Application: Treatment of contaminated yard runoff from a fertiliser packaging factory, Co Limerick. Spillage of fertiliser bags and dust residue is mixing with yard runoff. The result is a polluting nutrient-enriched effluent.
Consent: Not yet determined. This is a demonstration project to show how reed beds can be used to nitrify/denitrify and remove phosphate from runoff water. The final consent is likely to include standards for phosphates, nitrates and ammonia.
Solution: A hybrid system was designed and installed to demonstrate the nitrate/ammonia/phosphate removal process. Horizontal and downflow reed beds are used, together with chemical dosing to remove or break down pollutants, and to provide a carbon source for bacteria.
Results: This demonstration site is still being assessed. Nitrate removal rates are currently around 70%. A full treatment system will be designed during Summer 2007 for installation in 2008.