.
5. Many different barrier thicknesses and permeability coefficients are set in this paper, but the conclusion is that these different cases have no obvious influence on the results. Thus, maybe this part should not be described emphatically.
6. FGPRB would obvisouly affect groundwater dynamic conditions. However, there are no quantitative and novel results about the impact of FGPRB on groundwater dynamic conditions.
7. The conclusion merely described experimental phenomena.
8. D5 is marked as D3 in Figure 3. The clarity of this figure is not enough, so it is suggested to redraw and improve it.
9. The readability of figures is poor, such as small font size in fig 4 and fig 5.
10. 5: The time scales shouldn’t begin with negative number.
11. Line 43: there is PRB as the abbreviation of permeable reactive grid, it should be PRG.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript deals with the "Remediation of organic contaminants from water by Funnel and gate permeable reactive barrier(FGPRB)".

Polycyclic aromatic hydrocarbons (PAHs) are organic pollutants produced by anthropogenic activities associated with industrialization and urbanization, as well as through natural activities. To date, over 400 kinds of PAHs and their ramifications have been identified. PAHs are a group of hazardous organic compounds comprising of two or more benzene rings bonded in linear, angular of cluster arrangements (https://doi.org/10.1016/j.scitotenv.2019.133971). 

Conventional water and wastewater treatment methods fail in removal of these pollutants from water bodies; therefore, researchers have tried to find new methods.

 

1. Page 1, Line 19; "..well R2.." What is R2? Before using abbreviation, you need to use full name.

 

2. Page 2, Line 65; "Huang et al[15] carried out pilot test, treated NH4+-N polluted groundwater with zeolite" Ammonia?? It is not related to your study! mention the organic pollutants removal!

 

3. Page 2, Line 65; "Malini et al[16] used PRB with ZVI filler to remove As(V) contaminated" Metals!?! Same comments as above!

 

4. Page 2, Line 71; "(1) Evaluating the degradation effect of FGPRB on pollutants" What kinds of pollutants?! benzene and 1, 2-dichloroethylene? The aims should be so clear.

 

5. A legend should be drawn for Fig 2. What is U1? What is D5?...

 

6. Quality of Fig1 should be improved.

 

7. How did you test the "Benzene and 1, 2-dichloroethylene"?

 

8. There is no strong discussion!! You just presented your findings! You need to compare them with previous studies, and justify them!

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have addressed my comments.

Reviewer 2 Report

Reviewers' comments have been addressed.