Verification of Automatic Water Sampling System for Chemical Spill Events

An applicability evaluation was performed for an automatic sampling strategy to respond to chemical accidents and the method was compared with manual grab sampling. The auto sampling includes a deep-well pump and an auto reverse filtration system, which resulted in up to a maximum of 6h of running time. Sampling was carried out at three locations on May 22 and June 20, 2019 and pH, dissolved oxygen (DO), and temperature were measured on site. In addition, samples collected via the two methods were analyzed for BTEX (benzene, toluene, ethylbenzene and xylene), three elements (Fe, Mn and Zn) and microorganic pollutants. BTEX was not detected at all at the sites and the concentration ranges were 5.0 to16.0 μg/L for Fe, 0.9 to 65.0 μg/L for Mn, and N.D. to 24.0 μg/L for Zn. Target screening was performed for 15 micro organic pollutants including pharmaceuticals and pesticides and for the 12 compounds that were quantitatively analyzed, the concentration range was N.D. to 55.0 ng/L. We measured the concentrations and the values for the two sampling methods were compared, resulting in 14 out of 17 samples showing good agreement between the two methods. As a result, this automatic sampling method is expected to be applied in various fields (e.g., mobile analysis system).