■Does the handling change if it contains harmful substances? If sludge leaches heavy metals or PCBs beyond certain standards, it becomes specially controlled industrial waste. However, the sludge in question is limited to specific facilities that generate it. At the applicable business sites, a management officer for specially controlled industrial waste is appointed for each facility. The relevant facilities are specified by the Waste Management Law's ordinance. ■Determination is based on the amount leached, not the amount contained! The unit of the determination criteria is mg/L. It is assessed based on the amount leached into water, not the amount contained in the sludge. According to the method specified in the notification, the sludge is mixed with water, stirred for 6 hours at room temperature and pressure, and then the filtered liquid is measured. ■Examples of landfill disposal standards Examples of standards for landfill disposal are as follows: 1. Lead: 0.3 mg/L 2. Cadmium: 0.09 mg/L 3. Mercury: 0.005 mg/L ■Is one contractor sufficient? Article 12 of the Waste Management Law stipulates that transportation must be entrusted to a collection and transportation contractor, and disposal must be entrusted to a disposal contractor. When handing over, a management ticket (manifest) must be issued, and a copy must be kept for five years. Even if transportation and disposal are entrusted to the same company, each respective permit must be verified.

■There are standards for storage until transportation According to the Waste Management Law, industrial waste must be stored in accordance with the storage standards to ensure that it does not hinder the preservation of the living environment until it is transported. Article 8 of the enforcement regulations of the law stipulates that a fence must be established around the storage location and a signboard of at least 60 cm in both width and height must be placed. If there is a risk of wastewater, a drainage system must be installed, and the bottom surface must be covered with materials that do not allow water to seep through. This is particularly important to confirm in the case of sludge with high moisture content. ■Things the person in charge should first confirm 1. Source: From which facility or process the sludge originated 2. Leaching test: Whether it meets the criteria for specially controlled industrial waste 3. Permit: Whether the contractor has the permit for the collection, transportation, and disposal of sludge 4. Management ticket: Whether the issuance and copies are stored for five years ■What to do if you are concerned about disposal costs? The amount of sludge and its moisture content can vary depending on the type and amount of coagulant used, as well as the condition of the dewatering machine. There are methods to review not only the disposal stage but also the operating conditions of wastewater treatment. Torii accepts consultations regarding chemicals for wastewater treatment and inspections of wastewater treatment facilities. Please feel free to consult with us first.