The Texas-Louisiana border is home to a melange of 840 petrochemical, refining and power plants operated by some of the world’s largest companies... Most shut down safely before and during the storm, but the contamination they cast over the area existed long before Harvey dropped barrels of rain... [Due to Hurricane Harvey] the second largest oil refinery in the country... had a roof collapse and released pollutants into the air. Shell reported similar incidents due to heavy rains... [According to a local resident]... for the first time, some members of his family “were having trouble breathing and [getting] headaches” that lasted about two days at the height of the flooding... Environmental worries did not stop when Harvey’s record-breaking rains abated. “Our biggest concern is now that the flood water has receded is the flood water carried… a number of chemicals in the homes,” said Yvette Arellano, a researcher for Texas Environmental Justice Advocacy Services... Where water might have carried chemicals and metals since the neighborhood was inundated is unclear... “It’s usually a pretty complex mixture of chemicals that were already present in the environment and sewage and wildlife, like snakes,” said [an environmental scientist] about flood waters... “Doing environmental work in a place like Texas – where officials deny climate change is even happening – is extremely difficult. It’s a tough road, and they’ve been fighting this fight for a long time,” [a researcher for the Union of Concerned Scientists] said. “All I hope now is after this tragedy maybe people will start to listen, maybe they’ll take action”.