Raggatt leachate treatment

Summary

A request was made for details on chemical reactions, dilution practices, and sampling data regarding Raggatt leachate treatment. The Department of Environment, Food and Agriculture disclosed that the treatment relies on physical adsorption rather than chemical reactions, provided specific contaminant levels and sampling dates, but refused to create new explanatory information for some questions.

Key Facts

• The mechanism for reducing PCB contaminants is physical adsorption onto sewage sludge solids, not a chemical reaction.
• The intention of the treatment is to remove contaminants, not simply dilute them.
• UK Environment Agency guidance suggests a 98% reduction in contaminants can be achieved through the sewage treatment process.
• Raggatt leachate was sampled 7 occasions between 2015 and 2017.
• The Department stated that creating explanatory answers for questions not based on held information is not required under the Freedom of Information Act.

Data Disclosed

• 1.437 ng/l
• 0.192 ng/l
• 2.85 ng/l
• July 2017
• 2015
• 2017
• 64kg
• 98%
• 7 occasions
• 1 ng/l

Exemptions Cited

• Section 8(3) of the Freedom of Information Act (no requirement to create or derive information)
• Information not held by the public authority

Original Request

According to Hansard of May 15, 2018 Mr Boot stated that the contaminants present in the Raggatt leachate could be reduced by sewage treatment through the new plant. Please would you let me know the chemical reaction by which each of the contaminants could be neutralised or rendered harmless in a sewage treatment plant? If the intention is simply to dilute the contaminants, please would you explain why the proposed treatment would be an improvement on the present practice of dumping the Raggatt leachate into the sewage outfall piping? Please would you let me know how often the Raggatt leachate is sampled, the highest level recorded of each of the contaminants and the date when those levels were recorded.

Data Tables (1)

Full Response Text

Freedom of Information Co-ordinator Corporate Services Directorate Thie Slieau Whallian, Foxdale Road, St John’s, Isle of Man, IM4 3AS Tel no (01624) 685854 Fax no (01624 685851 Email: defa@gov.im www.gov.im

Our ref: 500235 9 August 2018

Dear ###

We write further to your request which was received on 11 June 2018 and which states:

"According to Hansard of May 15, 2018 Mr Boot stated that the contaminants present in the Raggatt leachate could be reduced by sewage treatment through the new plant. Please would you let me know the chemical reaction by which each of the contaminants could be neutralised or rendered harmless in a sewage treatment plant? If the intention is simply to dilute the contaminants, please would you explain why the proposed treatment would be an improvement on the present practice of dumping the Raggatt leachate into the sewage outfall piping? Please would you let me know how often the Raggatt leachate is sampled, the highest level recorded of each of the contaminants and the date when those levels were recorded."

While our aim is to provide information whenever possible, in this instance the public authority does not hold or cannot, after taking reasonable steps to do so, find some of the information that you have requested. Your questions have been answered individually below. 1. Please would you let me know the chemical reaction by which each of the contaminants could be neutralised or rendered harmless in a sewage treatment plant? The Department does not hold or cannot, after taking reasonable steps to do so, find the information requested. The Department can explain however, that the most significant “contaminants” that cause concern are the WHO 12 (toxic) and EC7 (persistent) congeners of PCBs which exhibit toxic and persistent effects in the environment. The mechanism by which such substances are reduced is not chemical, it is physical, by adsorption onto sewage sludge solids which are then physically removed from the effluent stream prior to its discharge to the environment. 2. If the intention is simply to dilute the contaminants, please would you explain why the proposed treatment would be an improvement on the present practice

of dumping the Raggatt leachate into the sewage outfall piping? The Department does not hold or cannot, after taking reasonable steps to do so, find the information requested. The Department can explain however, that the intention is not to dilute the contaminants but to remove them via the sewage sludge solids as described above. In the existing leachate the mean concentration of the EC7 (persistent) congeners (of PCBs) is 1.437 ng/l and the WHO 12 (toxic) congeners is 0.192ng/l. That is 1.437 and 0.192 millionths of a gram per cubic metre of leachate. UK Environment Agency guidance states that a 98% reduction in such contaminants could be achieved through the sewage treatment process. This would result in undetectable levels in the discharge. To put these levels into context, even at pre-treatment levels only one of the EC7 congeners was marginally above the 1 ng/l reporting value that was until recently required of laboratories by the UK Environment Agency. None of the WHO 12 congeners exceeded this reporting value. It is worth pointing out that excedance of a reporting value does not necessarily represent a breach of environment or safety standards, but is the smallest amount that ordinarily would be declared. To add further context, the most recent data available records that in 2015 up to 64,000 tonnes [6 Aug 2018 ' a typographical error was spotted and this should read '64kg' (i.e. 64,000 grams)] of PCBs entered the Irish Sea via UK rivers. 3. Please would you let me know how often the Raggatt leachate is samples [sic], the highest level recorded of each of the contaminants and the date when those levels were recorded? The Raggatt leachate was sampled for the contaminants described above on 7 occasions between 2015 and 2017. The highest levels recorded were 2.85ng/l for the EC7 congeners in July 2017 and 0.192 ng/l for the WHO 12 congeners in July 2017. Two of the above questions do not request information that is held; rather they are questions that require explanatory answers to be created and that is not the purpose of the Freedom of Information Act (the Act). The Act allows Isle of Man residents access to information that is already held by a Public Authority. Section 8(3) of the Act states: Nothing in this Act requires a public authority to — (a) create or derive information from information that it holds; (b) undertake research into, or analysis of, information that it holds; In order to provide as much information as possible, however, and despite the Act not obliging the Department to do so, further explanation has been given under each of your questions. Further information In addition to this, a number of reports have been commissioned by various bodies over a period of years which have been and are, used to determine current and future

policy to find the best practical environmental option to manage the discharge. We are currently assessing the possibility of publishing some or all of these reports or extracts from them. Please quote the reference number 500235 in any future communications.

Your right to request a review

If you are unhappy with this response to your freedom of information request, you may ask us to carry out an internal review of the response, by completing a complaint form and submitting it electronically or by delivery/post.

An electronic version of our complaint form can be found by going to our website at https://services.gov.im/freedom-of-information/Review . If you would like a paper version of our complaint form to be sent to you by post, please contact me and I will be happy to arrange for this. Your review request should explain why you are dissatisfied with this response, and should be made as soon as practicable. We will respond as soon as the review has been concluded.

If you are not satisfied with the result of the review, you then have the right to appeal to the Information Commissioner for a decision on; 1. Whether we have responded to your request for information in accordance with Part 2 of the Freedom of Information Act 2015; or 2. Whether we are justified in refusing to give you the information requested.
In response to an application for review, the Information Commissioner may, at any time, attempt to resolve a matter by negotiation, conciliation, mediation or another form of alternative dispute resolution and will have regard to any outcome of this in making any subsequent decision. More detailed information on your right to a review can be found on the Information Commissioner’s website at www.inforights.im. Should you have any queries concerning this letter, please do not hesitate to contact me. Further information about freedom of information requests can be found at www.gov.im/foi.

I will now close your request as of this date.

Yours sincerely

Freedom of Information Co-ordinator Corporate Services Directorate Thie Slieau Whallian, Foxdale Road, St John’s, Isle of Man, IM4 3AS Tel no (01624) 685854 Fax no (01624 685851 Email: defa@gov.im www.gov.im

Our ref: 500235 6 July 2018

Dear ###

This request is being handled under the Freedom of Information Act 2015.

We write further to your request which was received on 11th June 2018 and which states:

"According to Hansard of May 15, 2018 Mr Boot stated that the contaminants present in the Raggatt leachate could be reduced by sewage treatment through the new plant. Please would you let me know the chemical reaction by which each of the contaminants could be neutralised or rendered harmless in a sewage treatment plant? If the intention is simply to dilute the contaminants, please would you explain why the proposed treatment would be an improvement on the present practice of dumping the Raggatt leachate into the sewage outfall piping? Please would you let me know how often the Raggatt leachate is sampled, the highest level recorded of each of the contaminants and the date when those levels were recorded."

While our aim is to provide information whenever possible, in this instance the public authority does not hold or cannot, after taking reasonable steps to do so, find some of the information that you have requested. Your questions have been answered individually below. 1. Please would you let me know the chemical reaction by which each of the contaminants could be neutralised or rendered harmless in a sewage treatment plant? The Department does not hold or cannot, after taking reasonable steps to do so, find the information requested. The Department can explain however, that the most significant “contaminants” that cause concern are the WHO 12 (toxic) and EC7 (persistent) congeners of PCBs which exhibit toxic and persistent effects in the environment. The mechanism by which such substances are reduced is not chemical, it is physical, by adsorption onto sewage sludge solids which are then physically removed from the effluent stream prior to its discharge to the environment.

1. If the intention is simply to dilute the contaminants, please would you explain why the proposed treatment would be an improvement on the present practice of dumping the Raggatt leachate into the sewage outfall piping? The Department does not hold or cannot, after taking reasonable steps to do so, find the information requested. The Department can explain however, that the intention is not to dilute the contaminants but to remove them via the sewage sludge solids as described above. In the existing leachate the mean concentration of the EC7 (persistent) congeners (of PCBs) is 1.437 ng/l and the WHO 12 (toxic) congeners is 0.192ng/l. That is 1.437 and 0.192 millionths of a gram per cubic metre of leachate. UK Environment Agency guidance states that a 98% reduction in such contaminants could be achieved through the sewage treatment process. This would result in undetectable levels in the discharge. To put these levels into context, even at pre-treatment levels only one of the EC7 congeners was marginally above the 1 ng/l reporting value that was until recently required of laboratories by the UK Environment Agency. None of the WHO 12 congeners exceeded this reporting value. It is worth pointing out that excedance of a reporting value does not necessarily represent a breach of environment or safety standards, but is the smallest amount that ordinarily would be declared. To add further context, the most recent data available records that in 2015 up to 64,000 tonnes of PCBs entered the Irish Sea via UK rivers.
2. Please would you let me know how often the Raggatt leachate is samples [sic], the highest level recorded of each of the contaminants and the date when those levels were recorded? The Raggatt leachate was sampled for the contaminants described above on 7 occasions between 2015 and 2017. The highest levels recorded were 2.85ng/l for the EC7 congeners in July 2017 and 0.192 ng/l for the WHO 12 congeners in July 2017. Two of the above questions do not request information that is held; rather they are questions that require explanatory answers to be created and that is not the purpose of the Freedom of Information Act (the Act). The Act allows Isle of Man residents access to information that is already held by a Public Authority. Section 8(3) of the Act states: Nothing in this Act requires a public authority to — (a) create or derive information from information that it holds; (b) undertake research into, or analysis of, information that it holds; In order to provide as much information as possible, however, and despite the Act not obliging the Department to do so, further explanation has been given under each of your questions. Further information

In addition to this, a number of reports have been commissioned by various bodies over a period of years which have been and are, used to determine current and future policy to find the best practical environmental option to manage the discharge. We are currently assessing the possibility of publishing some or all of these reports or extracts from them. Please quote the reference number 500235 in any future communications.

Your right to request a review

If you are unhappy with this response to your freedom of information request, you may ask us to carry out an internal review of the response, by completing a complaint form and submitting it electronically or by delivery/post.

An electronic version of our complaint form can be found by going to our website at https://services.gov.im/freedom-of-information/Review . If you would like a paper version of our complaint form to be sent to you by post, please contact me and I will be happy to arrange for this. Your review request should explain why you are dissatisfied with this response, and should be made as soon as practicable. We will respond as soon as the review has been concluded.

If you are not satisfied with the result of the review, you then have the right to appeal to the Information Commissioner for a decision on; 1. Whether we have responded to your request for information in accordance with Part 2 of the Freedom of Information Act 2015; or 2. Whether we are justified in refusing to give you the information requested.
In response to an application for review, the Information Commissioner may, at any time, attempt to resolve a matter by negotiation, conciliation, mediation or another form of alternative dispute resolution and will have regard to any outcome of this in making any subsequent decision. More detailed information on your right to a review can be found on the Information Commissioner’s website at www.inforights.im. Should you have any queries concerning this letter, please do not hesitate to contact me. Further information about freedom of information requests can be found at www.gov.im/foi.

I will now close your request as of this date.

Yours sincerely