15 of 74  Construction of Giresun Wastewater Treatment Plant  Tender Dossier Volume 3 Employer’s Requirements  Section 3: Plant Description  Coarse screen channels shall be designed, constructed and equipped regarding the requirement set in  Table 2-1. The maximum flow (Q$_{WW,h}$) of the related stage requirements shall be met for the unit. There shall be electrically actuated motor controlled penstocks in accordance with the specifications  given in Section 7.8.8 and 7.8.18 at the inlet and outlet of coarse screen channels in the scope of  project. The operation status of the penstocks should be monitored and controlled by the SCADA  system. The screens shall be made from stainless steel 1.4404 in order to prevent corrosion.  The cleaning mechanisms of the coarse screens shall be automatically operated by water level sensors  (ultrasonic level or radar type sensor) located upstream and downstream of the screens (level  difference). In addition to this, the cleaning mechanisms for the coarse screens shall be operated by  time intervals. Time intervals must be adjustable from the SCADA. Coarse screenings shall be  transferred via conveyor and automatically disposed to a container on ground level. The coarse screens, with their screenings containers, shall be located in a building with frost-free  conditions. The requirements for the drainage, foul air collection and clean water supply system stated  in Section 3.3.4.34 and 3.3.4.35 should be met for the building inner area. The coarse screens shall be locally controlled and operated as autonomous units. The operation status,  however, shall be monitored and controlled by the SCADA system. Furthermore, water levels in front  of and behind the coarse screens should be monitored from SCADA.  Details of the coarse screens are:  Coarse screens: 3.3.4.3 Inlet Pumping Station  3_Vol3_d4.3_Section 3_Plant Description_GIR_rev08  Inlet pumping station shall be designed, constructed and equipped regarding the requirement set in  Table 2-1. The maximum flow (Q$_{WW,h}$) of the related stage requirements shall be met for the unit. In the architectural design of the pumping station, the distance between each pump must be greater  than 0.5 meters.  After passing the coarse screen channel, the wastewater shall be lifted by the inlet pumps to a level  that will allow gravitational flow through the rest of the wastewater treatment plant. The requirements  for the drainage, foul air collection and clean water supply system stated in Section 3.3.4.34 and  3.3.4.35 should be met for the inlet pumping station inner area.  Minimum number of coarse screen channel for Stage 2  : 3 channels + 1 spare channel (with all  equipped)  Maximum bar aperture  : 20 mm  Type  : automatic screen  Maximum velocity through bars at maximum flow  : 1.2 m/s (in the case of 30% clogging)  Minimum storage capacity and type container  : in accordance with 7.8.29.  Minimum number of the containers  : 3 items 