Project: M74 Extension, Glasgow
Timescale: 8 months
ERS was appointed to remediate soils contaminated with chromium ore processing residue (COPR) which was otherwise destined for landfill. Working in conjunction with the client and SEPA, a stabilisation and re-use strategy was agreed to treat the chromium VI leachability whilst reducing the project’s embankment material deficit.
We started with treatability studies at our laboratory in Glasgow to determine the best mixture of soil stabilisation reagents to reduce the leachability of hexavalent chromium and other contaminants to acceptable levels. Targets were also set for geotechnical properties to permit suitable soils to be re-used as a construction material.
After successful negotiations with SEPA, we set up an on-site soil treatment centre and mobilised our state-of-the art soil stabilisation equipment to treat the COPR contamination. We also created an on-site testing facility to allow immediate remediation validation and material re-use, saving the client time on waiting for external laboratory results.
The soil treatment centre was fenced off and access to the work area was through a decontamination unit. All personnel accessing the site had to wear the specified PPE. Extensive dust monitoring exercises were also carried out throughout the project, ensuring site personnel and nearby residents were not harmed.
In total, 100,000 tonnes of material was successfully treated and stabilised, with material quality actually exceeding leachability targets. The soil was then re-used on site as fill material for embankments, saving the client £4,000,000 on landfill and procurement costs.