Arvada's lots go empty around nine at night — the shopping center on Wadsworth, the office park off Indiana — and that is when the snow gets handled. ION Snow Services runs the dark hours. Plowing lots and lanes, stacking piles where they will not block sight lines, shoveling entries and walkways, spreading ice melt so the first shift at six finds bare pavement. Under sodium light, falling snow looks like it is going up. By sunrise there is nothing to see, which is exactly how it should read.