A natural gas company drilling the lucrative Marcellus Shale formation released it's previously secret list of chemicals associated with the drilling process Thursday. Some praise the voluntary disclosure. But others say more information is needed. Michel Boufadel, professor of civil and environmental engineering at Temple, worries about the potential short-term impact of waste-water pollution. But he also says the long-term impact of the drilling process also needs to be studied. "For me in terms of public health and environmental impact, these confirm what we always felt that you have highly toxic material, you have hazardous material, and that's how you should treat that water, as if it’s highly toxic."