Careys Civil Engineering was appointed principal contractor for the ground and enabling works packages on the Watford Riverwell project. This development in Watford will create 670 new homes in five residential blocks and will provide landscaped areas, open to the public.
On this project, we significantly increased reusable volumes of excavated spoil by careful remediation. Also, as part of our remediation and sustainability strategy, we imported “clean cover” materials under CL:AIRE – Leading sustainable land reuse protocol from another nearby Careys’ project.
Identifying further contamination
After being awarded the contract, we conducted a significant amount of additional site investigation in order to further inform the client’s draft remediation strategy. This site investigation included digging trial holes on a 10m grid and installing new monitoring wells. Within three days, our in-house soil lab returned detailed results identifying hotspots. This information enabled us to confirm the remediation strategy required for the individual waste streams and to deploy our soil remediation mobile plant licence in agreement with the Environment Agency.
Implementing an effective and efficient strategy
In order to overcome the challenges presented by the need to remediate the significant amount of additional spoil – such as potential delays and extra costs – our remediation manager and environmental consultant, AAe, devised a mitigation method. This included bio-piling, asbestos picking, screening/crushing and segregation under a watching brief.
In addition, one of our most important and effective remediation tools on this project was our in-house lab and soil engineering plant. This state-of-the-art plant forms part of our self-delivery model, which gives us the ability to offer a wide variety of construction solutions. It enables us to carry out sustainable cleaning and reuse of soil without the need to engage costly and time-consuming third-party services.
Sustainable soil washing plant
At Watford Riverwell, our soil washing plant allowed us to process up to 750 tonnes of earth each day, separating aggregates of different sizes from the soil in preparation for possible reuse. Use of this soil engineering plant significantly contributed to our impressive delivery time. Approximately 20,000m3 of soil was processed by our soil engineering plant.
To read more about our soil engineering plant please click here.