Three months after a massive coal ash spill, the Tennessee Valley Authority (TVA) has begun dredging the ashen byproduct of coal-generated electricity from the Emory River using an Ellicott Series 370 "Dragon" dredge. Jacobs Engineering is the prime contractor for this first phase of the project. The Ellicott 370 “Dragon” began sucking up ash from the river April 2, TVA officials said during a news briefing. TVA's top environmental officer Anda Ray called the start of dredging…