TSMC Kumamoto Plant Leaves Water Concerns

Kikuyo, Kumamoto Pref., Dec. 25 (Jiji Press)–While the local economy has been boosted by the full-scale launch of operations at Taiwan Semiconductor Manufacturing Co.’s first Japan plant a year ago, residents remain concerned about its impact on groundwater. The world’s largest contract chipmaker kicked off full-scale operations at the plant in Kikuyo, Kumamoto Prefecture, southwestern Japan, in December last year. Construction of the company’s second Japan plant, located next to the first plant, started in October this year for operations set to start at the end of 2027. The first plant pumps up to 7,500 tons of groundwater per day as it requires a large amount of water to clean wafers and others. Combined with the second plant, the amount of necessary water is expected to reach about 8 million tons a year. In November this year, Japan Advanced Semiconductor Manufacturing, a TSMC unit, held a press briefing to garner understanding on the chipmaker’s efforts on sustainable manufacturing activities at the 22,000-square-meter first plant. About 75 pct of up to 30,000 tons of water used at the plant per day is recycled water, according to JASM. The quality of wastewater totaling up to 5,500 tons per day is monitored around the clock under standards that are more stringent than legal regulations, JASM said. If an abnormality is detected, the system automatically halts and wastewater is treated again, it said. Through various efforts, such as filling rice fields with water in winter and letting such water seep deep into the ground, the plant recharged about 5 million tons of groundwater in 2024, equivalent to three times the amount of water used for the chip manufacturing operations, according to JASM. Some local residents, however, are concerned about possible groundwater contamination and depletion. The first plant uses per- and polyfluoroalkyl substances, or PFAS, which are not subject to regulations. Although wastewater from the plant is treated using activated carbon, it is still difficult to completely remove the “forever chemicals,” as such substances are known. Apparently referring to the Minamata disease, Koichi Ideta, a 70-year-old executive of a local civic group launched in February last year, said, “We’re concerned about the impact that PFAS-containing wastewater flowing into the Ariake Sea will have on people who eat fish and shellfish (caught in the sea).” The disease, whose first case was confirmed in the Kumamoto city of Minamata nearly 70 years ago, is a neurological disorder caused by the ingestion of fish and shellfish contaminated by industrial wastewater. Koichi Maeda, 78, who has been a rice farmer for about 60 years in Kikuyo said, “Even if (the TSMC side) says that the water is clean, I would not drink it.” While voicing understanding for positive effects on the local economy from the plant, he called on TSMC and the Kumamoto prefectural government to provide a “sincere” explanation about their outlook on the groundwater situation. Since August 2023, the prefectural government has been conducting water quality tests at an outfall of a facility treating wastewater from the TSMC plant and at a river. While there has been a temporary increase in PFAS levels, they were still well below the targets set for drinking water in the United States and Germany, according to the prefecture. Such levels have since decreased and currently remain unchanged. “We’ll strive to work together with authorities and our suppliers to reduce the impact on people’s health and the environment,” a JASM official said. Kumamoto Governor Takashi Kimura said, “Our prefecture’s rich groundwater is an important asset,” adding, “We’ll work hard to preserve the quantity and quality of groundwater to ease concerns among local residents.” END [Copyright The Jiji Press, Ltd.]