Soil and Groundwater Purification

Toshiba Group studies the situation of soil and groundwater contamination at production sites and implements purification measures. We also implement safety measures for environmental equipment in order to prevent contamination and to reduce the risks posed by chemical substances. We conducted a simultaneous study of all sites and found contamination at 12 sites. At the contaminated sites, purification of contamination by volatile organic compounds (VOCs) is underway, and we are monitoring the contamination level. VOCs in groundwater are collected and removed primarily by the water pumping method.

We focus on high VOC concentration areas for purification by water pumping. As purification progresses and the VOC concentration falls in these areas, we shift more intensive pumping to areas with relatively high VOC concentrations. In FY2021, we collected 223.9 kg of VOCs. This is a decrease of about 25% from the previous fiscal year, which can be attributed to the drastic purification measures implemented during land development, the shift from pumping to in-situ purification, and the gradual decrease in VOC concentration (i.e., VOC retrieval) due to previous purification efforts.

We will continue to implement soil and groundwater purification measures using methods appropriate for the laws, regulations, and the state of development of purification technology. Meanwhile, we will proactively communicate with local governments and communities by, for example holding purification facility tours.

*1 Purification method:
(A) groundwater pumping, (B) soil gas suction, (C) reduction decomposition, (D) oxidation decomposition, (E) interception containment, (F) removal by excavating soil, and (G) bio-activation.
*2 Amount collected:
Amount collected from April 2021 to March 2022
*3 Monitoring of the contamination level after engineering work to remove contamination or the purification procedure is complete.