Houston's air is cleaner, but the goal post is moving
October 12, 2014 | Updated: October 12, 2014 8:23pm
![](https://webarchive.library.unt.edu/dentonfracking/20141029223246im_/http://ww1.hdnux.com/photos/32/52/66/6991260/4/784x2048.jpg)
October 12, 2014 | Updated: October 12, 2014 8:23pm
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