Lynemouth - Design, Manufacture and Installation of Lagoon Baffles

The Employer requires a pair of bespoke baffles to be designed, manufactured and installed in a lagoon located at Lynemouth Mine Water Treatment Scheme. The Lynemouth Phase I mine water treatment scheme (MWTS) is located on the Northumberland coast on the site of the former Ellington Colliery. Coal mine water is abstracted at a rate of circa. 115 L/s from an abandoned mine shaft, treated through two lagoons configured in series before being discharged into the sea. The lagoons are constructed in colliery spoil and lined with an HDPE liner. The treatment process is designed to reduce total iron in the effluent which presents as ochre sludge in the lagoons; the mine water is currently subject to peroxide dosing. Lagoons are taken off line periodically (24 month intervals) to remove sludge by means of pumping. The site is in a remote location there being no permanent welfare facilities on the site. The employer intends to install two baffles in lagoon No 1 in order to optimise: • mean residence time; • longitudinal mixing characteristics; • reaction and settlement of ochre within the lagoon.