DEPARTMENT OF THE ENVIRONMENT
Dispensations for water quality parameters granted under Article 13(1) of the Water (Jersey) Law 1972 as Amended
(Public)
Purpose of the Report
The Minister for Planning and Environment (The Minister) is requested to:
- Grant the application for dispensation of water quality parameters, with conditions, for the period 17 June 2016 to 17 June 2019.
Background
Under Article 12(1) of the Law as Amended, The Jersey New Waterworks Company Limited (Jersey Water) may in writing apply for a dispensation from the requirements of Paragraph 2 of the Schedule of the Law subject to a number of conditions including:
- that the dispensation is necessary to maintain a supply of water for domestic purposes;
- that a supply of water for those purposes cannot be maintained in the specified areas by any other reasonably practicable means; and
- that the supply of water in accordance with the dispensation does not constitute a potential danger to human health.
An application for dispensations from Jersey Water for Oxadixyl (a legacy pesticide which is no longer used) was received, in writing, by The Minister on 27 May 2016.
Under Article 13(1) of the Law as Amended, The Minister may grant an application for dispensation if, but only if, the Minister is satisfied that each of the conditions detailed above is established.
Under Article 19(1) of the Law as Amended, where any human health or public health related issues arise in relation to applications for dispensations, The Minister is required to consult with The Minister for Health and Social Services. This consultation has been undertaken.
Discussion
In February 2016 during routine testing, Jersey Water (the Company) discovered the presence of a legacy pesticide, oxadixyl, in water resources across the Island. Oxadixyl is highly soluble in water and is classed as moderately to highly persistent in water. The presence of oxadixyl was identified following the Company’s change of laboratory supplier and consequentially is likely to have been present in raw water at the time of its use as a fungicide and blight control for potatoes. Oxadixyl was banned for use in 2003. To our knowledge, it has not been used locally since, but continues to be used in other parts of the world.
Oxadixyl is present and above 0.1μg/L in a number of streams that feed the supply reservoirs and is also present in groundwater, particularly in the west of the Island. Following the identification of the presence of Oxadixyl in local waters both the Department and the Company have stepped up their monitoring programmes significantly. However, both parties continue to rely on a limited time series of data and consequentially are uncertain of the long-term behaviour and trend of this pesticide in raw water. Currently, concentrations in some streams continue to rise as rainfall and groundwater levels decrease as we approach summer, limiting any dilution capacity. Given that surface water is principally derived from groundwater any improvements in water quality are likely be slow.
The 0.1ug/l standard for individual pesticides prescribed within the Drinking Water Directive and the Law is a surrogate value and is not a health-based value. The advisory health limit for oxadixyl is 30μg/L for drinking water.
Val de la Mare reservoir, the Company’s key western resource, was out of service for a number of months. Recently the Company reached a crucial point when they have needed to bring it back into service to secure water supplies for the Island through the summer and early autumn. A Dispensation is needed to enable the Company to utilise Val de la Mare and manage their resources to supply their customers. The issue is exacerbated by the delay in the desalination plant upgrade.
There is no default treatment process for oxadixyl and it will therefore take a period of time for the Company to undertake laboratory tests, field trials and then, if necessary, procure and commission a suitable plant. Whilst this process has been started there continues to be a need to further monitor oxadixyl within raw water supplies to understand factors affecting its concentration in groundwater and surface water streams.
Once an effective treatment process has been identified, there may be the option of installing a temporary treatment unit. The feasibility of this will become clearer once treatment options are narrowed down.
Health implication of a dispensation
As required under Article 19(1), The Minister has consulted on the human or public health related issues arising from the dispensations with the Minister for Health and Social Services.
Comments by the MOH
In his consultation response dated 13 June 2016 The Minister for Health and Social Services confirmed that the dispensation and proposed conditions were acceptable.
Comments of Professor John Fawell MBE (independent advisor to the Company)
The 0.1μg/L standard in the Drinking Water Directive dates from the first Directive developed in 1984 and is based on the limit of detection by the then available methods for routine analysis as a surrogate zero. The policy position that pesticides should not be present in drinking water, which was the basis of this decision, is still maintained. This is not a health-based value and exceeding 0.1μg/L should not be interpreted in relation to health. WHO produces individual health-based values for pesticides but of course is unable to do so for all possible pesticides that are used around the world. However, the principle for developing health-based values for drinking water as stated by WHO provides the basis to be able to do so for any pesticide for which an ADI (Acceptable Daily Intake) is available.
Health-based values for individual pesticides in drinking water can be determined by using the ADI developed by an appropriate Authority. Normally this would be the WHO/FAO Joint Meeting on Pesticide Residues (JMPR) or the European Food Standards Agency (EFSA), however, as oxadixyl has not been evaluated by either of these Authorities the ADI developed by a National Regulatory Authority would be acceptable. The approach developed by WHO for the Guidelines for Drinking Water Quality is to assume a 60kg adult drinking two litres of water per day and allocating a proportion of the ADI to drinking water, depending on other sources of exposure. Generally the default used by WHO is 20% but for pesticides it will depend on the exposure from food. The allocation is then more likely to be 10% but in cases where there may be significant exposure from food it may be as low as 1%.
In the case of oxadixyl, it is apparent that exposure from food is low and EFSA have developed a maximum residue level (MRL) for treated crops that has been assessed for safety against the ADI produced by the French Authorities, which is the lowest of those available. This evaluation shows that exposure from the food chain is low with only 10% of the ADI being taken up by food. In view of the fact that oxadixyl is not used on Jersey the chances of exposure from food being significant is very small due to dilution of the imported food items in the total diet. Since exposure from food will not be high an allocation of 10% of the French ADI to drinking water in developing a health-based value would be appropriate and would still be conservative. On this basis the health based value for oxadixyl would be 30μg/L. The value based on a very precautionary 1% allocation of the most conservative (lowest) ADI to drinking water would be 3μg/L.
Long-term solutions
Treatment
There is no standard treatment process for oxadixyl and it will therefore take the Company a period of time to undertake laboratory tests, field trials and then, if necessary, procure and commission a suitable plant. The Company have already undertaken lab based trials using an enhanced version of the existing treatment process and are in consultation with key industry experts to develop a suitable process. There is a continued risk that any treatment process developed will not fit within the envelope of land of the existing treatment plant sites and further consideration and delay may result, whilst alternative options are investigated. The Company continue to gather temporal and spatial data and conduct research prior to a solution being identified and procured.
Once an effective treatment process has been identified there may be the option of installing a temporary treatment unit. The feasibility of this will become clearer once treatment options are narrowed down.
Departmental work The Department for the Environment continue to implement measures to safeguard water resources from pollution and are in the final stages of developing a Water Plan which will look to tackle the key pressures on the water environment, one of which is clearly pesticides. It is important that the Department continues its support, and in appropriate circumstances enhance its support (using the regulatory tools available to it), to the Company by undertaking activities to protect key water resources which Jersey Water rely on. This will reinforce the company’s ability to comply with the dispensation limit for Oxadixyl or any other parameter limit in those circumstance which are beyond the company’s control (i.e. a pollution incident). Such measures may range from bringing forward new regulation to control the use of pesticides and fertilisers to exercising powers under the Water Pollution (Jersey) Law 2000 in reaction to any specific events during the dispensation period which may threaten water quality.
Dispensation Conditions
The conditions of the dispensation are prescribed below:
PARAMETER: Oxadixyl
MAXIMUM ALLOWABLE CONCENTRATION (MAC): 0.3μg/L
DETAILS OF DISPENSATION
PERIOD OF DISPENSATION: 17 June 2016 to 17 June 2019
AREA OF SUPPLY: Whole Island distribution area
DISPENSATION CONDITIONS:
- Where any exceedence of Oxadixyl above 0.1μg/L occurs in treated water the Company are required to inform the Regulator of the circumstances surrounding that exceedance and any actions taken or to be taken to ensure the concentration of Oxadixyl in treated water does not breach the 0.3μg/L limit. The Company will inform the Regulator of any wider water resource supply and security considerations for the Island that limit their ability to act. Actions may include, but not be limited to, blending with other sources of supply, any available treatment, use of by-passes and dilution through the use of the well fields and/or desalination.
- The Company is required to investigate treatment options for Oxadixyl and will provide an update on progress to develop a treatment process, on a quarterly basis in a manner to be agreed with the Regulator. This will include the results of any treatment trials.
- The Company shall forward a monitoring plan of its raw water resources to establish and provide an understanding of the behaviour of oxadixyl in local waters over time and to inform any long-term strategy for managing levels of oxadixyl within the company’s raw water sources and consequentially any future need for dispensations. The results of the monitoring program should be forwarded to the Regulator every six months.
- In any situation whereby through the management of oxadixyl levels in supply, the Company becomes aware of a risk of breaching another parameter, the Company will consult with the Regulator and the Minister of Health and Social Services.
- The Company will keep the regulator informed of the progress and commissioning of the desalination plant, the planned reservoir by passes at Val de la Mare and Queen’s Valley and any other changes to infrastructure (either improvement or breakdown/failure/reservoir shutdown/water resource modelling etc.) that will either improve or lessen the ability of the Company to control levels of Oxadixyl in water supply.
- A copy of the treated water quality results will be forwarded to Environmental Health on a frequency to be agreed over the duration of the dispensation period.
- The Company will inform the Minister for the Environment of any of its raw water sources that may from time to time require specific safeguard from pollution in order to comply with the terms of this dispensation.
This dispensation can be modified or revoked in accordance with Article 16 of the Law
Recommendation
The Minister:
- Grant the application for dispensation of water quality parameters, with conditions, for the period 17 June 2016 to 17 June 2019.
Written by: Dr Tim du Feu, Director Environmental Protection
Approved by: Mr William Peggie, Director for Environment, Deputy Chief Officer
Ministerial Decision ref: MD--
16 June 2016