There is a low roar under Chicopee Falls that most people stop hearing — the river going over the dam behind the brick mills, morning after morning. Back to Basics Lawn Care LLC works the streets above that sound, where front lawns run in short bright flights down toward the water. Mowing, edging, string trimming, mulch turned into the beds, leaves gathered when the maples finally let go: the list is plain, and the finish is not. A crisp edge along a Chicopee sidewalk holds its line all week, and holding that line is the entire point. Straightforward lawn care, carried all the way out to the corners, here and in the towns nearby.