SMR Applications: In-Situ Stabilisation
Where: Middlewich
Background
This project involved the construction of a temporary haul road capable of withstanding the weight of HGV vehicles and heavy plant at the Holford Gas Storage Project near Middlewich for E.ON UK and Jacobs Engineering.
Problem
The existing ground area within the brine fields was thick clay and slurry with no adequate drainage. The ground underneath was also mostly salt and minerals left from oceans that had evaporated millions of years ago. This means that water just settles making the ground conditions as poor as it could possibly get.
E.ON UK needed a practical solution that would not exceed the budget and would work where other solutions would fail. Impacts on the environment, local wildlife and residents also had to be taken into consideration when making any decisions on what option would be best.
Heavy plant would cause further disruption to local residents, as well as increase the Company’s Carbon Footprint. The area is also the habitat of many protected species including the Great Crested Newt so it was paramount that all works could easily accommodate the necessary measures to prevent disruption or contamination of any of the many ponds.
Solution
Recycling Aggregates Northwest (RAN) were chosen by E.ON as they could use its mobile recycling facilities and SMR product to overcome all the impending problems and work within the budget. Further costs where also saved by not having to pay heavy freight and ever increasing landfill charges.
The existing clay could be excavated and recycled to construct a temporary road to the required specification. This also meant that the disruption to local residents, wildlife, and environmental impact were also minimised.
To construct the temporary haul road, the existing clay had to be levelled off and excavated 500mm to the formation level. The clay was then treated with SMR and relayed and compacted in two layers of 250mm (500mm in total). The results were astonishing; particularly as the general ground conditions where so poor. A solid road was constructed using only the existing clay, slurry, and SMR.
Once completed the road more than successfully provided the desired access for heavy vehicles and remained almost unscathed throughout its use only succumbing to minimal damage despite heavy use by lorries and excavator; often turning within a tight turning circle.
Benefits
Whilst this is not a ‘traditional’ project for the SMR based reinstatement solution, it is a perfect example of how a workable solution can be delivered with a lateral approach and delivering all the desired benefits that included:
Cost effective solution: Whilst other temporary road solutions were available these were not only incredibly expensive to transport to site and deploy, but would have taken longer to deploy and had a much greater and longer environmental impact on the surrounding ecology.Speed of deployment: By using what was on site and not having to bring in any additional materials the road was constructed extremely quickly, within the tight budget, providing the required site access and meant that now delays were incurred on the wider E.ON project.
No additional materials required: A solid useable temporary road was constructed using only the existing clay, slurry, and SMR that met all requirements.
Ecology compliant: Despite the surrounding land being really waterlogged, construct the temporary haul road using an SMR based sub-base helped protect the local environment.
