Published on 30 January 2023
Soil remediation Yara successfully completed
In mid-2022, DCMR Milieudienst Rijnmond (DCMR) approved the latest evaluation report with the results of the soil remediation on the former industrial site of Yara Nederland in the Botlek. This signalled the successful completion of the soil remediation process.
Since February 2017, Witteveen+Bos has supervised the environmental aspects of the project on the site for this soil remediation project. This work was carried out under assignment to the contracting company Mourik Infra BV. The precise remediation location is known as 'D2'. Yara, an international manufacturer of fertilisers, had been using this location and wanted to return it to the Port of Rotterdam Authority. However, the location was contaminated with a degreasing agent during the business operations of another company.
As part of the return delivery, the contamination had to be remediated as required in the lease agreement. The variant study showed that source removal could be one of the possible approaches. In 2017, the source of the contamination – the zone with high concentrations of PER in the soil – was excavated to a depth of more than 5 metres in a sheet-pile pit and removed. Then in the period 2017-2022, Witteveen+Bos monitored the groundwater quality to assess whether the predicted decrease in concentration in the groundwater was proceeding as expected. The extinguishing effect of removing the source became clearly visible during this five-year monitoring period. The trend of the average concentration in the plume zone is also decreasing to below the legal intervention value. The competent authority was therefore able to agree with the remediation result that was achieved.