In a memorable exchange from The Wizard of Oz, Dorothy tells the wizard how she and her comrades killed the Wicked Witch of the West.“We melted her,” says Dorothy.“Oh, you liquidated her, eh?” says the wizard. “Veeerry resourceful.”Veeerry indeed. Who knew that something as simple as a splash from a bucket of water would kill the witch and enable Dorothy and company to fulfill their quest and bring the wizard the broomstick?Wastewater treatment operators don’t often slay witches, but they do slay an incredible range of challenges with sometimes amazingly simple remedies. Only, unlike Dorothy, they don’t do it by
