Sustainability and Carbon Savings Achieved on the Kerdiffstown Landfill Remediation Project

𝐊𝐞𝐫𝐝𝐢𝐟𝐟𝐬𝐭𝐨𝐰𝐧 𝐏𝐚𝐫𝐤

Challenges

The Kerdiffstown Landfill Remediation Project aimed to remediate a large and complex landfill site while minimizing its environmental impact. One of the main challenges was managing the substantial carbon footprint associated with construction activities. The project team needed to identify strategies for carbon reduction from the outset, while balancing technical, logistical, and sustainability considerations. This required integrating sustainable practices throughout the project lifecycle, from planning and tendering to completion, to meet carbon reduction goals.

Impact

The project achieved a significant reduction in carbon emissions, delivering a 2.9% decrease compared to the initial baseline calculated during the tender stage. Originally, the carbon emissions were estimated at 10,970 tCO2e, but by the end of the project, emissions were reduced to 10,653 tCO2e, resulting in a total savings of 317 tCO2e. The carbon savings were achieved through the adoption of sustainable practices, innovative materials reuse, and the use of lower-emission fuels. The project not only demonstrated a successful approach to landfill remediation but also set a benchmark for integrating sustainability in large-scale construction projects.

Assessments

The carbon footprint was assessed and tracked using the Highways England carbon tool, starting at the tender stage. Monthly updates during construction allowed the team to monitor progress and identify additional opportunities for reducing emissions. This ongoing assessment ensured that carbon management was an integral part of project delivery.

Action Plan

Several targeted measures were implemented to achieve the carbon reduction goals:

1. Utilizing Site-Won Materials: A borrow pit was developed on-site to reduce the need for importing materials. Approximately 800 m³ of site-won materials, classified as 1S, were used as a free-draining sand layer under footpaths. This led to a reduction of 20 tCO2e, equivalent to eliminating 49 truck movements over 931 km.
2. Reusing Demolished Concrete: The project reused 11,396 m³ of crushed concrete from demolished walls as capping for access roads, resulting in a 290 tCO2e reduction. This action also prevented 946 truck movements, covering a potential transport distance of 18,000 km.
3. Recycling Rebar: During demolition, 885 tonnes of rebar were separated from the concrete and sent to a recycling facility, supporting resource conservation efforts.
4. Using Sustainable Products: Recycled rubber was incorporated into the rubber crumb for three all-weather pitches and wet pour surfacing for playgrounds and fitness equipment, reducing the need for virgin materials.
5. Recycling Tyres: Over 10,000 tyres used to weigh down a temporary liner were collected and sent for recycling. This diverted 240 tonnes of tyres from landfill and saved 2 tCO2e.
6. Trial of HVO Biofuel: The use of Hydrotreated Vegetable Oil (HVO) biofuel helped achieve an additional saving of 4.4 tCO2e, showcasing the potential benefits of lower-emission fuels in construction.

E-Learning Modules

The project incorporated e-learning modules to enhance team awareness and understanding of sustainable practices. These modules covered topics such as carbon reduction strategies, sustainable material sourcing, and waste management, equipping the workforce with the knowledge to actively participate in sustainability initiatives.

Value Gained and Future Proofing

The carbon savings achieved on the Kerdiffstown Landfill Remediation Project demonstrate the value of integrating sustainability into construction practices. The 2.9% reduction in carbon emissions not only contributed to environmental goals but also provided insights into effective carbon management strategies for future projects. The approaches used, such as material reuse, sustainable sourcing, and alternative fuels, set a precedent for ongoing improvements in carbon reduction.

The project’s successful implementation of a structured carbon management plan highlights the potential for future-proofing infrastructure projects through sustainable practices. By consistently applying these strategies, Wills Bros Engineering can enhance their sustainability credentials, meet regulatory requirements, and support broader environmental objectives. The learnings and processes developed during this project will serve as a model for achieving even greater carbon reductions in future endeavours.