Polypipe Rigidrain applied at Namoya tailings facility

A highly effective solution for sub-soil drainage from Polypipe is now in operation at the tailings management facility of the Namoya gold mining project in the DRC.The Namoya mine, situated at the south-western end of the Twangiza-Namoya gold belt,covers an area of 174 km² and is expected to double the company’s projected gold production to more than 225,000 oz/y. Gold was first discovered in the area in 1930 with various mining operations subsequently taking place.

The Namoya site houses a substantial tailings management facility. Following a competitive tender, the Ridgidrain twinwall drainage system from Polypipe, the UK-based manufacturer of water management and plastic piping systems, was selected to provide effective sub-soil drainage. Ridgidrain is described as ideal for non-pressurised sub-surface drainage applications, with perforations at regular intervals along its full lengthto allow safe and gradual drainage. Manufactured in high-density polyethylene (HDPE), Ridgidrain has “excellent abrasion resistance both internally and externally – protecting against both sediment within the wastewater and the rugged mine environment.” It also offers a high compression strength to withstand imposed loadings, yet is still incredibly lightweight for ease of installation and transport.

The Ridgidrain system allows for the controlled seepage of treated water. The system can also deal with unpredictable fluctuations due to factors including stormwater and is a crucial element of an effective water management system. Polypipe supplied 1,386 m of 500 mm diameter and 190 m of 600mm diameter of its Ridgidrain twinwall pipe, shipped via eight 40 ft ocean containers,which required close co-ordination between Polypipe’s UK manufacturing operation and the shipping agent in order to meet deadlines and ensure the full order was dispatched as one shipment.

Polypipe Export Sales Manager Philip Wood adds: “Plastic piping systems such as Ridgidrain are up to 94% lighter than concrete alternatives, meaning that they are safer to install and move around site, and also offer considerable environmental benefits. Production and transportation are simplified and use less carbon, and additionally the product can often be re-used elsewhere when the project ends. These factors are key considerations for mine operators, and also make the product more cost effective. For these reasons, Ridgidrain is growing in popularity in the African mining market.”