By Lisa McCrory, NODPA News and Web Editor
Added September 12, 2011.
The United States east coast has a geological formation called Marcellus Shale; a geological formation named for a rock outcropping near Marcellus, NY and covering some 54,000 square miles. This area spreads over eastern Pennsylvania, New York, West Virginia, and Ohio. Within this formation, there will be "hot spots" of gas productivity, but most areas will not likely be productive. Only significant exploration can determine where the productive areas are.
In order to release the natural gas, the rock trapping the hydrocarbons needs to be porous and the Marcellus Shale is less porous than other types of sedimentary rock formations. Drilling a vertical well into a shale formation only draws the gas from the immediate proximity of the well, so though we have known of this natural gas deposit for years and years, getting to it has been a challenge – that is, until the introduction of a process known today as Hydraulic Fracturing or 'Fracking'.
What is Hydraulic Fracturing?
Hydraulic fracturing is the process of fracturing rock to stimulate the flow of oil, gas or water from a reservoir. How does the Fracking Process work? Steel casings are placed into a well at depths of 1,000 – 4,000 feet to protect water supplies from being polluted. Cement is then placed in the space between the drilled hole and the end of the first steel casing. This process is continued until the desired depth has been reached. Using horizontal drilling technology, fracking fluids are pumped into the well at high enough pressure to make the shale rock fracture and for the trapped oil and gas to escape. Each drilling company has a different combination of materials in its fracking fluid, though over 99% of the fluid is water. To keep the cracks open so that gas or oil can escape, a proppant is used, which is usually small grains ofmaterial such as sand. After all this is done, oil and gas is able to flow freely from the well.
Potential problems that organic producers may face from shale gas development:
Groundwater pollution
Natural Gas Exploration can lead to the pollution of streams and stock ponds with methane, road run-off from heavy trucking, drilling fluids, frack water, and flowback. Any of one of these can sicken livestock, pollute the soil with toxins and cause loss of organic certification. What if water becomes unfit to drink? Most upstate municipalities draw their water from underground aquifers, lakes and steams. Most rural properties depend on private water wells for their personal and agricultural needs. Experts suggest that over time most of the toxic underground water will find its way to the surface through fissures, rusted pipes, cracked cement, and conduits of missing and unplugged water and gas wells.
Physical and chemical impacts on farmland
Physical impacts include compaction, erosion and fragmentation of agricultural land (fields are too small to farm). Chemical impacts include contamination, radiation and heavy metals.
Trucking
The intensity of truck traffic in a shale gas area can complicate deliveries of supplies and products to market. It can raise the cost of transportation, and pollute streams.
Fracking flow back waste can be spread on roads as "de-icer" which, over time, can leach into fields at toxic levels.
These topics and more, will be discussed at the NODPA Field Days, (Friday, September 30 from 9:00 am – 10:30 am) including what you can do to mitigate the downsides. In the interim, there are a number of Power Point presentations online that address the potential negative impacts of horizontal hydrofracking:
"Fracking in the Foodshed":
http://my.brainshark.com/Fracking-in-the-Foodshed-5064306
Presentations by Chip Northrup:
http://my.brainshark.com/Search.aspx?slice=1&searchtext=chiptex&sortby=views&msg=1
Posted: to Policy in the News on Mon, Sep 12, 2011
Updated: Mon, Sep 12, 2011