When it comes to MMGW, we are told Science reigns supreme. When it comes to fracking, Science means nothing, it's up to Politics.
But I actually think politics, not science, should dictate outcomes, because the larger questions at stake with fracking are about values: How much risk is acceptable? How do we weigh competing goods? What is the proper place of humans in nature? In short, what kind of world do we want to live in and pass down to our children? These questions are not reducible to science. There is no scientific way to determine an optimal distance between fracking sites and playgrounds. That decision depends on how we want to balance the goals of safety, community character, and access to mineral rights.
So hard to keep the arguments of the Left straight.