Meet EPA Soil Scientist Chunming Su, Ph.D.
EPA soil scientist Chunming Su, Ph.D., studies fate and transport of contaminants in the subsurface and develops cost-effective remedial methods for treating contaminated groundwater and soil. Dr. Su has also worked as a soil scientist for the U.S. Department of Agriculture.
Tell us about your educational and science background.
In 1980, when I was 16 years of age, I went to China Agricultural University to study soil science and agricultural chemistry. I was the first person in my extended family to go to college. I went to the University of Guelph, Canada in 1986 to study for a master’s degree in boron soil chemistry and plant nutrition. Guelph had the best agricultural college in Canada and the education and training I received there are indicative of that quality. My advisor at Guelph strongly encouraged me to continue my graduate study in the United States, an idea that had been steadily gaining ground in my own mind. So, I rode a Greyhound bus for two days and two nights from Toronto, Canada to arrive at Porthill, Idaho, US Customs and Border Protection on August 14, 1988 on my way to Pullman, Washington State. I was nervous to learn that I was the only one among a busload of travelers required to go through an interview with an immigration officer, but I was encouraged by the huge waving American flag on a tall post outside the building. I explained politely to the officer that I was going to Washington State University to study soil science, not social science, as she thought. For the next four years, I did my doctoral research on the thermodynamics and surface chemistry of two nanosized soil minerals – allophane and imogolite, further enriching my education and research experience. With a newly minted PhD, I went to United States Salinity Laboratory, Riverside, California to work as a postdoctoral research associate on trace element geochemistry in arid regions. Then I came to EPA’s lab in Ada, Oklahoma to do research on groundwater and soil remediation in 1996 and have stayed here ever since.
When did you first know you wanted to be a scientist?
I had a great teacher in my middle school who taught both physics and chemistry to our class. He explained laws of physics and chemistry in a way that students could easily understand, using real-world natural phenomena (lightning, rainbow, sunset, sunrise, wildfire, earthquake) and human endeavors (trains, airplanes, submarines, rockets, satellites). He demonstrated chemical experiments in unforgettable fashion. He once produced hydrogen gas and oxygen gas into two separate bottles by electrolysis of water, put the bottles next to a small flame, and then opened the bottles. Suddenly we heard a loud BANG!! Every student was excited – the teacher decomposed water and made it come back! How magical this is! Chemistry proved such a fun science that I knew my career would be related to chemistry and I would work as a scientist.
What do you like most about your research?
My research seeks cost-effective solutions to problems related to soil and groundwater pollution. I like the challenge of developing novel methods and approaches to treat contaminants situated in their original place. The nature of my work demands multi-disciplinary collaboration to tackle practical problems. I am a member of a team doing pioneering work using zerovalent iron (ZVI) and compost materials to remove organic (dense nonaqueous liquid chlorinated solvents) and inorganic (arsenic, chromate, nitrate) substances from groundwater. ZVI and carbonaceous materials have been used to construct permeable reactive barriers to intercept and treat contaminated plumes. I have conducted a field scale test at the Parris Island, South Carolina Superfund site to evaluate long-term performance of emulsified zerovalent iron (EZVI) for treating source zone chlorinated solvents. A colleague and I have developed a method to convert toxic hexavalent chromium to none-hazardous trivalent chromium using a mixed ferrous sulfate and sodium dithionite solution, leading to a US patent. This method was used to treat hexavalent chromium in groundwater at a Superfund site in North Charleston, South Carolina. Recently I have been involved in studies to evaluate fate and transport of nanomaterials including nanohybrids in saturated porous media and to explore applications of nanomaterials for environmental remediation.
How does your science matter?
Many contaminated sites, including Superfund sites, require treatment on site to save money and time. Our patented technology (A Method of Treating a Subsurface Formation with Ferrous Iron to Reduce Contaminants to Harmless Species. United States Patent # 7,166,228 B2) was successfully used at the MacAlloy Superfund site for treating hexavalent chromium in groundwater, saving more than one million dollars in cleanup cost. In November 2006, EPA recognized the site as the Superfund program’s 1,000th Construction Completion at a celebration held at the site. In pioneering work on natural attention of contaminants in the subsurface, my studies have shown that reduction/oxidation sensitive minerals such as green rust and iron oxides contribute to abiotic degradation of organics and immobilization of toxic heavy metals. Active treatments combined with natural attenuation processes could potentially accelerate contaminant removal and destruction. Recently I have joined research efforts on remediation of per- and polyfluoralkyl substances in groundwater, and beneficial use of waste materials such as biochar for heavy metal and fluoride removal from contaminated water.
Nanomaterials are increasingly being used in pesticides and consumer products. It is important to assess potential risks of nano-enabled pesticides and consumer products to human health and the environment. I am currently involved in studies to investigate fate and transport of nanomaterials including nanohybrids and nanocomposites in saturated porous media. Our results will be used by EPA to develop and improve guidelines to regulate nanomaterials, and by states, local governments, and practitioners to better manage risks of nanomaterials to ensure chemical safety for sustainability.
If you weren’t a scientist, what would you be doing?
I grew up in a rural village where life was tough but also enjoyable at times. I worked hard to do farming work such as transplanting rice seedlings in the paddy fields and catching loaches, swamp eels, and fish for food. I once caught a five-pound grass carp in a river barehanded on a day when my father had just finished constructing our new mud-brick house. The fish was considered as an omen for good fortune and my family was very much enlightened. I had a good Chinese language teacher in my early school years who inspired me to learn and practice writing skills. I liked reading novels and storybooks and enjoyed writing about life and work around me. My essays and stories about countryside life and hard-working farmers in my hometown village in Hunan Province, China, were broadcast in my village and neighboring villages through public loudspeakers when I was a middle school student. I enjoyed interviewing and reporting on local people. So, I would probably have become a journalist or writer if I weren’t a scientist.
What advice would you give a student interested in a career in science?
People will do well in an area in which they are interested. Success is largely derived from self- motivation, which comes from a keen interest in a subject. I would highly encourage students to find and cultivate an interest in a specific field of science as early as possible. College students should take advantages of internships such as the Environmental Research Apprenticeship Program (ERAP), McNair Scholars Program, and Pathways Internship Program, which are available at EPA’s lab in Ada, Oklahoma, and elsewhere. I personally have served as a mentor to numerous college students in all these programs and both my students and I have enjoyed and benefited from them.
If you can have any superpower, what would you choose?
I always dreamed of time travel by which I would be able to see the beginning of time and the future of humanity. We are experiencing unprecedented changes in demography, science, technology, lifestyle, and the environment. Peace and development remain the dominant themes of the world. Still, potential risks, including environmental degradation, must be evaluated and managed. A superpower such as time travel can in theory help us live and prosper in a safe and sustainable world.
What do you think the coolest scientific discovery was and why?
I would choose electricity. That is the heart of so many modern technologies, with electrical power and electronics at the top of that list. An individual electron is so small and insignificant, yet many electrons can be organized to work together to impose great forces to change the world we live in. We take electricity for granted until we lose it in a disaster or accident. The essence of chemistry is the study of transfer of electrons from one atom to another and sharing of electrons among different atoms. The treatment of contaminants also involves removing or giving electrons to hazardous substances to make them into harmless forms. How wonderful are the electrons when they become our friends!
What do you think is our biggest scientific challenge in the next 20/50/100 years?
How to get help from science to strike a good balance between economic development and environmental protection is the biggest challenge in the next 20 years as we are witnessing accelerated degradation of the environment and increasing extreme weather; How to advance science to help cure cancer is the biggest challenge in the next 50 years as we are seeing more younger people suffering from cancer; How to use science to help humans prevent World War III and to keep the world peaceful and prosperous is the biggest challenge in the next 100 years as we see ever changing geopolitical landscapes demanding all peoples of the globe work together to decrease and resolve political, economic, and cultural conflicts. After all, we have only one Earth to call home for the entire humankind.
If you could have dinner with any scientist, past or present, who would you choose? And what would you talk about?
I would like to have dinner with Albert Einstein, the science giant who revolutionized our thinking about space and time. I would ask him about what leads to creativity and how scientists could develop and improve creativity in scientific research. Albert Einstein once said "Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution". However, current educational systems and research organizations are far from satisfactory in cultivating and facilitating creativity. Can you imagine how much more we could achieve if we all became more creative?
I would also like to have dinner with University of Texas at Austin professor John Goodenough, at 97-years of age, the oldest ever Nobel laureate awarded in chemistry in 2019. I would ask him how he managed to work for a PhD in physics after getting a BS degree in mathematics. Then, how did he manage to get a professorship at University of Oxford to lead an inorganic chemistry lab without a degree in chemistry? How did he convince UT Austin to offer him a position in the Department of Mechanical Engineering at the age of 64, when many professors would be considering retiring? I admire UT Austin’s open-arms gesture and flexibility in providing him with the necessary resources to continue his research on lithium-ion batteries. How did he maintain a productive and healthy life? I see an excellent amalgamation of two ingredients of Professor Goodenough’s success: interdisciplinary research (sound mind) and perseverance (healthy body). How great it would be if more scientists in their senior years can continue to make contributions to the society without burdening the social security and health systems.
Editor's Note: The opinions expressed herein are those of the researcher alone. EPA does not endorse the opinions or positions expressed.