people building an underground sewer, with workers' suits, white helmets, low lighting, smooth sewer walls, a one-way sewer with an entrance at the end, an excavation in the ground straight in the middle where it is laid a pipe
people building an underground sewer, with workers' suits, white helmets, low lighting, smooth sewer walls, a one-way sewer with an entrance at the end, an excavation in the ground straight in the middle where it is laid a pipe