By Kim Se-jeong
Seongdong District Office in Seoul said Tuesday that a ready-mixed concrete manufacturer has been leaking polluted water containing cement into the Han River and its tributaries.
The office said it is investigating to find out how long Sampyo Industries, which makes construction materials, has been dumping polluted water from its factory into the streams.
Test results by a city-run environmental institute showed that the discharged water contained calcium, silica, alumina and iron, key ingredients for cement. Cement is highly alkaline and is detrimental to the health of living organisms
The test also found the polluted water contained more suspended solids than permitted by regulations. While the amount of suspended solids permitted in waste water is 120 milligrams per liter, a water sample taken downstream from the plant was found to contain up to 506 milligrams.
A sample from Jungnang Stream nearby, where the water is discharged from the plant, had 96 milligrams per liter, which was within the permissible level, but it was still higher than the average.
“The average level of suspended solids in the stream is 16 milligrams per liter, but the test results were almost six times higher,” a district official said.
Sampyo’s plant is located near the Seoul Forest in eastern Seoul, close to a stream that flows into the Han River.
The leak was found on Oct. 27 after a resident reported an unusual color in the water in the stream.
A special investigation took place immediately and additional tests are ongoing. “After the final results come back, we’ll determine what to do with the company,” the official said.
The incident has triggered protests against the plant by district residents who have been calling for its relocation for years.
Last week, 800 residents gathered at the plant’s gate, demanding Sampyo stop releasing polluted water and come up with a detailed relocation plan.
Sampyo refused to comment, saying that it was waiting for the results of the investigation.