Let’s step away from agriculture for a moment to have a look at energy. But really, if you’re doing your homework, you know that industrial agriculture does not solely rely on energy from the sun to power photosynthesis, rather it is heavily dependent on fossil fuels for machinery, fertilizer, biocides, seeds, etc. For example, methane (the main constituent of natural gas) is used in the Haber-Bosch process for synthesizing nitrogen fertilizer, consuming about 3-5% of the world’s natural gas production . These days, you can’t get away with talking about natural gas production without talking about hydraulic fracturing (or “fracking”) and horizontal drilling (see illustration above). And since my roots are in western Pennsylvania, I’ve been following how fracking the Marcellus Shale has transformed the landscape and the economy in that area. Here I’ve summarized a publication from this past February in the journal Water Resources Research by Brian Lutz, Ph.D. and others. The major finding was (spoiler alert!) that fracking produces much less wastewater per unit energy than conventional natural gas drilling .
Wastewater treatment and storage is one of the leading environmental and human health concerns over fracking. There are three main pools of wastewater generated. First, “flowback” refers to frac fluids that have returned to the surface. Frac fluids are water mixed with various chemicals (including health and environmental toxins) to aid in the fracturing process. Second, “drilling fluid” is the water plus other additives to cool and lubricate the drill head. Finally, “brine” refers to the naturally occurring subsurface water that is brought to the surface as a byproduct of the drilling process. Typically this water is highly saline, hence the name, and can be even more toxic than the flowback, often containing high concentrations of metals, organic compounds and sometimes radioactive materials–all of which are naturally occurring and not contaminated as a result of the drilling process. Fracking wastewater is approximately 45% brine, 43% flowback, and 12% drilling fluid while conventional wastewater is approximately 87% brine, 8% plowback, and 5% drilling fluid.
What to do with this wastewater once it has reached the surface? Conventional natural gas drilling typically occurs in regions where the geology allows for the wastewater to be reinjected into deep geologic formations, essentially avoiding any need to treat the water or posing a threat to human or environmental well-being. However, the Marcellus Shale’s geology is such that reinjection is not possible. So dealing with wastewater from natural gas production is relatively new and legislation has evolved alongside the practice. Disposal of the wastewater has transitioned from municipal water treatment facilities (peaked in 2008 and is still the main mode of disposal for conventional well wastewater), to industrial water treatment (peaked in 2009 and 2010), to current efforts to reinject or recycle the wastewater. As lawmakers recognized that municipal facilities were not suited for dealing with such high total dissolved solids (TDS), industrial facilities were sought for processing the wastewater. However even industrial treatment facilities are incapable of removing the majority of ions that contribute to the high TDS wastewater. So the surface water neighboring the industrial treatment facility receives high TDS loads from the “treated” wastewater. Notably, most industrial wastewater treatment facilities in Pennsylvania are located in the Ohio River basin, so between 2009 and 2011 fracking well operators in eastern PA (Delaware or Susquehanna River basins) seeking industrial treatment facilities sent nearly 50% of their wastewater west to the Ohio River basin.
Guidelines constraining municipal and industrial treatment of the fracking wastewater increased demand for underground injection disposal since 2011. Due to the underlying geology of this region, there are only 7 commercial injection wells in Pennsylvania, 3 in West Virginia, and 184 in Ohio. In order to transport the wastewater to the injection wells, big rig trucks haul the wastewater sometimes hundreds of miles, mainly to Ohio. Since Ohio has recently experienced earthquakes believed to be associated with the wastewater injections, there is likely to be new regulations limiting injection disposal. Recycling wastewater makes some sense but has a limited capacity in that it depends on the installation of new wells to make use of the recycled wastewater.
This seems like a lot of trouble dealing with this wastewater, how is it economically feasible? According to Lutz and his co-auth0rs, “The average Marcellus well produced only approximately 35% of the amount of wastewater per unit gas recovered when compared to conventional wells.” In other words, conventional drilling produces about 13.4 liters of wastewater per million Btu gas energy while fracking produces only 4.8 liters of wastewater per million Btu gas energy. The authors continue, “However, Marcellus wells collectively generated approximately 570% more wastewater in 2011 than conventional wells.” This massive generation of wastewater is the result of dramatic increases in number of fracked wells and the lucrative amount of gas recovered from each well despite fracked wells’ greater efficiency in wastewater production over conventional wells.
While fracking appears to be wastewater intensive, this is a product of the size of the Marcellus Shale and not the method of drilling. Only ~1% of the Marcellus Shale has been explored, so the arms’ race between fracking technology and environmental regulation will continue to play out for years to come.
 pdf file of the original article: Lutz et al 2013 WRR Gen, transp, disposal of wastewater assoc’d with Marcellus Shale
Most of the fundamental ideas of science are essentially simple, and may, as a rule, be expressed in a language comprehensible to everyone. — Albert Einstein
My friend and fellow scientist, Shengpan Lin, and I have been thinking about the importance of science communication. Among scientists, we generally assume that any time spent communicating our research to non-scientists is time spent not being productive, which ignores how communication also benefits scientists themselves. This communication is a two-way exchange of information, not just one-way broadcasting.
Often, presentations can come across as “too technical” or using “too much jargon” leading to scientists themselves coming across as “spending too much time in their head” and not caring about the audience’s interests. If scientists create their presentations for non-scientist audiences by simply making adjustments to existing presentations for a scientific audience, the presentation is not likely to be useful for the audience or help the scientist nurture a working relationship with the audience members.
When communicating with non-scientist audiences, scientists need to consider what the audience is most concerned with, what their experiences might be with the topic, their level of knowledge of the topic (do not underestimate this!), and most essentially how the scientist can connect with the audience. We suggest that scientists consider these elements when outlining their presentation before deciding on the content of the presentation. We came up with a checklist to help you get started (see Box 1 below). This process involves taking a step (or several steps) back and looking at the big picture, i.e. ask yourself, where does my research fit into society? This may involve thinking and talking about things you don’t normally think and talk about because you take them for granted. Every scientist thinks their own research is important but rarely do we think critically about how to explain its importance to others, except briefly in the opening line of a grant proposal or article. Give this a try and drop us a line with your feedback!
Check out my guest posting on the Kellogg Biological Station Long Term Ecological Research (LTER) blog:
The dark cloud:
Normally discussion of water pollutants involves tiny particles invisible to the human eye, but this week thousands of dead pigs have been dumped into the river running through Shanghai. Who dumped the pigs and why remains unknown. I’ve spent enough time on rivers and in streams to know that they are often used as a dump for trash, including large items like tires, grocery carts, rolled up carpet, and old television sets. But dead pigs floating down river provoke an eerie feeling with their human-like appearance (fleshy rather than furry, plump). I don’t mean to invoke an animal rights activist tone, I simply mean to reflect on this wasteful loss of life.
The silver lining:
Recent Chinese government food safety crackdowns on farmers selling dead and diseased pigs to slaughter houses might have led the person responsible to dump these bodies rather than try to sell them.
For more on this story see:
“Thousands of dead pigs found in Chinese river”
“A tide of dead pigs in China but dinner is safe” **warning photos may be offensive.
More and more evidence points to how empowering women is key to economic stability, food security, and human well-being. The role of women in agriculture, especially in developing nations, and their vulnerability to ecosystem degradation is often overlooked. According to the Millennium Ecosystem Assessment (2005):
Significant differences between the roles and rights of men and women in many societies lead to women’s increased vulnerability to changes in ecosystem services. Rural women in developing countries are the main producers of staple crops like rice, wheat, and maize. Because the gendered division of labor within many societies places responsibility for routine care of the household with women, even when women also play important roles in agriculture, the degradation of ecosystem services such as water quality or quantity, fuelwood, agricultural or rangeland productivity often results in increased labor demands on women. This can affect the larger household by diverting time from food preparation, child care, education of children, and other beneficial activities.Yet gender bias persists in agricultural policies in many countries, and rural women involved in agriculture tend to be the last to benefit from—or in some cases are negatively affected by—development policies and new technologies.
And more from a noteworthy Op-Ed in the New York Times by Olivier De Schutter (3 Mar 2013) discussing the “Feminization [meaning a disproportionate number of farmers are women] of Farming”:
Across the developing world, millions of people are migrating from farms to cities in search of work. The migrants are mostly men. As a result, women are increasingly on the front lines of the fight to sustain family farms. But pervasive discrimination, gender stereotypes and women’s low social standing have frustrated these women’s rise out of poverty and hunger.
Discrimination denies small-scale female farmers the same access men have to fertilizer, seeds, credit, membership in cooperatives and unions, and technical assistance. That deters potential productivity gains. But the biggest barriers don’t even have to do with farming — and yet they have a huge impact on food security.
As sole or principal caregivers, women and girls often face a heavy burden of unremunerated household chores like cooking, cleaning, fetching water, collecting firewood and caring for the very young and the elderly. These uncompensated activities are equivalent to as much as 63 percent of gross domestic product in India and Tanzania. But they result in lost opportunities for women, who don’t have the time to attend classes, travel to markets to sell produce or do other activities to improve their economic prospects.
To be sure, some female-headed farm households get remittances from absent men, but that is often not enough to compensate for the economic pressures they face. And we know that when women get more education and improve their social and economic standing, household spending on nutrition increases, child health outcomes improve and small farms become more productive…[read the rest of the article here].
A new article published in the highly respected scientific journal Proceedings of the National Academy of Science (PNAS) reports on a “perfect storm” of conditions ripe for microbes to develop antibiotic resistant genes in Chinese hog factory farms (1). Adding antibiotics and trace metals to livestock feed to promote growth is nothing new in industrialized farming–of total antibiotics consumed in the US annually, 80% are consumed by livestock (2). By mass of antibiotics, Chinese livestock consume 4x as much as the US (1). The authors of the study (including researchers from Michigan State University, where AGua’s author is currently enrolled) found 149 unique antibiotic resistance genes among soil samples of material from manure processing and land disposal compared with control soil samples. The abundance of antibiotic resistance genes was directly correlated with the concentration of antibiotics and trace metals (1). These antibiotic resistant microbes pose a serious threat to global human health because they are not removed by treatment or processing, and manure from livestock factory farms is typically disposed of by spreading on surrounding farm land as fertilizer. Once applied to the soil the microbes are able to share their genes with other microbes and travel through the environment, entering streams and water supplies. Read more about this in the link to reference 1 below or this NY Times article.
Jim Hansen was one of the first scientists to speak out about climate change and has devoted much energy since to raising awareness. In this quick video from Andrew Revkin’s Dot Earth blog for the NY Times, Jim Hansen discusses climate change in terms of “loaded dice”, what is needed from US policy makers, the role of coal, and the importance of developed nations’ responsibility for historical CO2 emissions.