Environmental Site Investigations and Remediation for Bosch Sites in Japan

After CDM Smith had already been entrusted with extensive site inves­ti­ga­tions for several cont­a­m­i­nants of concern at the former Robert Bosch Japan Higashimat­suyama 2 site from 2012-2017, Robert Bosch GmbH commis­sioned CDM Smith in 2018 to carry out soil and groundwater remediation of site areas impacted with chlorinated hydro­car­bons and hexavalent chromium.  

Remedial tasks at the Higashimat­suyama 2 site in­cluded soil excavation of hexavalent chromium impacted soil via over drillings using large diameter (2-meter) augers, dechlo­ri­na­tion of VOC impacted areas via groundwater injection of bios­tim­u­lants, instal­la­tion of upgradient zero-valent iron reactive barriers, and in-situ reduction of hexavalent chromium to non-toxic trivalent chromium in some site perimeter areas via injection of a mixture of ferrous sulphate and molasses. This process, fairly common at CDM Smith remediation sites in the USA, is unusual in Japan and presented the best approach to the technical challenges associated with overhead powerlines, nearby housing, and an adjacent public street. A planned second in-situ treatment was not necessary, as CDM Smith supported Bosch in the Purchase and Sale Agreement nego­ti­a­tions for the property and thus reached an agreement with the buyer to assume the residual risk of the immobilized areas.

For three chlorinated hydrocarbon source areas, CDM Smith conducted limited soil excavation in near surface areas and in-situ anaerobic degradation for the remaining source areas.

The former Bosch site Higashimatsuyama 2 site was sold in April 2018 and until 2020 a Shopping mall was constructed and completed by the new owner. The 2-year groundwater monitoring, as requested by Japanese regulatory authorities, was executed in parallel to the construction activities and finalized in March 2021 with no exceedance of any official remediation threshold. In June 2021, the Japanese regulatory authorities removed the site from the official contaminated land cadaster. With the successful completion of the remediation prior to selling the property, CDM Smith generated value added for Bosch, since the selling price exceeded the remediation costs by far.