Communal Wastewater Treatment Plants’ Effectiveness, Management, and Quality of Groundwater: A Case Study in Indonesia

Round 1

Reviewer 1 Report

Overall evaluation:

This study focuses on the impact of wastewater treatment performance of sewage treatment plants on the quality of surrounding groundwater, and through qualitative and quantitative analysis of laboratory technical data and non-technical data from questionnaires, a water quality distribution map is drawn, and the main results are: sewage The total coliform parameters in the plant discharge water were proportional to the total coliform and E. coli concentrations in the surrounding groundwater. The reviewer has several major concerns about this manuscript. First, the purpose and findings of this study are not fully reflected in the abstract section; the practical significance of this study is also not fully described in the results section. The following are specific comments to be aware of.

1. Both the abstract and the background part of the article mention: "Public wastewater treatment plants are used as a source of pollution to analyze the relationship between the treatment effect of public wastewater treatment plants and groundwater quality". However, in the data analysis and conclusion part, it is emphasized: "The wastewater treatment plant has a certain treatment effect on wastewater, and is still an important measure to improve groundwater quality." Personally, I feel that the research purpose of the article does not match the research content. 

2. The summary part of the research results is too simplistic and one-sided. In this study, multiple water quality indicators such as sewage treatment plants and groundwater were detected and analyzed, but only microbial parameters were used in the abstract to reflect the relationship between sewage treatment plants and groundwater.

3. The main purpose of this study is: the effect of wastewater treatment performance of WWTP on groundwater quality. In the background part, a large amount of space is devoted to the operation status of the sewage treatment plant, and there is no further explanation on why the sewage treatment plant has become a new source of pollution and the possible ways to affect the groundwater quality.  

4. Line 37, no first line indentation. The same problem occurs many times in subsequent parts of the article.

5. Line 273, whether "Communal WWTP" should be changed to "CWWTP". The same problem occurs later in the article.

Author Response

Dear Reviewer 1,

Thank you very much for the items you pointed out in our manuscript. In response to your comments, we have changed many aspects of our manuscript. The title and abstract have been modified to align better with the manuscript. Some inconsistencies in word usage have also been cleared.

Reviewer 2 Report

With respect to lack of data in different region of the Indonesia and importance of the work. Unfortunately, I cannot accept this paper. There are numerous issue from English point of view to scientific and presentations. Authors need to significantly change the articles. I suggest to find a collaborators for their article to help shaping the manuscript. Particularly, results are poorly presented.

Author Response

Dear Reviewer 2,

Thank you very much for your comments.

We do understand it would be better to analyze more locations in Indonesia. However, due to some restrictions during the Covid-19 pandemic, we cannot do that. However, we tried our best to add more discussion with relevant works from different areas of study in Indonesia.

We did collaborative work in this study and we believe at our best, the analysis carried is sufficient with the context of the study location.

Reviewer 3 Report

The work sent for review raises an important issue related to the protection of groundwater quality. There are still areas where water and sewage management is not properly organized, which makes the quality of water available to residents inadequate. Therefore, the work should be published after correcting / supplementing:

- an explanation should be given how the wastewater is treated in the treatment plants concerned,

- how many times were water and sewage samples taken for testing (inflow and outflow from the CWWTPs, monitoring wells),

- concentration of BOD/COD (rows 211-225 et seq.) - BOD and COD are indicators, they are not present in water / wastewater, so we cannot talk about their concentration,

- the Authors collected the results of studies on eight sewage treatment plants and twenty monitoring wells. Were there other sources of pollution in the study area? Do the distances between research points allow for a reliable presentation of research results in the form of spatial distribution?

- how can the efficiency of removing microbiological contamination from municipal wastewater be improved?

Author Response

Dear Reviewer 3,

Thank you very much for your comments on our manuscript.

We have added some revisions regarding the method, including sampling which in this study follows the Indonesian National Standard 6989.59 of 2008. We also add suggestion on new method for microbiological removal in the discussion.

Reviewer 4 Report

The ms titled The Effect of a Communal Wastewater Treatment Plant (CWWTP) on The Quality of Groundwater: A Case Study in Indonesia submitted by Widodo Brontowiyono is very interesting. However, necessary modifications are necessary before acceptance for publication.

1.        Line 19-33, Abstracts: The methodology needs to be supplemented and perfected. The results and conclusions need to be supplemented. It needs to be clearly stated whether the sewage plant affects groundwater quality and causes

2.        Figures are not very clear and needs to be modified

3.        Some captions (Fig.5,6,7,8,9) are ambiguous and needs additional information

4.        There are many language problems (Line 71, 74-76, 118-121, 302-315,322-324,330, 339,405,436), which need to be corrected.

5.     The conclusion needs to be rewritten. needs to be clearly stated whether the sewage plant affects groundwater quality and causes. 

Author Response

Dear Reviewer 4,

Thank you very much for your comments.

We have changed some aspects of the manuscript, including the title, abstract, figure captions, and others. We hope this meets your comments.