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It can be called hydraulic fracturing, hydrofracking, or simply fracking. But by any name, the energy-gathering process is a controversial topic that has drawn passionate debates over its safety and usefulness.聽

To Stephen Tajc, Ph.D., however, fracking is not so much a controversy as a scientific puzzle involving one small molecule and billions of gallons of water. The solution to the puzzle鈥攆ollowing many, many more lab hours still to come鈥攃ould resolve a major ecological problem associated with this contentious modern issue.

As is the case with many scientific breakthroughs, this one was revealed through a convergence of earlier seemingly unrelated studies. A few years back, two separate research projects were being conducted by Nazareth chemistry majors. One explored the effects of a bacteria that used the small molecule, dipicolinic acid (DPA), as a source of nutrients when calcium is present; when the DPA was added to water that contained calcium, most of that metal would fall out of the water as a precipitant.

鈥淒PA is a well-researched molecule that [scientists] don鈥檛 have a lot of interest in anymore,鈥� says Tajc, assistant professor of organic chemistry. 鈥淚 think it鈥檚 considered kind of boring.鈥�

The second research project was devoted to hydrofracking, and when Tajc heard of the two parallel studies, a light bulb went off. In fracking, the presence of metal in water is a big problem. Could that small molecule be the solution?

Water, Water Everywhere鈥�

First employed in the mid-20th century, hydraulic fracturing is today the most common technique for obtaining natural gas from shale rock beds buried deep beneath our planet鈥檚 surface. The process requires drilling thousands of feet, then injecting a high-pressure solution that eventually cracks the rock, creating fissures from which the gas can escape and be captured.

A typical fracking liquid is comprised of fresh water鈥攎illions of gallons are used in every fracking well鈥攎ixed with chemical additives that amplify its effectiveness in the subterranean process. But after spending time underground amid all those minerals, the water is anything but fresh: It becomes suffused with extremely high levels of calcium, barium, magnesium, strontium, and other metals that are toxic in high doses. (Strontium, for example, has radioactive properties that have no place in potable water.)

According to Environmental Protection Agency guidelines, fracking wastewater contains 400,000 times the maximum allowable safe levels of those minerals鈥攆ar beyond the capabilities of conventional water purification processes. As it can鈥檛 be returned to the water supply or re-used for fracking, the wastewater is often disposed of through injection back into the earth; but as fracking activity has increased throughout the United States, the pent-up pressure created by that underground disposal has been linked to fracking-related earthquakes. An alternative storage method involves holding ponds in which the water is left to evaporate over time鈥攂ut there are several reports of fracking holding ponds in the southwestern U.S. that have leached contaminated water into the soil and local water supply.

Would it be fair to call fracking water 鈥� toxic waste? 鈥淲ell, it鈥檚 definitely waste, and it鈥檚 definitely toxic,鈥� Tajc says. 鈥淵es, I鈥檇 say that鈥檚 fair.鈥�

The DPA Solution

Finding a way to remove the minerals from the water would eliminate the need for these risky disposal methods and enable potable water to be returned to our country鈥檚 available supply. 鈥淲hen you think about the serious water shortages experienced by the western half of the country, that alone is an issue worth addressing,鈥� Tajc says.

Inspired to combine the principles behind those two studies, he headed to the lab to begin the process of determining DPA鈥檚 effectiveness in stripping the harmful metals from fracking wastewater. 鈥淲e found we could extract 95 percent of the calcium by using this small molecule,鈥� he says. 鈥淭hen it turned out that the process also worked on strontium. It鈥檚 not as efficient [as calcium]鈥擨 think we鈥檝e seen as high as 65 to 70 percent removal鈥攂ut that鈥檚 better than anything else that鈥檚 been shown so far.鈥�

More study is needed to find ways to increase the amount of calcium and other metals that can be removed from fracking wastewater using DPA. In time, he adds, there鈥檚 no reason why the same basic methodology couldn鈥檛 also be used to remediate water that has been contaminated through other means鈥攚ith lead, for instance, or even the halogens found in the waters of the Finger Lakes.

鈥淩ight from the start we saw very good results from this,鈥� he says. 鈥淏ut I wasn鈥檛 satisfied with good. I wanted to make it better.鈥�

A Team Effort

The work to refine and improve DPA鈥檚 effectiveness has been going on now for a little more than three years. 鈥淎t its most fundamental, it鈥檚 a simple chemical reaction,鈥� Tajc says. 鈥淵ou need to chemically modify a little bit at a time to see, Did I improve it? Did I make it worse?鈥�

He compares these ongoing research efforts to the iterative steps that must be taken to refine a new medicine before it can be used. 鈥淵ou don鈥檛 cure something with the initial discovery鈥攊nstead, you improve it to make sure it does the best job it can.鈥�

This painstaking approach, called a structure-activity relationship, is critical to nudge the DPA procedure to its ultimate effectiveness. And it鈥檚 a team effort: Tajc estimates that more than 40 students have contributed to the project to date, including some who start as early as their freshman year. 鈥淭he work that we鈥檙e doing is the kind of thing I teach in Organic Chemistry,鈥� he says, 鈥渟o freshmen get a chance to experience those processes before they take the class as a sophomore.鈥�

Shane Fuentes 鈥�18 agrees. Although he didn鈥檛 expect to have this kind of opportunity prior to coming to Nazareth, the biochemistry major was excited to learn he would be able to dive into Tajc鈥檚 research as a freshman.

鈥淎t a larger school I might have had an opportunity to participate in some basic research by now, but I鈥檇 probably just be holding test tubes for a senior or a grad student,鈥� says Fuentes, now a sophomore. 鈥淎nd it made Organic Chemistry a lot easier when I took the course.鈥�

The practice of bringing students into research projects early is becoming more commonplace at Nazareth, says William Lammela, Ph.D., chair of the Chemistry and Biochemistry Department. 鈥淭he research makes the knowledge real. It brings the content alive,鈥� he says. 鈥淎nd in this case they can relate to it in an even more powerful way鈥攖hey can see how work they鈥檙e participating in is directly addressing a social problem.鈥�

Tajc is also supported in his DPA research by his fellow faculty: he鈥檚 working with Lammela on the analytical chemistry that helps determine exactly how much of the metals have been removed from the water; and Stephanie Zamule, Ph.D., assistant professor of biology, is assisting on the portions of his work that delve into toxicology and microbiology. 鈥淭hose aspects are out of my area of expertise,鈥� Tajc says. 鈥淚t鈥檚 wonderful to work in an environment where this kind of collaboration can occur.鈥�

Teachable Moments

Tajc is uncertain how long it will be before his process is ready for commercial applications, but 2016 could be a big year for the DPA technique: In January he presented his research to date as a keynote speaker at the international Latin American Congress of Chemistry in Concepcion, Chile. 鈥淚鈥檝e never given away what the bacteria is or exactly how we do the process before鈥攖his [was] the first time,鈥� he says.

The reaction to Tajc鈥檚 work was uniformly positive, though muted by South America鈥檚 lack of involvement in hydraulic fracturing. Still, experts at the Chilean conference quickly picked up on the broader applicability of his research. 鈥淭hey began to see how the process could improve water quality across the board,鈥� he says. 鈥淐opper mining is a major industry in that country, for example, and this process might be able to play a role in that.鈥�

Chile was his first detailed presentation on this topic, but three years ago Tajc presented the fundamentals of what would become his DPA technique at an American Chemical Society Nation Meeting in San Francisco that featured a hydraulic fracturing symposium. There, he discovered his was a lone voice advocating for innovative solutions to the issue. 鈥淓veryone was talking about the effects of the contaminated wastewater, but no one was talking about ways to remediate it,鈥� he says.

Following his San Francisco presentation, a representative of a major oil company approached Tajc to praise his early work. 鈥淗e called it a 鈥榞ame-changer鈥� for hydrofracking,鈥� Tajc recalls. 鈥淭hat was exciting to hear 鈥� it helped show me that we were on to something.鈥�

鈥淎 Neutral View鈥�

Although the potential benefits of Tajc鈥檚 research would resolve some of the negative aspects of hydraulic fracturing, the educator says he鈥檚 not taking a stand on the issue of fracking itself.

鈥淚 try to have a very neutral view,鈥� he says. 鈥淣o matter what type of process you鈥檙e getting energy from, there鈥檚 always going to be some sort of environmental impact. The wastewater is just the effect of this process.鈥�

On the other hand, he鈥檚 also a native of southwestern Pennsylvania, where coal mining was once a major source of employment鈥攁nd where his grandfather, a miner, died of black lung disease. Now, hydraulic fracturing in that region鈥檚 Marcellus Shale formation has bolstered a once-foundering economy.

鈥淗ydrofracking has brought life back into my hometown, but at what cost?鈥� Tajc wonders. 鈥淥n the surface it鈥檚 not nearly as bad [as coal mining], but it鈥檚 only been going on for 10 years. We don鈥檛 really know yet.

鈥淭hat鈥檚 why I鈥檓 trying to take the middle road. I see a recognized problem, and I鈥檓 trying to offer a solution.鈥�

With the first detailed presentation of his work behind him, Tajc is now working on a scholarly article that he hopes to see published this year. It may be years before the full industrial potential of the DPA process can be realized, but he鈥檚 excited that his research, even in these early stages, might be able to 鈥渟park a conversation鈥� on the issue of what to do about fracking wastewater.

And in the meantime, as a scientist he鈥檚 simply looking forward to getting as much feedback as possible. 鈥淲hen it comes to science, the peer review is everything,鈥� he says. 鈥淵ou may think you鈥檙e doing phenomenal work, but if others don鈥檛 agree, you can learn from that as well.鈥�

Erich Van Dussen is a freelance writer in Rochester, New York.