From pages 32, 33 34 & 35 of Royal Dutch Shell and its sustainability troubles Background report to the Erratum of Shells Annual Report 2010
The report is made on behalf of Milieudefensie (Friends of the Earth Netherlands)
Author: Albert ten Kate: May 2011.
Shell: nothing wrong with fracking and unconventional gas
In its communication, Shell makes no difference between conventional and unconventional gas in terms of environmental and health risks. The company generally refers to natural gas as being cleaner-burning than coal in power plants and as being a bridge to a low-carbon energy future.
On fracking, Shell states on its website: This is a safe and proven technique according to the U.S. Environmental Protection Agency (EPA), which is now carrying out a new study into hydraulic fracturing and its potential impact. Fracturing has been used by oil and gas companies for over 60 years. The company does not mention that there are great differences between the traditional fracking and the present high-volume fracking, that the EPA has been presently accused of hiding some severe impacts of fracking, and that the U.S. government has not been able and/or willing to monitor the booming U.S. shale gas business adequately.
Environmental and health risks caused by unconventional gas extraction
In this section, the environmental and health risks of the present high-volume fracking are considered more in-depth.
1) Enormous water use
According to the U.S. Environmental Protection Agency, the volume of water needed for hydraulic fracturing varies by site and type of formation. Fifty thousand to 350,000 gallons of water may be required to fracture one well in a coal-bed formation, while two to five million gallons of water may be necessary to fracture one horizontal well in a shale formation. A gallon stands for 3.78 litres.
Shell stated in September 2010 that hydraulic fracturing requires 1 to 5 million gallons of water per well and that it re-uses some of the water. For its Groundbirch tight gas operations in British Columbia (Canada) Shell claims to use 5 to 8 million litres per well, sourced locally from the Peace River, fresh water wells and some 20-40% recycled from producing wells. As with most unconventional gas operations presently going on, the Groundbirch operations have just been starting up. As of June 2010 Shell had drilled 103 wells, with almost 3,000 wells yet to come. Shell’s future aspiration is to use reclaimed water from a waste treatment plant at Groundbirch, transported via pipelines so the present disposal by trucks can be reduced.
To explore the shale gas possibilities of the Karoo region in South Africa, Shell states it may decide to hydraulically fracture vertical and horizontal exploration wells. It expects to need up to 2.2 million litres of water for hydraulic fracturing a vertical exploration well and up to 6 million litres for an exploratory horizontal well section. Whenever Shell is allowed to explore the Karoo region, and it does find gas it could produce on an economically basis, one wonders how Shell would cope with the enormous amounts of water needed in the semi-desert Karoo region. Shell has not yet shared its thoughts about this.
2) Pollution of water resources
There are several ways in which water could be polluted through high-volume fracking. With shale gas production, the two major pathways to water contamination are activities at the surface and errors below ground: ? Once in the ground, a large portion of the fracturing fluid may be trapped in the target formation. The rest, however, comes back to the surface (flowback), combined with water produced from the formation itself. Both flowback and produced water represent large waste streams. If flowback and produced water are disposed of improperly, waste water may threaten public and environmental health.
? Errors below ground can endanger water resources as well. Improperly cased wells may contaminate penetrated aquifers. Potential shallow pockets of natural gas in formations above the target layer may enter into ground water.
? Trucks transporting water to the site for fracturing and from the site for disposal may stress nearby stream banks, contributing to erosion and adding sediment to surface water.
Experiences in Pennsylvania, United States
In February and March 2011, the New York Times published several articles about the pollution caused by drilling in Pennsylvania State, USA. During nine months the newspaper had obtained more than 30,000 pages of documents from state and federal agencies/officials.
The shale gas business is booming in Pennsylvania, sitting atop the enormous reserve called the Marcellus Shale. In 2010, drilling companies were issued roughly 3,300 Marcellus gas-well permits in Pennsylvania, up from just 117 in 2007.
The New York Times estimated that more than 1.3 billion gallons of wastewater was produced by Pennsylvania wells over the past three years. Based on the obtained documents, the newspaper estimated that some 10 to 40 percent of the water sent down the well during hydrofracking returns to the surface, carrying drilling chemicals, carcinogenic materials, corrosive salts and, at times, naturally occurring radioactive material. Most of the wastewater was sent by trucks to treatment plants not equipped to remove many of the materials, and ended up in rivers providing drinking water for millions of people. The U.S. Environmental Protection Agency states that it is dangerous when radioactive wastewater contaminates drinking water or enters the food chain through fish or farming. Once radium enters a persons body, by eating, drinking or breathing, it can cause cancer and other health problems, many federal studies show.
The newspaper was able to map the wastewater released from 149 wells. The federal drinking water standards were exceeded for the carcinogenic benzene (41 wells), gross alpha (128 wells, gross alpha is a type of radiation caused by emissions from uranium and radium), uranium (4 wells), and radium (42 wells).203 At least 116 wells produced wastewater exceeding the federal standards for radium or other radioactive materials in drinking water more than 100 times.
3) Greenhouse gas emissions
The three main greenhouse gases (GHGs) that are relevant to the petroleum and natural gas industry are methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O). Methane’s chemical lifetime in the atmosphere is approximately 12 years. Its relatively short atmospheric lifetime, coupled with its potency as a greenhouse gas, makes methane a candidate for mitigating global warming over the near-term (25 years or so). Methane is about 33 and 105 times more powerful at warming the atmosphere than carbon dioxide (CO2) by weight, for a 100-year and 20-year horizon respectively.
New estimates U.S. Environmental Protection Agency
Recently, the U.S. Environmental Protection Agency (EPA) has re-estimated the GHG emissions from the petroleum and natural gas industry. It’s earlier estimations were from 1996. At that stage methane emissions were not considered to be so powerful at warming the atmosphere. In its new study, published in November 2010, the EPA found that CH4-emissions had been significantly underestimated. In its new estimate, the U.S. petroleum and natural gas industry emitted 317 million tonnes of greenhouse gases (measured in CO2 equivalents) in 2006. This is a 57% increase compared to the outdated calculation method. Of the total 317 million tonnes, the natural gas industry accounted for 261 million tonnes CH4 (measured in CO2 equivalents). The EPA had revised four emission sources that were believed to be significantly underestimated: well venting for liquids unloading; gas well venting during well completions; gas well venting during well workovers; centrifugal compressor wet seal degassing venting.
The EPA also made a distinction between the GHG emissions of conventional gas wells and unconventional gas wells. For unconventional wells, it estimated that the emission factors for venting during well completions and well workovers exceed emission factors of conventional wells by a factor 200. It was assumed that all unconventional wells were completed with hydraulic fracturing of tight sand, shale or coal bed methane formations. The water that is returning to the surface is accompanied by large quantities of methane. This is the main cause of the greater methane emissions than conventional wells.
Study Cornell University
In a study published in the journal Climatic Change, the Cornell University in New York assesses the likely GHG footprint of natural gas in comparison to coal.208 The study builds, among other, upon the recent findings of the EPA. The study acknowledges that natural gas produces less greenhouse gas emissions than coal when burned. However, the authors also take into account the GHG emissions that occur during the production of coal and natural gas. This lifecycle approach of GHG emissions from coal and natural gas presents a different picture. The authors compare the lifecycle GHG emissions of shale gas, conventional natural gas (both with low and high estimates for methane emissions to the atmosphere), coal from surface mines, coal from deep mines and diesel oil.
Largely based upon the recent EPA-study, the authors estimate that 3.6% to 7.9% of the methane from shale gas production escapes to the atmosphere through venting and leaks. This is 1.3 to 2.1 times more than from conventional gas operations. The higher emissions from shale gas occur when wells are hydraulically fractured – as methane escapes from flowback return fluids – and during drill out following the fracturing.
Calculated on the basis of a 20-year horizon, the authors conclude that the lifecycle GHG emissions of shale gas are at least 20% greater than the lifecycle GHG emissions of coal. For conventional natural gas, the emissions of coal fall between the high and low estimate.
The 20-year approach by the authors reflects the need to mitigate climate change in the near- term. As methane is known to have a relative short lifetime in the atmosphere, it especially causes climate change on a short-term. The authors also calculated the lifecycle GHG emissions for a 100-year horizon. Over the 100-year frame, the GHG footprint is comparable to that for coal: the low-end shale-gas emissions are 18% lower than deep-mined coal, and the high-end shale-gas emissions are 15% greater than surface-mined coal emissions.
As for Shell, it is not known how many GHG emissions it releases in the air due to venting and leaking CH4. The company promotes natural gas (including unconventional gas) as a replacement for coal. Natural gas is seen by Shell as a bridge to a low-carbon energy future, something for the near-term. However, for unconventional gas the opposite seems true: the GHG emissions increase compared to coal in the near-term.