Half of southwest Denver's snow ends up in the alleys, and D J's Snowplowing & Maintenance Inc knows those alleys the way other people know street names. Come January the powder here falls dry and weightless off the mountains, then piles against garage doors from Athmar Park to the banks of Sanderson Gulch until somebody moves it. Plow the lot, open the drive, cut a clean path from the door to the curb, then salt the north-facing runs where the sun never reaches all winter. Snow handled early stays easy; snow left alone turns to rutted ice by midweek. They would rather work at midnight than let a property get there.