Dover's older streets were laid out on the hillside, which means driveways that pitch straight down to the road and freeze into a sheet. J & J Construction and Landscaping works those in winter: plowing, clearing walkways, shoveling stairs and stoops, spreading salt where the grade turns treacherous. On a slope, where the snow gets pushed matters as much as how fast it moves — leave a bank in the wrong place and the melt comes back as ice. When the storm ends near sunrise and the whole hill is open and dark-paved, that's a finished night. The trucks head home and the borough goes to work.