Navigation Links
Fracking flowback could pollute groundwater with heavy metals
Date:6/25/2014

ITHACA, N.Y. The chemical makeup of wastewater generated by "hydrofracking" could cause the release of tiny particles in soils that often strongly bind heavy metals and pollutants, exacerbating the environmental risks during accidental spills, Cornell University researchers have found.

Previous research has shown 10 to 40 percent of the water and chemical solution mixture injected at high pressure into deep rock strata, surges back to the surface during well development. Scientists at the College of Agriculture and Life Sciences studying the environmental impacts of this "flowback fluid" found that the same properties that make it so effective at extracting natural gas from shale can also displace tiny particles that are naturally bound to soil, causing associated pollutants such as heavy metals to leach out.

They described the mechanisms of this release and transport in a paper published in the American Chemical Society journal Environmental Science & Technology.

The particles they studied are colloids larger than the size of a molecule but smaller than what can be seen with the naked eye which cling to sand and soil due to their electric charge.

In experiments, glass columns were filled with sand and synthetic polystyrene colloids. They then flushed the column with different fluids deionized water as a control, and flowback fluid collected from a Marcellus Shale drilling site at different rates of flow and measured the amount of colloids that were mobilized.

On a bright field microscope, the polystyrene colloids were visible as red spheres between light-grey sand grains, which made their movement easy to track. The researchers also collected and analyzed the water flowing out of the column to quantify the colloid concentration leaching out.

They found that fewer than five percent of colloids were released when they flushed the columns with deionized water. That figure jumped to 32 to 36 percent when flushed with flowback fluid. Increasing the flow rate of the flowback fluid mobilized an additional 36 percent of colloids.

They believe this is because the chemical composition of the flowback fluid reduced the strength of the forces that allow colloids to remain bound to the sand, causing the colloids to actually be repelled from the sand.

"This is a first step into discovering the effects of flowback fluid on colloid transport in soils," said postdoctoral associate Cathelijne Stoof, a co-author on the paper.

The authors hope to conduct further experiments using naturally occurring colloids in more complex field soil systems, as well as different formulations of flowback fluid collected from other drilling sites.

Stoof said awareness of the phenomenon and an understanding of the mechanisms behind it can help identify risks and inform mitigation strategies.

"Sustainable development of any resource requires facts about its potential impacts, so legislators can make informed decisions about whether and where it can and cannot be allowed, and to develop guidelines in case it goes wrong," Stoof said. "In the case of spills, you want to know what happens when the fluid moves through the soil."


'/>"/>

Contact: Melissa Osgood
mmo59@cornell.edu
607-255-2059
Cornell University
Source:Eurekalert  

Related biology news :

1. Another concern arises over groundwater contamination from fracking accidents
2. Hormone-disrupting activity of fracking chemicals worse than initially found
3. How to avoid water wars between fracking industry and residents
4. Acid mine drainage reduces radioactivity in fracking waste
5. UTSA, Southwest Research Institute to develop low-cost method to treat fracking water
6. First risk assessment of shale gas fracking to biodiversity
7. Many stressors associated with fracking due to perceived lack of trust, Pitt finds
8. Fracking: Challenges and opportunities
9. Fracking in Michigan: U-M researchers study potential impact on health, environment, economy
10. UMN scientists get federal grant for biotechnology development to purify fracking water
11. Fracking and Health Impact Assessments -- IOM hosts workshop April 30 and May 1
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Fracking flowback could pollute groundwater with heavy metals
(Date:3/23/2016)... 2016 Einzigartige ... und Stimmerkennung mit Passwörtern     ... MESG ), ein führender Anbieter digitaler Kommunikationsdienste, ... SpeechPro zusammenarbeitet, um erstmals dessen Biometrietechnologie einzusetzen. ... Möglichkeit angeboten, im Rahmen mobiler Apps neben ...
(Date:3/17/2016)... LONDON , March 17, 2016 ... market intelligence, forecasts the global biometrics market will ... an impressive 118% increase from 2015. Consumer electronics, ... with embedded fingerprint sensors anticipated to reach two ... Dimitrios Pavlakis , Research Analyst ...
(Date:3/11/2016)... Germany , March 11, 2016 http://www.apimages.com ... - Cross reference: Picture is available at AP Images ( http://www.apimages.com ... from DERMALOG will be used to produce the new refugee identity ... other biometric innovations, at CeBIT in Hanover ... scanner from DERMALOG will be used to produce the new refugee ...
Breaking Biology News(10 mins):
(Date:5/23/2016)... (PRWEB) , ... May 23, 2016 , ... ... interest organization focused on molecular nanotechnology, announced the winners for the 2015 Foresight ... physicist Richard Feynman, are given in two categories, one for experiment and the ...
(Date:5/20/2016)... , ... May 20, 2016 , ... Kablooe Design, a ... companies, today announced its official 25th anniversary of the business. “We have worked hard ... grateful to our customers for the privilege and honor of serving their product design ...
(Date:5/19/2016)... ... , ... Anton Paar USA, located in Ashland, Virginia is pleased to announce ... structure adds a third office building to the current facilities. , Growth is ... land, along with office space adjacent to the previous main building. Through remodels and ...
(Date:5/19/2016)... ... May 19, 2016 , ... ... (CRO) has welcomed Abu Siddiqui as Director, Large Molecule & Biomarker Bioanalysis. , ... vaccine and translational biomarker discovery studies for preclinical and clinical safety programs. “We’ve ...
Breaking Biology Technology: