Sampling was conducted on 28 days distributed between October 2005 and September 2006 covering all 12 months, and 4 weekly sampling campaigns. Some sampling events were conducted two or three times PTC124 day, resulting in a total of 68 samples. All samples were collected on weekdays. For monthly sampling, samples were collected once a month, on a Wednesday in the middle of the month. To determine the weekly fluctuation, sampling was conducted daily on Monday to Friday four times (once each in October 2005 and January, April, and July 2006). For each sampling event, samples were collected from seven sampling points (1, 3, 5, and 7–10 in Fig. 1) two (10:00 h and 16:00 h) or three times (10:00 h, 13:00 h, and 16:00 h) a chemotrophs day. For effluents ((10) in Fig. 1), samples were collected before the chlorination process. Wastewater samples were collected manually using a grab sampler and the average volume of each water sample was 1 L (2 L for effluent samples), whereas the average sludge sample was 10 g. The SS concentration was measured directly, and the influent water flow data obtained from the plant office was used to calculate the loading. Fig. 1 shows the setup of the wastewater.