Chapter 3: Digging into Digestate Every day, Washington DC’s Blue Plains Advanced Wastewater Treatment Plant receives 300 million gallons of wastewater from the nation’s capital.105 Little of this wastewater is wasted. The plant, situated on the shores of the Potomac, uses gas byproducts such as methane from AD for heat and power. The Blue Plains plant also notably disinfects biosolids—called digestate—for use as fertilizer. Blue Plains produces high-quality fertilizer from its sludge labeled by the U.S. EPA as a Class A EQ biosolid, a designation that allows for commercial sale. DC Water now sells its fertilizer in DC, Pennsylvania, Maryland and Virginia as Bloom. Its customers include landscapers, farmers, homeowners, and even the National Park Service uses Bloom as fertilizer on the National Mall.106 DC Water sells Bloom in bulk and in stores and generates a source of profit from D.C.’s wastewater. Chinese wastewater treatment plants have not yet begun to tap the market of producing and selling digestate.
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