Kerdiffstown Landfill Remediation Project

This project involved the remediation of a former landfill site at Kerdiffstown, Naas, Co. Kildare by capping wastes, providing a landscaped profile across the site and improving the landfill infrastructure systems to ultimately provide a multi-use public park.

The site occupies approximately 30 hectares and the works include the installation of an engineered capping system across the site and the installation of new environmental management and control systems.

The specific objectives of the project were to:

• Reduce the environmental risk due to pollution by landfill gas, odour and leachate of the site to an acceptable level.
• Remove risks to public health and safety.
• Deliver a remediation solution which provides a benefit and is acceptable to the local community.
• Integrate sustainability and sustainable design and development in both the remediation works and the operation of the multi-use public park. 

Challenge

For over 20 years, Kerdiffstown Landfill had an adverse impact on the environment, local residents and the wider locality of Sallins and Naas, Co. Kildare. Odour issues, uncontrolled emissions of leachate and landfill gas, safety hazards (including a large landfill fire) and open waste bodies with associated issues of vermin and dust were commonplace.

We were appointed by Kildare County Councils as Employers Representative, PSDP and designer for the project, with full responsibility for the delivery of the detailed design, contract documents, contractor procurement, contract administration and construction supervision.

The remediation works at the Kerdiffstown site presented a number of significant environmental and planning implications for the project. Some of these challenges include the strict adherence to conditions of the Industrial Emissions Licence (P1063-01), as set out by the Environmental Protection Agency (EPA), as well as planning conditions issued by An Bord Pleanála.

During the construction works, it was important that we correctly manage emissions such as odour, landfill gas, leachate, noise, vibration, groundwater and the reprofiling of waste body across the site, which is needed to achieve the required levels and surfaces for the permanent landfill capping works.

The installation of wastewater and leachate transfer pipelines from the site to the nearest wastewater pumping station was a significant project task, which involved directional drilling under a live dual carriageway (N7) and the Morell River. It was also important to liaise regularly with the local residents and community to ensure that the works do not negatively impact them.

Solution

The full suite of services included in our commission were:

• Project management: reporting, schedule management, risk management, cost management, stakeholder management
• Procurement advice and services
• Health and safety: Project Supervisor Design Stage (PSDP) and designers’ roles
• Design: landfill engineering, civil, structural, geotechnical, mechanical and electrical, process, instrumentation, control and automation, architecture, landscape architecture
• Ensure all remediation design complies with the principles of sustainability
• Contract administration
• Construction monitoring

The construction and remediation phase included the reprofiling of the waste body which was deposited on an area in excess of 30ha. During the construction stage, management of emissions such as odour, noise, vibration and dust, in compliance with the EPA licence, was critical. We provided a team of Resident Engineers, to monitor all stages of construction.

Due to the proximity of neighbours and adjacent landowners, stakeholder engagement was an essential element of the services. It was crucial to the success of the project to liaise regularly with the nearest neighbours to the site and the local community to ensure that the works did not impact them in a negative way.

Throughout the project there was a focus on sustainability, initially addressed through the implementation of green procurement criteria and carbon tracking. Green procurement criteria were used at the tender stage, rewarding contractors who demonstrated sustainable solutions and set out a green strategy to deliver the project.

The carbon footprint of the remediation works which was established during the design phase and tracked monthly during construction was minimised by:

• Specifying reuse and recycling targets for key materials generated during the project.
• Sourcing suitable soils for use in the capping system within or close to the site.
• Maximising the reuse of crushed concrete materials through sustainable design of haul roads, trails, cycle paths and changing rooms.
• Recovering and re-using shredded tyres on-site to construct the all-weather astro pitches.