Impact of Hydraulic Fracturing on Water, Wildlife. and Ecosystems

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1 Impact of Hydraulic Fracturing on Water, Wildlife and Ecosystems Angela Sabo Dec 10 th,

2 Introduction Hydraulic fracturing is a technique that uses a high-pressured mixture of water, sand, and chemical additives. The injected mixture will break up rock formations deep under the earth surface. Vertical drilling happens approximately between 3000 to 15,000 feet deep and is followed by horizontal drilling, which makes it possible to fracture large amounts of rock from a single well (Picture1). This technique unlocks gas or oil that otherwise could not be recovered and thereby increases the volume of gas and oil that can be recovered from shale or coalbed deposits. While this method can help provide energy for the future of North America it has also opened up heated discussions surrounding its unprecedented impacts on the environment. Enormous amounts of water are needed for the initial injections, and waste water will work its way into water systems if not properly stored. This paper will focus on the impacts on water removal and water quality, and how this will be mirrored in the surrounding ecosystems. Since hydraulic fracturing is fairly new and virtually non-existent in the far north, research is sparse and some conclusions are based on investigations in the south. All impacts which target water systems, animals and plants are long term and it is not immediately evident how this will affect entire ecosystems. This paper will only mention some of the immediate impacts. The conclusion will explore how suitable this method is in the North and if other countries had reasonable grounds to impose a moratorium or ban on hydraulic fracturing. Water Quantity Our arctic and sub arctic water systems are characterized by continuous and discontinuous permafrost and lakes to absorb excess water, especially in spring. The sensitivity of these ecosystems relies on patterns like water flow peaks in the early summer with nutrient discharge 2

3 and storage capacities of wetlands. Whitley states that the annual peak flows in spring increase with latitude as the result of the dominating permafrost and reduced water pathways 6. The water volumes of river discharges are greatly dependant on seasonality and annual precipitation patterns. Precipitation patterns are also impacted by climate change. Whitley discusses the developing trend of increasing winter flow for streams in continuous permafrost areas and reduced spring flows due to increased infiltration 6. Monthly flow rate measurements show that the Snake River s (Peel River Watershed) flow rate fluctuates from a minimum of nearly 0m 3 /s and a maximum of approx. 550m 3 /s. 6 Since surface water will be recharged by aquifers, the annual minimum flow in higher latitudes is dependent on available ground water resources 6. According to a CCME report, one of the most common gaps concerning aquifers is the uncertainty regarding groundwater/surface water interactions 3. Overwintering habitats for fish are directly impacted by changes in the groundwater availability due to the connection between surface and subsurface water flow. Responses of groundwater systems are more subtle because the response is usually delayed and of lower magnitude. Shallow aquifers respond faster than deep aquifers, are limited in number to the latter, and easily contaminated 6. Wetlands interact strongly with aquifers in some areas and stream flows that are often sustained by groundwater. In the Yukon our wetlands are habitat for large migrating bird populations and if water resources for wetlands become depleted, these birds would seek different summer habitats if possible. In the Yukon, the withdrawal of a huge volume of surface water may not affect our drinking water resources in the immediate future, but it would have serious implications for our northern, subarctic watersheds. In my opinion, research concerning available groundwater resources and climate change induced flow patterns would have to be conducted for years to produce 3

4 conclusive results. We have to apply a precautionary approach in order to prevent serious water depletion in northern ecosystems as well as amend current legislation to implement stringent regulation on the sustainability of our ground water uses. Water Quality There are two types of wastewater recovered during hydraulic fracturing flowback water and produced water. Flowback refers to the water mixture produced when the fracking procedure is completed, the pressure is released, and the direction of fluid flow reverses. It usually returns at a high flow rate, within two weeks after the well has been fractured, and contains 10-40% of the chemical additives in fracturing fluids and large quantities of naturally occurring constituents. After the fracturing event, the pressure is decreased and the direction of fluid flow is reversed, allowing fracturing fluid and naturally occurring substances to flow to the surface; this mixture of fluids is called flowback. The mixture contains a percentage of the used chemical additives and the flowback period in shale gas reservoirs lasts several weeks 9. Produced water refers to a water mixture that is accompanied by the gas, it flows slowly out of the wellhead and the flow can continue for months or over the life-time of a well site. Flowback and produced water are two types of waste water that can both contain naturally occurring formation water that is thousands of years old. High concentrations of salts, naturally occurring radioactive material (NORM), and other contaminants including arsenic, benzene, and mercury are found in wastewater as result of hydraulic fracturing. The flowback period typically lasts for periods of hours to weeks, although some injected water can continue to be produced along with gas several months after production has started. The amount of fracturing fluid recovered as flowback in shale gas operations ranges from as low as 10% to as high as 90% 1. In 4

5 the Marcellus Shale, about 25 % of the water injected during hydraulic fracturing operations may be produced during flowback 13. There is no clear transition between flowback and produced water because both types of wastewater contain fracturing fluid and naturally occurring materials. Produced water, however, is generated for a longer time period than flowback water. The physical and chemical properties of both types vary with fracturing fluid composition, geographic location, and geological formation. Chesapeake Energy analysis of flowback from various reports shows that concentrations of TDS (Total Dissolved Solids) can range from 5,000 mg/l to more than 150,000 mg/l (slides 21 to 24) 4. The HF Draft Plan 9 (Appendix D) lists hundreds of chemicals that have been identified in the hydraulic fracturing fluid or the wastewater. Flowback water may also contain radionuclides 13 as well as volatile organic compounds (VOC), including benzene, toluene, xylenes, and other chemicals. Several authors have confirmed the occurrence of radionuclides in oil and gas operations 4, 5,10,11,12. The radionuclides identified in oil and gas streams belong to the decay chains of the naturally occurring products of 238 U and 232 Th. These parent radionuclides have very long half-lives and activity levels. They are producing several series of daughter radioisotopes of different elements and of different physical characteristics. Analyses of NORM from many different oil and gas fields show that the solids found in recovered wastewater do not include 238 U and 232 Th. These mother elements are not mobilized during the injection from the reservoir rock that contains the oil, gas and produced water.6.the produced water contains cations of calcium, strontium, barium and radium dissolved from the reservoir rock. As a consequence of the injection process, this water contains the radium isotopes 226 Ra from the 238 U series and 228 Ra and 224 Ra from the 232 Th series 6. Slides 22 and 24 (pages 13 to 16 of this report) of the Chesapeake Energy 4 investigation show how 226 Radium and 228 Radium increase up to 200 hours after hydraulic fracturing 5

6 (western US and eastern US). In both locations 226 Ra has a background radiation before hydraulic stimulation 50 to 100 pci/l and peaks at around 1000 pci/l. 228 Ra is initially measured at approximately 20 pci/l and has a max of 460 in the western US to 620 pci/l in the East. These two radium isotopes are referred to as unsupported because their long lived parents 238 U, and 232 Th and also 228 Th remain in the reservoir. To put in perspective, allowable levels in drinking water are 5pCi/L. According to an article from U.S. Environmental Protection Agency (EPA) in the New York Times the dangers to the environment are greater than imagined 10. Over 179 operating wells are currently producing wastewater with elevated levels of radiation, and at least 116 have reported levels of radium 100 times as high as allowed by federal drinking-water standards. The New York Times found documents from EPA that drilling waste has been accepted at sewage treatment plants without being tested for radioactivity. Sewage treatment plants are generally not equipped to remove radioactive contaminants. EPA and industry researchers claim that the bigger danger of radioactive wastewater is its potential to contaminate drinking water or enter the food chain through fish and farming. Wildlife and fish would be heavily impacted by this type of long term pollution. Over time radioactive particles, especially the ones released by alpha radiation will enter the food chain. Alpha particles don t have the power to penetrate soil surfaces and are stored safely underneath a soil crust. If they are transported to the surface they can be inhaled or ingested by animals, or taken in by fish in the water. Once they enter a body they will be stored in bones or other body tissue or organs. The 226 Ra isotope has a half life of 1600 years. During this time it will continue to emit alpha particles which enter the food chain, and will cause genetic defects or cancer. 6

7 Current practices are to hold flowback and produced water from hydraulic fracturing operations in storage tanks and waste impoundment pits before they are recycled or disposed 9..These pits are supposedly designed for temporary or long-term (e.g., evaporation pits used for treatment) storage. This type of land disposal or even discharge into surface waters without immediate treatment poses huge environmental and legal problems. Even the underground re-injection of wastewater is problematic because of capacity problems and the polluted water has to be transported to the injection site. Finally, one of the most problematic aspects of handling flowback water is the temporary storage and transport of such fluids prior to treatment or disposal. There is always a potential of leaks or spills associated with on-site storage. According to Zoback 13, fluids are often stored in lined or even unlined open evaporation pits. Even if the waste water does not infiltrate directly into the soil, a heavy rain can cause a pit to overflow and create contaminated runoff 13. Another potential source of contamination is the mechanical integrity of the well. If there are problems within the well, flowback and produced water could enter the local aquifers and contaminate local drinking water resources. There are concerns associated with the design, construction, operation, and closure of waste impoundment pits 9. The Yukon regulatory system is currently not equipped to evaluate any radioactive pollution issues since policies have not been developed. Legal problems will arise because radioactive waste should be dealt with according to the Nuclear Safety and Control Act (federal legislation). In my opinion, this type of groundwater pollution needs to be studied extensively and new water treatment methods have to be developed to reclaim the wastewater. The reasons why hydraulic fracturing should not be practiced in the North today are pretty obvious. First and foremost, there is very little empirical scientific data on drilling and risks related to hydraulic fracturing 7

8 available. Northern ecosystems are very sensitive to disturbance, and this technique will practice will cause more disturbance than many other techniques. The greatest impacts we could see from hydraulic fracturing will be on the water systems that have significant variable seasonal flow patterns and within streams that serve as fish overwintering habitats. The fish overwintering habitats are sustained by underground water resources but there no basic data on the location of underground water supplies, faults and flood plains available from the Yukon. In my opinion, radioactive pollution caused by deep drilling (even exploration drilling), is widely underestimated. The Vienna report shows that other nations are more concerned about such impacts. In the Yukon, there is no regulatory system in place to deal with the impacts of hydraulic fracturing, let alone regulations for potential radioactive pollution. We don t even have enough territorial water inspectors to deal with mining infractions, so any newly drafted regulations would not be enforced anyways. Before all these necessary provisions are in place, I think it would be unrealistic to allow any advanced exploration for oil and gas and hydraulic fracturing. References 1 BC Oil and Gas Commission (August 2012). Investigation of observed Seismicity in the Horn River Basin 2 Campbell & Horne (2011). Shale Gas in British Columbia: Risks to B.C. s water resources. The Pembina Institute and The Pembina Foundation 8

9 3 Canadian Council of Ministers of the Environment (CCME). (2010). Review and Assessment of Canadian Groundwater Resources, Management, Current Research Mechanisms and Priorities, PN Chesapeake Energy, Mc Elreath, D. (2012). Comparison of Hydraulic Fracturing Fluids Composition with Produced Formation Water following Fracturing. Powerpoint 5 Howarth, R. Ph.D. et al (2012). Methane Emissions from Natural Gas Systems at Forum on Hydraulic Fracturing 6 International Atomic Energy Agency (IAEA) (2003). Radiation Protection and the Management of Radioactive Waste in the Oil and Gas Industry. Safety Report No. 34 Vienna 7 Kenyon, J. & Whitley, G. (2008). Water Resources Assessment for the Peel Watershed. Whitehorse. ( Whitley ) 8 National Wildlife Federation (2011). No more Drilling in the Dark United States Environmental Protection Agency (2012). DRAFT Hydraulic Fracturing Study Plan February 7, Science Advisory Board Review, Washington, D.C. 10 Urbina, I. (2012). Regulations lax as Gas Wells Tainted Water Hits River, New York Times 11 Veil, J. A. (2008, May 13). Thermal distillation technology for management of produced water and frac flowback water. Water Technology Brief # Prepared for the U.S. Department of Energy, Office of Fossil Energy, National Energy Technology Laboratory, contract no. DE-AC02-06CH Argonne, IL: Argonne National Laboratory. Retrieved Dec2012, from ANL-EVS-evaporation_technologies2.pdf. 9

10 12 Veil, J. A. (2010, July). Final report: Water management technologies used by Marcellus Shale gas producers. Prepared for the U.S. Department of Energy, Retrieved in December 2012, from 13 Zoback, M., Kitasei, S., & Copithorne, B. (2010, July). Addressing the environmental risks from shale gas development. Briefing paper 1. Washington, DC: Worldwatch Institute. Retrieved December 2012, from: 14 Wilson, N. (2002).The Effects of Oil and Gas Industry activity on Fish and Wildlife. Prepared for the Fish and Wildlife Management Board. Picture 1: Graph of producing well 13 10

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