Colin Conway’s 509 series of novels, about police work in the Spokane, Washington area, is a consistently interesting and satisfying shelf of books with a revolving cast of characters. The Tipping Floor stars city detectives Quinn Delaney and Marcy Burkett, coordinating with sheriff’s detective Heather Newberry.

A group of elementary school students are touring the city’s Waste to Energy Processing Facility, when they notice a human leg dropping from the jaws of an excavating machine over the “tipping floor” where trash is separated for recycling or incineration. Work stops abruptly, and procedures and schedules get tangled as the whole waste management operation gets shut down so that firefighters can search through a mountain of rotting waste for the rest of the body.

The victim is soon identified as a woman who has been missing for a week, last seen jogging. The husband is the natural suspect, but not only does he have a good alibi, he seems genuinely distressed for her sake. As the search for body parts goes on, the investigators try to piece together the world of a woman who seems to have been unusually secretive.

As always in Conway’s books, the detectives and their routine are described in detail. A lot of the story is viewed through the eyes of Heather Newberry, who is a lesbian. About all I can say about that is that she had less of a chip on her shoulder than one might expect.

The Tipping Floor was not my favorite 509 book, but it was well written and rewarding.