HORTON 2011 CAPPING
Horton Landfill Site, in the South Downs area of West Sussex, was a former clay pit supplying a nearby cement works. The site had been used as a landfill for many years, and landfilling was completed in the summer of 2011. Peter Baxter Associates have been involved with this site for many years. The final phase of capping and gas infrastructure was constructed between August and December 2011, and comprised over 62,000m2 of 1m clay cap, formed largely from imported clay, with 44 new gas wells and associated collection pipework.
Peter Baxter Associates were retained by the operator, Viridor Waste Management, as CQA Consultant. PBA maintained a full time CQA Engineer on site, who also carried out nearly 300 density core tests on the compacted clay in an on site laboratory. This field testing regime was specified in the CQA Plan prepared by PBA, accepted by the Environment Agency, and provided cost savings to the client along with better CQA control. Check samples, and other parameters, were tested in PBA’s UKAS laboratory.
PBA also prepared the tender documents and acted as the Project Manager and CDM coordinator.
Gas well drilling
Kemsley DS Smith Ltd, a major locally based paper manufacturer, maintain a closed landfill at their works in Kemsley, Kent. Peter Baxter Associates Ltd were asked to develop a geotechnical design solution for an area of subsided clay cap.
PBA carried out a site investigation, development, CQA Plan, verified the suitability of the proposed imported clay used in the repair, provided CQA supervision and reporting, and carried out compliance testing for the repair.
Compaction in Progress
For this 3.8 ha geomembrane capping project at Margetts Pit, Burham, Kent, Peter Baxter Associates Ltd carried out detail design, prepared and agreed a CQA Plan and provided visiting and full time CQA Supervision, as well as compliance testing during the construction period.