Fracking for natural gas already exists in Virginia. It is very controversial and proponents and opponents are very emotional in the views. Though it is an old method of enhancing yield from a well, the recent advances in fracking and horizontal drilling for natural gas have resulted in the ability to economically access natural gas reserves in shale that the U.S. Geological Survey estimates are equivalent to twice the oil reserves of Saudi Arabia. This is energy security in a turbulent world. The annual production of methane in the United States had increased 30% from 2005 to about 30,171 billion cubic feet of gas a year.
Fracking is the current method of extracting unconventional oil and natural gas that is locked inside impermeable geological formations. Fracking is enabled by horizontal drilling and hydraulic fracturing (thus the name fracking). Fracking or hydraulic fracturing as it is more properly known involves the pressurized injection of fluids made up of mostly water and chemical additives into a geologic formation. The pressure used exceeds the rock strength and the fluid opens or enlarges fractures in the rock. As the formation is fractured, a “propping agent,” such as sand or ceramic beads, is pumped into the fractures to keep them from closing as the pumping pressure is released. The fracturing fluids (water and chemical additives) are partially recovered and returned to the surface or deep well injected for disposal. Natural gas or oil will flow from pores and fractures in the rock into the wells allowing for enhanced access to the methane or oil reserves.
The current debate over fracking centers on the economic benefits, energy security and potential environmental safety of the process. The greenhouse gas emissions from a coal-fired power plant can be reduced by about half and the mercury and sulfur emissions eliminated if the plant is replaced by a natural gas fired power plant. Opponents cite the potential negative health and environmental effects as reasons to ban the practice, while proponents tout its economic benefits, positive environmental impact of cleaner and lower carbon energy than coal, and energy security.
The environmental concerns include air pollution from the operation of heavy equipment, human health effects for workers and people living near well pads from chemical exposure, noise and dust, induced seismicity from the disposal of fracking fluids, and increased greenhouse gas emissions from poor well head control and continued use of hydrocarbons. However, the biggest health and environmental concerns remains the potential for drinking water contamination from fracturing fluids, natural formation waters, and stray gases. If fracking is done carefully and properly the safely extracted gas can reduce air pollution and even water use in electrical generation compared with coal and oil. However, the availability of vast quantities of natural gas is likely to slow the adoption of renewable energy sources and, if fracking is done poorly toxic chemicals from fracking fluid could be released into our water supplies and methane could be release to the air. (See Methane Regulations Coming Our Way and Virginia and EPA’s CO2 Cap)
Virginia has entered this debate, as untapped natural gas deposits are located within certain areas of the Commonwealth. The use of fracking has a long history in Virginia going back to the 1950s. A nitrogen-based foam has historically been used in the fracking process here. Natural gas from conventional reserves and coal bed methane has been produced in the Appalachian plan (in the southwestern area) of the Commonwealth where drilling and coal mining are significant portions of the local economy.
Currently, there are more than 7,700 natural gas wells in the Appalachian plane where drilling required fracking in the extraction process. To date, there have not been any reports of adverse effects on water quality from the fracking. The other environmental impact of an industrial process is not much different from coal mining, dust, constant truck traffic, noise. The expansion of coal bed methane production has been in rural Buchanan and Dickenson counties.
Other areas in Virginia are known to have methane reserves that could be accessed by fracking. The George Washington National Forest is the largest protected forest in the eastern United States at 1.1 million acres in the mountains of Virginia. Approximately half of the forest sits atop the Marcellus shale deposit. The U.S. Forest Service announced November 2014 that it will allow oil and gas drilling using hydraulic fracturing or any other legal and regulatory approved method, but only in the 16% of the forest with existing leases and privately owned oil and gas rights. This final plan reversed a 2011 Environmental Impact Assessment that recommended allowing drilling in 993,000 acres of 1.1-million-acre forest, but banned hydraulic fracking. The finalized plan will allow drilling on 10,000 acres in the forest now leased for energy development and on 167,000 acres whose mineral rights are privately owned. (The government never owned those rights. When the government acquired the land for the forest the owners retained the mineral rights.) Currently, there are no active gas wells in the forest or in surrounding private tracts.
The Taylorsville Basin is located north of Richmond and extends across the Virginia Coastal Plain in the tidewater region of the state. In a 2011 study by the U.S. Geological Survey estimated that the area could contain up to 1.06 trillion cubic feet of natural gas, not huge, but worthwhile economically. Shore Exploration, a Texas-based energy company, has reportedly leased the mineral rights from more than 80,000 acres in Virginia’s Northern Neck and Middle Peninsula spanning large sections of King George, Caroline, Westmoreland, Essex, and King and Queen Counties.
Currently, Virginia law prohibits drilling in the Chesapeake Bay waters and all of the tidal tributaries, but outlines the path for drilling to proceed in the non-prohibited areas of the tidewater region. Whether or not to allow drilling in areas that are not areas identified as part of the Chesapeake Bay waters and tidal tributaries is a regulatory decision, controlled by the Virginia Department of Mines, Minerals and Energy (DMME). Basically, in order to grant a permit, DMME must undertake an environmental impact assessment in consultation with the Virginia Department of Environmental Quality (DEQ). However, DMME is only obligated to consider the findings of the assessment, and ultimately maintains the full authority to issue the permit. Local communities that might be significantly impacted by truck traffic, there is no pipeline, no source of water for a hydraulic fracturing so thousands of truck loads would have to run on small rural roads.
On average, 3-5 million gallons of water are forced under high pressure into each well. Water must be transported to the fracking site in trucks that normally hold approximately 4,500 gallons of water. This means even with reusing the flowback from other wells hundreds of truckloads of water are required for each well. In addition to the mixing trucks that are necessary for adding the required fracking chemicals.
But the major concern over the water use stems from the “flowback” and “produced water” that resurfaces after the rock has been fractured or is produced from the well. It is typical for about a quarter of the water used to return to the surface over the life of the well. Only a small fraction, about 250,000 returns to the surface in the first weeks after the well is drilled. Still the flowback water must be safely collected, stored and treated. An appropriate regulatory structure for addressing flowback does not really exist in Virginia. Typically, large surface ponds are used to store this water, which is polluted with the various fracking chemicals, naturally occurring salts, and naturally occurring radioactive compounds. If the water meets specific standards after being tested, it can be applied to the local land for disposal. If it fails to meet those standards, it must be safely transported to an approved disposal facility. Unfortunately, there is no approved disposal facility.
There is significant concern that the contaminated water would be improperly stored for extended periods of time and could infiltrate into the ground and ultimately contaminate the Potomac Aquifer, which is the sole water supply for over half a million people in eastern Virginia. In addition, extracting natural gas reserves from the Taylorsville Basin would require drilling through the Potomac Aquifer. The real question is where should fracking be allowed?
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