The Donor Site was the former Maliphant Railway Sidings Site in Swansea. The site is being redeveloped for the new Hitachi Trains Servicing Facility (part of the electrification project for the South Wales Main Line).
The main contractor, Volker Fitzpatrick Rail, identified the need to excavate 44,000 tonnes of contaminated and uncontaminated soils from the site as part of the overall development. Volker Fitzpatrick set an environmental target to divert 90% of the material requiring offsite disposal away from landfill.
The Treatment Hub was able to accept the material following a comprehensive review of the waste assessment commissioned by Volker Fitzpatrick Rail (carried out by ESG).
The hazardous / non-hazardous material (circa 16,000 tonnes) was shipped to The Treatment Hub with most of the remaining less contaminated soils being reused as engineering backfill on site. The bulk of the material (circa 14,000 tonnes) was shipped in an eight-week window between April and June 2014. A further 2,000 tonnes were shipped in December 2014.
The Receiver Site was a parcel distribution centre historically blighted by a diesel contamination leak. The contamination plume had spread extensively under the service yard and needed to be addressed from environmental and commercial perspectives.
The client’s environmental consultant had recommended the removal of the contaminated soils from the site and the replacement of these soils with a suitable geotechnical sub-base material.
Envirotreat contracted to carry out remediation works on the site on behalf of the main contractor, Chalcroft Construction, who were engaged by DHL to carry out site works.
It was decided that the most sustainable and economic remediation approach was to send the excavated soils to the Treatment Hub for subsequent treatment / recycling and to import treated recycled soils from the Hub for reuse on- site as sub-base material in the service yard reinstatement.
Reuse of Treated Material (Recycling)
The treated recycled soils originated from the Maliphant Sidings Site [the Donor Site].
The reuse of the treated / recycled material at the Receiver Site is shown below.
Earth Science Partnership [ESP] produced a Material Management Plan [MMP] for the proposed reuse of the recycled material as sub- base. The MMP was signed off by a Qualified Person [QP] in accordance with the requirements of the CL:AIRE Code of Practice.
The Treatment Hub was able to provide offer a sustainable and economic recycling solution. 6F2 material was transported to the site and utilised as sub-base resulting in a significant cost saving to the project.
A treatment strategy was proposed and implemented to achieve the required totals and leachate values (based on the chemical criteria / specification for the required sub-base material at the Receiver Site). The material was required to meet the criteria for the 6F2 Highway Specification – it was therefore necessary to crush and grade the treated material appropriately.
It was estimated that the Treatment Hub provided circa 1,500 tonnes of recycled material for use at the Receiver Site. It was necessary to demonstrate suitability for use and the specific requirement in terms of quantities.
The Treatment Hub enabled the recycling / reuse of material accepted from the Donor Site. The treatment / recycling process was fully compliant with the ‘End of Waste’ requirements enabling reuse of the material as a product in accordance with the designated specification.
The recycled materials were provided at a very attractive commercial rate.
The Treatment Hub was able to offer a sustainable and economic alternative to the use of virgin material.
The sustainable reuse of significant volumes / tonnages of soils resulted in Volker Fitzpatrick Rail being awarded the CIWM 2014 Award for Sustainable Construction and Demolition.