A multi-million pound distribution centre currently under construction near Kettering will process all its sewage waste on-site thanks to the innovation of Kingspan Klargester’s expert team of designers and engineers.
The distribution centre will cover 20 hectares and is due for completion in 2016. It will act as a central hub for major high street retailer Primark, and is expected to be staffed 24/7 by a workforce totalling 600.
While it is well located in terms of road networks, the centre has considerable topgraphical challenges and is some distance from services such as the main sewer – making the issue of waste disposal a major consideration for the project planners. Furthermore, the disposal of sewage effluent was made more complex by environmental sensitivities surrounding the local water course.
Eventually, having weighed up the options, it was decided that dealing with waste on-site would be preferable to an off-site solution primary because of the benefits the team felt this would bring.
To this end, the main building contractors, Sir Robert McAlpine, turned to Kingspan Klargester for specialist advice. Kingspan Klargester is not only the UK’s leading manufacturer of commercial off-mains drainage solutions, it also has an in-house team of specialist designers able to create bespoke solutions for any site/requirement and this project had a particularly tricky brief.
Chris Pike, Kingspan Klargester’s product manager, first arranged a site visit for a review to specify a private drainage solution.
Because the centre is positioned on slightly rising ground, the sewage treatment solution needs to be installed at depths of between three and six metres – making the consequent loading on the tank a concern. What’s more, the length and size of the site, along with the large number of staff, indicated that a substantial, bespoke treatment plant would be required.
The other issue is that the effluent from the treatment solution would discharge into a water course which flows through Sites of Special Scientific Interest (SSSIs) on its journey down to the River Nene. This means the quality of the effluent has to be very high which was reflected in the consent standard from the Environment Agency that was set at BOD;SS;NH3 of 20:30:10.
With all this in mind, the Kingspan Klargester team decided the Envirosafe commercial packaged sewage treatment plant was best suited for the installation.
Envirosafes are designed to deliver very high performance even in the most demanding and sensitive applications. In a standard configuration, it delivers total nitrogen consents (total N), Biological Oxygen Demand (BOD) levels of less than 20mg/l; suspended solids of 30mg/l; and Ammonia levels below 5mg/l. This means it outperforms most of the packaged systems currently on the market for nitrogen reduction and more than meets the consent standard set by the Environment Agency for such a sensitive site, both now and in the future.
Kingspan Klargester’s designers determined the correct size of the tank by referral to British Water’s Flows and Loads 4 Guidance. The Envirosafe is designed to be flexible and modular and the designers used this adaptability to create two linked tanks to achieve sufficient capacity and to effectively manage the collection, biological processing and disposal of the waste.
The weight of the soil at six metres could have damaged the fibreglass wall of the tank so the Kingspan Klargester engineers worked with Sir Robert McAlpine and TR Collier’s engineers to develop a concrete surround for the tank before the earth was backfilled around it.
The Envirosafe packaged treatment system is designed to simplify both servicing and maintenance and was supplied to the project with an extended 25 year warranty.
Roger Smart, Chief Engineer at Sir Robert McAlpine who is overseeing the installation advises: “The Envirosafe has ensured that future sewage waste is entirely self-contained within the site, minimising its environmental impact.
“What this has really proved to me is that engineers and landowners can feel confident about placing large commercial developments on land which is some distance from the main drain. Furthermore, the Envirosafe not only meets current environmental legislative requirements, it has the potential to go beyond them, future-proofing this development.”
Chris Pike advises: “This installation had many and very specific demands which we have been able to assess and meet thanks to both our expert designers and the flexibility and high performance afforded by the Envirosafe.
“It underlines the point that Kingspan Klargester is not simply a leading manufacturer of sewage treatment plants; we can offer the full package, including site surveys, design, warranty, service and maintenance for major commercial projects such as this.”
