Thursday, April 16, 2009
Starting in January 2011, the state’s Department of Environmental Protection will impose a more strict policy regarding the total dissolved solid (TDS) content of industrial wastewater discharged in Pennsylvania. The dissolved solids are comprised mainly of chlorides (salt) and sulfates, which negatively affect the color, odor, and taste of drinking water. TDS can also be harmful to aquatic wildlife. Many of the solids in the water come from the drilling of new wells, where large amounts of water are used to fragment the ground. The Marcellus Shale wells in particular could use one to three million gallons of water during their drilling process; this water might then be burdened by the chloride and sulfate particles found naturally in the earth. DEP spokesman Tom Rathbun says in addition to the drilling of wells, TDS can come from a variety of sources. “Other sources are mining… industrial users of wastewater, and we also get a lot of TDS from runoff of parking lots and agriculture,” says Rathbun. The new limit for high-TDS water will be 500 milligrams per liter of TDS and 250 milligrams per liter of chlorides and sulfates. Visit the DEP’s website under the keyword "wastewater" for more information.