Tasked with the complex remediation of a live industrial site in the Madrid province, our colleagues at Geostream Iberica had to ensure maximum efficiency with minimal disruption to workers.

Here’s how they did it:

The challenge

The site was contaminated with both chlorinated solvents – especially Trichloroethylene (TCE) – and petroleum hydrocarbons, which affected groundwater up to a depth of 16m.

These contaminants were present in two areas, including a canteen building and a laboratory building, about 50m apart, with a maximum concentration of TCE of 360 mg/l.

On top of this, local geology of silty sands interspersed with low permeability clay had caused groundwater to distribute into two discrete layers - shallow (4-5 m) and deep (12-16 m) – making access more difficult.

As the manufacturing site was operational, a noise emission constraint of 70dB was established, alongside air emissions and water discharge limits.

The solution

Geostream designed, installed and maintained two Multi-Phase Extraction systems, as well as carrying out extensive civil works to ensure minimal disruption to workers.

Vapours were treated with activated carbon, whereas water passed through several treatment stages including settlement tanks, cartridge filters and carbon filters.

Both plants were equipped with full remote access and with safety devices including bunded floors with level sensors, fixed in-line PIDs to monitor chlorinated VOCs, fixed ambient explosimeters and in-line pressure and temperature transmitters.

The team also designed and built a bespoke sampling kit, which allowed samples to be recovered under vacuum conditions while the plant was in operation.

Civil works took three weeks and consisted of: excavation of over 300m of ducted trenches, construction of 20 manholes, installation of underground pipework, and reinstatement of the trenches to match existing finishes within the canteen and laboratory buildings.

The result

The systems operated for nearly 100% of available time and complied with water, air and noise emission limits.

Remediation targets were achieved in 12 and 21 months respectively, ahead of the planned two-year schedule.

Looking for bespoke groundwater design and treatment solutions? Contact us on info@remediation.com to discuss your requirements.