Choo Mi-ae Calls for Stricter Semiconductor Wastewater Quality Control... Requests Standards for Chloride and Sulfate Ions

Governor Choo Mi-ae of Gyeonggi Province has emphasized the need to strengthen not only the management of water volume but also water quality control in semiconductor industrial complexes. This comes after concentrations of chloride and sulfate ions in Jukdang Stream, where treated water from SK hynix in Icheon is discharged, were found to exceed the irrigation water guidelines recommended by the Food and Agriculture Organization (FAO) of the United Nations. Gyeonggi Province plans to request the central government to establish related standards and will also require companies to come up with measures to improve water quality.

On October 6, Governor Choo stated on her social media, "Managing the quality of wastewater from semiconductor industrial complexes is absolutely essential, not just the volume." She added, "While the first administrative guidance was directed at water quantity, this time I am raising concerns about water quality."

Previously, Governor Choo asked Samsung Electronics and SK hynix—both set to establish operations in Yongin—to increase the recycling rate of process water and to reduce the amount of wastewater discharged.

The Gyeonggi Institute of Health and Environment conducted a water quality assessment of Jukdang Stream near the SK hynix semiconductor plant in Icheon, where similar processes are in operation, in order to predict the future impact of process water from the SK hynix facility in Yongin on the Gosam Reservoir in Anseong. Three inspections, carried out on August 26, September 2, and September 3, confirmed that all nine river water quality indicators regulated domestically were within the respective standards.

Gyeonggi Province Governor Choo Mi-ae's post on her SNS on the 6th

The issue involves chloride and sulfate ions, for which there are currently no domestic river water quality standards. At a point 0.4 kilometers from the SK hynix discharge outlet, the average concentration of chloride ions was measured at 731 mg/L and sulfate ions at 1,561 mg/L. Even downstream, 7.4 kilometers away, chloride and sulfate ions were detected at 513 mg/L and 1,060 mg/L, respectively.

These levels exceed the FAO’s chloride ion guideline of 355 mg/L and the typical sulfate ion range of 0-960 mg/L used in irrigation water assessments. However, based on the findings of this investigation alone, it is not possible to conclude that there will be crop damage or deterioration of water quality in Gosam Reservoir. A dilution effect was also observed, with concentrations decreasing further downstream.

Governor Choo is particularly concerned that process water generated at the Yongin semiconductor cluster will flow not into a river but into Gosam Reservoir, which is a freshwater body used for agricultural purposes.

Gyeonggi Province believes that management standards to protect agricultural water are needed in situations where large quantities of process water are discharged into agricultural rivers and reservoirs. Accordingly, the province intends to ask the central government to establish separate permissible discharge standards for chloride and sulfate ions and to press related companies to reduce process water discharge and develop measures to improve water quality.

This content was produced with the assistance of AI translation services.