(November 6, 2017, 12:37 PM EST) -- PITTSBURGH — Glass manufacturer PPG Industries Inc. on Oct. 16 filed a brief in a Pennsylvania federal court, contending that “several of the Plaintiffs’ purported material facts consist of inadmissible speculation” in relation to groundwater contamination claims that environmental groups have brought against the company (PennEnvironment, et al. v. PPG Industries Inc., et al., No. 12-342, W.D. Pa.)....