Bang Pakong Combined Cycle (Unit 1-2 Replacement) Project Technical Document Bufldin S Sink and Emergency Shower, eye and face wash g made of acid resistant material Water Treatment Plant I 1 ‘ 2A.l0 Coating and Painting Coating shall be applied to the exposed surface of all underground buried steel pipe, etc. as required. Painting shall be applied to all exposed surfaced of all buildings excluding Cooling Tower structures and firewalls of Transformers. Coating and painting for safety and protection shall be in accordance with building codes and regulations. See detail in Section7N Coating and Painting, Volume 2. Outdoor ladders, stairs, handrails, steel structures shall be hot-dip galvanized. Stainless steel material shall be used in high corrosion area affected by chemical substances. 2A.11 Cable Trenches, Duct Banks and Electrical Manholes Cable Trenches Cable trenches shall be provided to contain an adequate number of required cables, raceways and shall be covered with concrete slab. The drainage in cable trenches shall be slope designed to drain water to the plant drainage system via permanently installed automatic submersible pumps. Duct Banks and Electrical Manholes Duct banks shall be designed to contain an adequate number of ducts between the plant and outlaying buildings/structures and to protect the electrical cables from mechanical damage. All underground duct banks shall consist of plastic conduits with standard plastic spacers, placed at 1.5m intervals, encased in the steel reinforced concrete. The nominal diameter of the plastic conduit shall not less than 100 mm. Manholes shall be designed with respect to the duct bank size, location and orientation, extreme elevation change, or to tie in branches of the duct bank in which adequate for interior working space and associated cable bending radius limits. General straight runs, manholes spacing shall not exceed 100 m apart. Each manhole shall be provided with manhole cover, cable support, cable pulling eyes, bell ends, hot dip galvanized step ladder. The drainage in manholes shall be designed by providing sump pit at bottom slab, installing drainage pipe connecting between groups of sumps and finally routed to the lowest separately constructed stonn water sump pit. The collected water in the stonn water sump pit will then be automatically drained to the plant drainage system by permanently installed automatic submersible pumps. The seepage water shall not be collected in the manholes. 2A.12 Pipe Trenches Pipe trenches shall be designed and constructed to provide adequate space for containing all required pipes as well as maintenance purpose. Flexible connection shall be provided where pipe trenches connect to buildings or existing structures. Removable reinforced concrete slabs shall be provided in the intersection area between pipe trenches and road or in the area Where vehicles run pass. Routes shall be provided with suitable, appropriately Volume 2 Page 2A-35