Project Appreciation and Objectives
Performance data for the removal of pesticides, particularly the urons, acid herbicides and triazine compounds, were developed in the 1990s and resulted in widespread water treatment capital programmes. Since then, other micropollutants,(e.g. Chlorpyrifos, Clopyralid, Terbuthyazine, Metolachlor, Glyphosate, Carbetamide) have become a cause for concern. Monitoring, required by the Water Framework Directive, will show that such micropollutants, including priority substances, are present in source waters. There is a need to establish whether water treatment provides an adequate barrier to these and what additional treatment might be required. However, there is little relevant performance data available to meet this need.
The programme's objectives were to obtain performance data for an agreed list of micropollutants and to use this to determine future treatment requirements.
Benefits to Clients
- Identification of water treatment barriers to emerging, new organic micropollutants.
- Confidence in existing treatment.
- Evidence to justify future capital and operational expenditure on new or extended treatment.
- Draw up a short-list based primarily on existing or likely future regulatory requirements, usage, environmental occurrence and discussion with contributors, European Crop Protection Association, ADAS, Defra and European Research organisations.
- Review published and grey data and summarise likely treatment performance where known. Where this information is absent determine what investigations are needed and estimate likely costs.
- Perform laboratory-based tests on agreed selected compounds to evaluate the relative treatment performances, particularly for activated carbon and oxidants.
- If appropriate, a follow-on study is envisaged to perform laboratory or pilot plant trials on selected compounds, to provide more detailed information for process selection, design and operation.
- A summary of each selected micropollutant indicating: behaviour in treatment and providing process performance and selection recommendations.
- Defined programmes for further investigations with a costed programme.
- Detailed report on the investigations with an update of the Phase 1 report, with recommendations for further investigations as required.
- A dissemination seminar will be held at the end of Phase 2.
Related WRc Work
- Best practice guidance and treatment models for GAC and oxidants for the removal of algal toxins from water supplies, EC DG Research and UKWIR, 1995.
- Laboratory and pilot scale studies investigating removal of organic micropollutants; including GAC batch adsorption and rapid column tests for pesticides, taste and odour compounds, and algal toxins, 1995-2006.
Duration: Phase 1: 3 months Phase 2: 6 months