Nantycaws Landfill Site
Case Study: Nantycaws Landfill Site, Carmarthen, Wales.
Approximate Capitol Cost- £300,000. Volumetric consent to discharge 200mᵌ per day.
Achieved – 99.9% removal of NH4 at 80mg/l – Installation of major upgrades, consistent O+M results for 3 years.
The existing leachate treatment plant was failing to meet the consent levels and Carmarthenshire County Council were tankering on a daily basis. The council were looking for a robust treatment solution that would meet the consent requirements of National Resources Wales and reduce the level of tinkering.
JEMS was the (sub-contracted) project manager and site installer for WEBS Ltd, responsible for the build/installation of a new leachate treatment facility at Nantycaws Landfill site.
The previous plant consisted of a raw sump, a trickling filter, a large aerated lagoon (5000m³) and a reed-bed.
Consent To Discharge Limitations
- BOD: 20 mg/l
- TSS: 30 mg/l
- NH4-N: 4 mg/l
- Fe: 0.75 mg/l
JEMS installed the new treatment plant to include a 40m3 pre-aeration & settlement tank followed by three 40m3 moving bed bio reactor (MBBR) system with additional submerged aerated filter (SAF) and fine mesh rotary screen. The majority of the old plant was demolished. The lagoon is now being used for balancing of leachate volumes at the new plant. The reed-bed is redundant.
The system has proved successful on two counts: firstly, operating costs have reduced by 95% as tankering is now significantly reduced; secondly the effluent quality is well within the consent limits at <1mg/l BOD, 8mg/l SS, 0.074mg/l NH4N and 0.496 mg/l Fe. This resulted in a direct cash saving for the council of over 250k per annum.