The following is a guest post from Christiana Z. Peppard, Ph.D, Assistant Professor of Theology & Science in the Department of Theology at Fordham University.

In the twenty-first century, the United States needs a bridge towards sustainability in fuel consumption.  The question is, what kind of bridge shall we build?

Regarding this question, natural gas extraction via horizontal hydraulic fracturing is a hot topic.  It is also a debate in which zealous rhetoric has swollen past the data.

The argument for hydraulic fracturing goes like this:  We need “bridge fuels” drawn from within our borders that will reduce our dependence on foreign fuels, stimulate job creation and economic growth, and pave the way for energy sovereignty in the coming century. Further, given the estimated enormity of geological shale formations in the United States—as in Pennsylvania, Ohio, and New York, for example—the technology of hydraulic fracturing is our next great hope.

Hope for what? The rhetoric is zealous. On June 25th, the Wall Street Journal decreed, “A new gusher of natural gas from shale has the potential to transform U.S. energy production—that is, unless politicians, greens and the industry mess it up.” More recently, David Brooks identified U.S. shale gas as a “blessing” but warned that, because of political polarization, “we groan to absorb even the most wondrous gifts.”

Now, I have a soft spot for religious rhetoric: I am, after all, a professor of theology and science. But, focusing as I do on human and environmental ecologies, I am also committed to good science and human wellbeing, especially as regards fresh water.

“We groan to absorb,” indeed.  Here is what I know about absorption.

Human bodies are permeable to external toxins. Our respiratory and gastrointestinal systems, as well as our skin, siphon the outside world in. Our fatty tissues are eager storehouses for synthetic chemicals from pesticides to plastics. (Toxicologists and ecologists provide striking evidence that such compounds persist in our bodies for decades, even the lifespan.) Many consumers have become concerned with contamination of fresh water supply.  Think, for example, of the anxiety produced by the news that excreted or discarded prescription medications travel through sanitation systems and return to the groundwater supply, potentially causing a range of poorly understood but disturbing outcomes. One known outcome, for example, is that male fish change gender when exposed to high levels of estrogen.

Hydraulic fracturing or “fracking” raises the biological stakes exponentially, and—more alarming—we do not know enough about what those stakes actually are.

Fracking is the injection of sand, water and chemicals, at high pressure and volume, deep into geological shale formations. Natural gas emerges from tiny pockets of rock substrate. This is what we know. But we do not know enough about the effects of this technology. The unknowns can hurt us—and might actually kill us. Proponents of fracking too often glide over those elements with glossy rhetoric.

Unknown One: What chemicals are in the fracking solutions? Gas companies know, but in most states don’t have to publicize the information. Yet an April report by the Minority Staff of the House of Representatives Committee on Energy and Commerce presented alarming data: between 2005 and 2009, gas companies actively used over 2500 different fracking solutions, 650 of which included “29 chemicals that are (1) known or possible human carcinogens, (2) regulated under Safe Drinking Water Act for their risks to human health, or (3) listed as hazardous pollutants under the Clean Air Act.” Yet these are chemicals in active use in fracking.

Unknown Two: Will toxic chemicals get into the water supply?  Gas interests, such as the American Petroleum Institute, insist that concrete “walls” can be built underground to keep synthetic solutions in place, or that the injections go deep enough so as not to be a threat to water supply, or that the fault for any seepage lies with rogue companies that fail to use technology appropriately.  But fresh water supply is a complex, dynamic reality at the intersection of hydrology and geology that cannot be assumed to follow humans’ rules.  As Robert Frost wrote: “Something there is that doesn’t love a wall.” In this case, it’s water and fracking solution.

One plus two equals Unknown Three:  Insofar as the possibility of watershed contamination with toxic or disruptive chemicals is real, not only is the integrity of fresh water sources at risk; so too are downstream effects on human health.  Companies insist that there is no evidence of negative impacts on human health.  What a tautology! Of course not:  For one thing, the chemical solutions have long remained undisclosed. For another, longitudinal studies of reliable size have, to date, been impossible.

Are these shale formations really the suggested Promised Land?  At best, they seem a mixed blessing

To be sure, the human virtues of ingenuity and technological innovation may eventually assuage such worries.  Fears may be proven wrong.  Corporations may not go “rogue.” Walls may contain water and toxic chemicals.   But the concerns are reasonable, and they may be proven right.  Who knows?

To thoughtfully examine reality is virtuous; to obfuscate it, vicious.  Only with more knowledge will we be able to decide whether, in the case of fracking, we are counting our blessings or squandering them.

Speaking of discernment: In the past ten years especially, the hierarchical magisterium has increasingly turned attention in Catholic Social Teaching (CST) to environmental issues.  Benedict XVI and the Pontifical Council for Justice and Peace have emphasized the importance of unbiased, scientific impact assessments for new technologies (see, for example, Caritas in veritate and the Compendium of the Social Doctrine of the Church, ch. 10).  CST of the past half-century has also steadily emphasized the inherent ambiguity of technology, most frequently vis-à-vis biomedical technologies, but also with regard to industrial economy and agriculture. The upshot: the creation of new technologies is a form of innovation that is proper to our powers as human beings; yet technology can be used for both good and bad purposes.  It can also lead to negative unintended consequences.

Thus, from my stance as a scholar of theology and science, environmental ethics, and CST, I can say that at least three steps are necessary before fracking can begin to be viewed as a desirable “bridge fuel.”

First, corporations must fully and publicly disclose what is in the mysterious fracking solutions.  Second, more independent research is needed into long-term ecological and toxicological consequences. Third, we must have clear and consistent regulatory structures at all levels of government to ensure that the health—downstream, upstream, and in-between—of American citizens will be valued and protected over and against the short-term profit sought by the legal “persons” known as corporations.

Science-based concerns about fracking and its attendant lack of transparency in an era of economic globalization are by no means the ravings of a radical fringe. Rather, they exemplify the virtue of prudence, which dates back at least to Plato and Aristotle and has an august history within moral theology. In risk-assessment circles, the virtue of prudence takes shape as the precautionary principle: Matters of this significance are not best decided by leaps of faith.  When there is doubt, desist.  CST has increasingly endorsed this principle of judgment and action.

By looking—hard—before we leap, we are more likely to achieve the human and ecological well-being that undergird any meaningful, long-term economic growth.  Otherwise, we may find ourselves building unstable bridges towards the Promised Land, only to discover that we have pursued a mirage.