A Kaohsiung official collects samples at the location, where ASE's wastewater pipes enter the river.
Taipei, Dec. 10 (CNA) A case involving Advanced Semiconductor Engineering Inc.'s (ASE) discharge of toxic wastewater into an irrigation stream in Kaohsiung was been referred to the Kaohsiung District Prosecutors Office on Tuesday.
The city's Environmental Protection Bureau took the case to district prosecutors on suspicion that an ASE factory in the southern city's Nanzih District was intentionally releasing untreated wastewater into Hojing Creek.
The factory's alleged action "put public health at risk" because the water in the river is used for irrigation purposes downstream, the bureau said.
The plant, called K7, releases around 5,000 tons of wastewater daily, the ninth largest volume discharged from factories in Kaohsiung.
The water from the K7 plant empties into Houjing Creek, which runs through more than 900 hectares of mainly paddy fields.
The city's environmental bureau said K7 releases wastewater around the clock and that samples of the water were found to contain metallic nickel at a hazardous level of 4.38 mg per liter, way above the allowable level of 1 mg/L.
This indicates that "the wastewater was being released without treatment," said an investigator at the bureau.
The incident resulted from damage to K7's wastewater treatment facility, which caused a leak of hydrochloric acid, investigators found.
The plant should have informed the relevant authorities and taken emergency action immediately after it detected the problem, but it failed to do so, the bureau said.
Instead, the plant attempted to deceive officials by running tap water into its wastewater storage pool when samples were to be taken for regular testing, the bureau said.
Earlier in the day, the city bureau slapped a fine of NT$600,000 (US$20,314) on ASE, one of the world's leading providers of semiconductor packing services, and ordered it to suspend K7's operation, but no time period was mentioned.
Meanwhile, ASE chief operating officer Tien Wu apologized over the incident and promised to take corrective measures.
"I hope the negative glitch will raise positive environmental consciousness and serve as an attempt to seek progress," he said at a press conference late Tuesday
In an apologetic letter to company employees that was read at the news conference, Wu admitted that the hydrochloric acid leak at the plant on Oct. 1 had been mismanaged.
The K7 plant employees around 5,000 workers and generates a monthly revenue of some US$75 million, over 30 percent of ASE Kaohsiung's total revenue per month, according to the ASE group.
ASE Kaohsiung, the group's flagship company, accounts for about 28 percent of the group's total revenue.
(By Chen Chao-fu, Jalen Chung and Elizabeth Hsu)