Hydraulic Fracturing: Boon or Bane? MIT Energy and Clean Tech Series Palo Alto, CA 22 January 2014 George E. King

Transcription

1 Hydraulic Fracturing: Boon or Bane? MIT Energy and Clean Tech Series Palo Alto, CA 22 January 2014 George E. King 1

2 Framework Questions 1. How does hydraulic fracturing work? 2. Can chemicals in fracturing fluid contaminate fresh water supplies? 3. Can we recycle all the produced water and other fluids from fracturing? 4. What can prevent methane escaping into the atmosphere? 5. Can fracturing cause earthquakes? 6. How might focusing on the real risks shift the regulatory discussion? 2

3 There are dozens of potential productive shales; however, not every shale can be effectively produced with the same completion. No two shales are exactly alike. Shales of North America 3

4 Large Producers (top 50) Who Does Fracturing? ~ 50% of U.S. Fracs ~ 50% of U.S. Fracs Small Producers (~1500?) Prospect Analysis Leasing & Permits Seismic & Evaluation Drilling Location Exploratory Drilling Development Drilling Pumping Service Providers (Big 5) Pumping Service Providers (mid 10) Pumping Service Providers (~50) ~ 700 frac fleets active Water Supply Trucking Water Transfer Proppant Suppliers Chemical Suppliers Produced Water Treating Tank Suppliers Treated Water Storage HSE equip. Flowback Monitoring Produced Water Re-injection (floods) Operations Pipelines, Refinery, Processing, Distribution, Manufacturing Produced Water Disposal 4

5 Sequence of Events in a Development 5

6 The Fracturing Debate! Massive Cover-Up or Massive Fear-Mongering? Some Truth on Both Sides.. Follow the money & agenda of the position supporters Let s look at a few statements: 1. Fracturing is new!...fracturing is 60 yrs old! 2. Fracturing doesn t pollute.my well has gas in it! 3. Gas emissions are high!...emissions are low! 4. We can frac anywhere! ban fracturing! 5. Water usage is huge!. is 1% to 2% of overall water use! 6. Wells don t leak! some wells do leak! 7. Fracturing causes quakes! no, a few disposal wells did! 8. Fracs pollute groundwater! there are no traces of frac water 6

7 Two Well, Two Frac Fleets, Single Pad Operation 12 to 20 fracs in 3 to 5 days total. 10 to 20 supply trucks support each frac operation. Courtesy of Baker Hughes 7

8 Fracturing Uses Hydraulic Pressure to Create Cracks in the formation or open cracks already there 8

9 Fracturing Fluids What are they? What is the Risk? Slick Water Fluids salt or fresh water with friction reducer & biocide. 0.05% to 0.2% total additives. Risk level v. low chemically, fractures are small Hybrid or Gelled Fracs salt or fresh water with polymer, x-linker, biocide, acid, scale inhibitor, breaker, etc to 0.1% additives. Risk level low chemically, fractures wider, taller & longer. 9

10 Common Chemicals Used in Slick Water Fracturing ( reported on ) Most Common Frac Additives Friction Reducer Composition CAS Number Total amt. in avg frac (10k bbl) Polyacrylamide to 200 gallons. Used in recycled water? 50k to 70k ppm is upper limit Alternate Use baby diapers, floc for drink water Biocide Glutaraldehyde 50 to 100 gallons. decrease w/ increasing salinity Alternate Biocide Scale Inhibitor (if needed) Gellants (hybrid / gel) Ozone, Chlorine dioxide UV, Phosphonate & polymers Guar & Cellulose & others 10 to 100+ gallons depends on local Depends on frac type ~1000 to 2000 lb. Turbidity & v. high salinity hindrances. Specific ions like calcium are a problem. Ca ++, Fe x & TDS problem. Medical disinfectant Disinfectant in municipal water Some cleaners and medical treatment Thickening ice cream / soup Acid 5% TO 15% hydrochloric ~0 to 2000 gals not universally Yes food prep, mfg, swim pools, Acid Corrosion inhib. Quat. Ammonium salts, Coa Coa Amines, etc. Various 2 to 40 gals if acid is used Yes Industrial 10

11 Science Matters and Lowers Risk Even in the Barnett Core, there are areas (green) that are highly productive and areas that are poor (red). Shale characteristics, operator expertise, the technology of the time, the cost of D&C and the value of gas are the primary factors. These sweet spots are the targets of the most technologically advanced companies. Reducing wells drilled in poor areas also reduced risk. Modified from Barnett Shale Report 11

12 First example in 1974, in use offshore since mid 1950 s 12

13 Horn River 6000 acres accessed from a 6 acre pad Slide Source Brad Affleck - Apache 13

14 Vertical Fractures where do they Fractures are naturally limited: 1. Natural formation barriers. 2. Stresses in the rock. 3. Leakoff limits height growth. 4. Natural fracture network. stop? Typical effective frac height 300 ft. Microseismic can be a frac height indicator but also influenced by rock-to-rock stresses. Two inch by 1.5 view from a downhole TV camera run in clear water. Amoco - Circa

15 Microseismic Fracture Monitoring What does MS do? What does it cost? How reliable is it? 15

16 How Close Does the Top of a Frac Come to Ground Water? 16

17 Unconventional Hydrocarbons & Fracturing First Shale Gas; Now Flowable Shale & Tight Oil Spectacular reserves and production increases HOWEVER; a lot of oil is left behind after the 4+ year average well life. How can liquid production be enhanced in low permeability formations. 17

18 How is shale production sometimes different? 7 Peak Production second month % to 70% decline in first year driven by shale and completion type % Decline in 2 nd year 6% to 15% decline in 3 rd Slight uptick in production possible through desorption in some cases Months on Production 18

19 What are Common Groundwater Pollutants? Slide 19 UST Gas & Diesel Septic Systems Landfills Spills Fertilizer Large Industrial Facilities Hazardous Waste Sites Animal Feedlots Pesticides Surface Impoundments Storage Tanks surface Urban Runoff Salt Water Intrusion Mine Drainage Agriculture Chem. Facilities Pipelines & Sewer Shallow Inj. Wells Salt Storage & Road Salting Land application of Waste Irrigation Practices EPA, 2000 Oil and Gas Wells Didn t Make the List.

20 Slide 20 What are Groundwater Pollutants Today & Where do Oil & Gas Wells Rank? Used Texas as a Study Case. Over a million penetrations through the 29 major & minor aquifers in Texas. Texas is #2 in total Groundwater withdrawals with ~ 80% going to Agriculture & Municipalities. If the water was really polluted by O&G wells, we d see it quickly in Municipal & Ag. SPE , Barrier vs. Well Failure, King

21 Last 12 years of Pollution Reports in Texas Top 20 Listed - TCEQ & TGPC Database Slide 21 Number of New Reports Per Year SPE , Barrier vs. Well Failure, King

22 Allocation of Texas TCEQ Pollution Claim Frequency Producing Wells are less than 1% of total for most years. SPE , Barrier vs. Well Failure, King

23 The Potential For Pollution is Reduced by Application of Technology. ERA of Well Construction is More Important Than Age of the Well. Time Era Operation Norms - Level of Technology Era Potential For Pollution 1830 to 1916 Cable Tool drilling, no cement, wells vented High 1916 to 1970 Cementing isolation steadily improving. Moderate 1930 s Rotary drilling replace cable tool, BOPs Moderate & Lower 1952 Fracs reduce # wells. Better pipe & cement Lower from Frac aspects 1960 Gas tight couplings and joint make up Moderate 1970 Cement improving, Horizontal Wells introduced Lower 1988 Multi-frac, horizontal wells, pad drilling Lower reducing environmental land footprint 90% 2005 Well integrity assessment, premium couplings, adding barriers & cementing full strings. Lower after 2008 to 2010 (STRONGER Reg Review) 2008 Chemical toxicity & endocrine disruptors Lowest yet, most states sharply reduced. Real time well integrity needs caught up with design and studied - early warning & avoidance. inspection requirements. 23

24 How Much Water is Used? How Much is Recovered? What is in it? Area Typical total frac vol (gal) (all fracs total in one well) % of initial load water recovered after the frac Typical Total Added Chem % in Frac Vol (V/V) Added chemicals -% in Flowback (gross estimates) Barnett (Texas) 3 to 4 million 30 to 50% 0.2% <0.05% Devonian (Marcellus - PA) Eagle Ford (Texas) Fayetteville (Arkansas) Haynesville (Texas & LA) 4 to 5 million 40 to 50% 0.2% <0.1% 4 to 5 million 5 to 15% 0.3 to 0.5% (hybrid fracs) 3 to 4 million 30% to 60% 0.2% <0.05% 4 to 6 million 5 to 10% 0.3% (hybrid fracs common) Woodford (OK) 4 to 5 million 30 to 50% 0.2% <0.05% <0.2% (polymer dominated) <0.1% (polymer dominated) 24

25 Water Use & Re-Use 1. What & where are water sources? 2. Can we avoid using fresh water? 3. N.O.R.M. potential is it a problem? 4. Disposal Issues. Source: Susan Combs, Texas Comptroller of Public Accounts: The Impact 25 of the 2011 Drought and Beyond, February 6, 2012.

26 How Fast Is the Water Recovered? 15 days 10 to 20 years 26

27 Water rate 1000 to 3000 bbl/day Water Rate 10 to 1000 bbl/day Water Rate 0 to 30 bbl/day Gas Tracking Early Water Backflow 1 to 5 days 1 to 4 weeks > 4 weeks

28 Methane Seepage from Soils Oil & Gas Seeps are indicators of oil & gas beneath the surface Many natural seep flows diminished as wells were drilled & produced. SPE , Barrier vs. Well Failure, King

29 Gas migration >>200+ yrs. old, highly regional, many causes, 1000 s of seeps. SPE , Barrier vs. Well Failure, King

30 Comparing Spills and Seeps Various sources data in SPE Lakeview Gusher, CA Onshore, 1910 Santa Barbara Blowout, CA, 1969 Tanker Grounding, MA, 1976 Tanker Grounding, AK, 1989 Tanker Grounding, TX, 1990 Sabotage, Kuwait, 1992 Tanker Grounding, LA, 2000 Pipelines Ruptured by Hurricanes, Barge Collision, LA, 2008 Tanker Collision, TX, 2010 Pipeline Corrosion, MI, 2010 Macondo Blowout, GOM, 2010 Natural Seeps, Coal Point, CA, Yearly Natural Seeps, GOM, Yearly 1,000 10,000 BARRELS 100,000 Single Estimate High Value Range 1,000,000 10,000,000

31 Well Construction What s Different? 1/27/

32 Barrier and Integrity Failures: >330,000 US wells Barrier or Integrity Fail Texas Horizontal Integrity Failure Texas Newer Wells Barrier Failure Texas Newer Wells Integrity Failure Texas Old Wells Barrier Failure Texas Old Wells Integrity Failure Ohio Newer Wells Barrier Failure Ohio Newer Wells Integrity Failure Ohio Old Wells Barrier Failure Ohio Old Wells 16,000 horizontal multi-frac wells no subsurface leaks reported or found. Older well data often skewed by lack of barrier & integrity differentiation % 0.020% 0.040% 0.060% 0.080% 0.100% Things That Keep Real Integrity Failures Very Low 1. Pressure inside the wells is lower than outside in hydrostatic of water table. 2. Modern wells are built with multiple barriers. 3. Cement reinforces and protects the casing. 4. Regulations are tighter now than 3 years ago. 5. Multi-Fractured horizontal wells replace 5 to 10 vertical wells in shale. Less pollution potential with fewer water table penetrations. What Proves it? rankings of proven groundwater pollutants. 32

33 Failure Factors Recognized: Type of Well Full Details in SPE Maintenance Culture Era of Construction Geographical Location Age of Well Design & Construction Usage Change 33

34 Does Fracturing Create Earthquakes? 34

35 Red Flags to the Community Trucking congestion, accidents, road damage. Chemicals unidentified, misidentified, no info. Perception of high water usage Influx of workers Spills Lack of contact from the developers! Hysteria Sources: Bloggers, slanted university studies documentaries some environmentalists, media, rumor mills, 35

36 Regulations Effective or Development Preventers? Effective & Development Encouragers Standards reduce real risks Consistent operations by all operators Encourages produced water reuse instead of disposal. Provides a level field for well development. Requires reporting of all fracs to public available site ( Development Preventers Prevents Any Development Every well a target for environmental impact and endless public challenge. Creates unachievable goals or excessive cost to comply. Continues to make companies prove a negative regardless of a individual performance record. 36

37 Questions I would ask. 1. Will everything be on 2. Minimum distance - -water to frac be > 1500 ft? 3. Will green completions be used? 4. Can multi-well pads be used? 5. Does the company have a list of chemicals they will not use? 37

38 So What are risks to groundwater by oil & gas activities? Major Risk Poor performance by the few. Lack of effective maintenance. Moderate Risk Transport & on-site storage Minor Risks Drilling phases (generally not on shales: low perm) Well construction (early) & older era or vintage wells. Thread leaks (connections) Poor cementing practices Near zero risks Cement in producing wells The specific act of fracturing rock 38

39 Can & Should Every Well be Fractured? No. Some wells don t need fracturing. Some wells cannot be fractured safely. Some geology makes gas migration more likely. Rules of Thumb: Fracturing in deeper wells poses less risk (>2000 ft). Stand off from bottom of fresh water ~1000 ft (safety factor varies). Need two cemented barriers between fluid flow path & fresh water. Fracturing in older wells is higher risk (test & derate max. pressure?). Well construction best practices are required. A pop-off or pressure release valve is good insurance. Set below the minimum burst pressure of the pipe. A line from the valve to a tank prevents spills in event of a over-pressure. Odds against a pipe rupture are about 50,000:1 to 100,000:1. Areas with gas seeps & historical near-surface gas more likely to see gas migration before & after well development. 39

40 Reducing the Impact of Shale Gas Development is Critical Questions? More Information at Restored shale drilling site - Chesapeake 40

41 Reference Slides not in the regular presentation 41

42 Risk = Frequency of Occurrence vs. Impact Slide 42 Risk exists in every action. What is operationally safe? Occurrence & impact create a threat level that we can understand & accept or reject based on what we believe: hopefully on assessment of facts. What does the public think is safe? SPE , Barrier vs. Well Failure, King

43 Development by Vertical or Horizontal Wells? 9+ sq. mile area (6000 acres) Horizontal well advantages: 6000 acres: Items Vertical Wells Horizontal Well Pad Wells (80 acre spacing) Roads (miles) 28 2 Gas/Oil Pipelines (miles) 30 4 Frac Water supply pipeline (miles) 30 2 Facility Pads 8 1 Trucking Miles (on pad) (or 1400 with water pipeline) Rig Mob/De-Mob 75 1 Fresh water monitor area 6000 acres 8 acres Pad Footprint (acres) Total Development Footprint 566 acres 45 Total Production Footprint 491 acres 33 Less land used Agreed on pad placement Less traffic, Less dust, Less urban / wildlife disturbance, Less air pollution. All wells penetrate the ground in the same area can be easily monitored Sharply lower methane vapor loss (low press capture and compression) 43

44 HRB Pad Completions: Surface Layout Sand System HP Frac Manifold Debolt Water Pipeline Automated Refueling System Acid Pumping Kit Wellheads GORV MCC Pumpdown Kit Slick-Cable Trucks CT Pumpers P Tank(s) Facility Installation Over 100 people on site 24/7 Layout has many improvements over d-70-k 44

45 Barrier Failure or Well Integrity Failure Single Barrier Failure => No Leak Path? => No Well Integrity Failure Unless All Barriers Fail, A Leak Will Not Happen Wells are Designed with Multiple Barriers. Number of Barriers Depends on the Hazard Level. ZONE Above Surface Fresh Water Hazard to Ground Water If Well Integrity Is Lost Typical Number of Barriers Low 1 to 2 Low to Moderate 2 to 4 Mid Depth Very Low 1 to 2 Deep Lowest 1 45

46 How Much Cement is Needed for Isolation? Every inch of cement is NOT required to be perfect. Slide 46 Quality of cement is more important than the volume. Over 10,000 psi can be held with less than 50 ft of cement, but 200 to 300 ft is routinely used. Isolation can only be measured with a pressure test. Bond logs are not always best tool ~10% channels missed. Instances of false negatives. SPE , Barrier vs. Well Failure, King

47 Fracturing Risk Evaluation => Very Small Risks To Groundwater Frac to Surface? Less than 1 chance in a million Frac Ruptures Surf Csg? Less than 1 chance in 100,000 Earth Quake > 5.0 Less than 1 chance in a million Spills Diesel at surface About 1 chance in 10,000? Highest Risks are Transport, Some from Well Construction Full Details in SPE Spill clean fresh or salt water 2.Spill biocide 3.Spill dry additives 4.Spill of diesel from truck wreck 5.Spill of diesel -wrecked re-fueler 6.Spill frac tank water, no adds 7.Spill frac tank water w/adds 8.Spill diesel fuel while re-fueling 9.Spill of frac tank -flowback water 10. Frac press ruptures surface casing 11. Cooling pulls tubing out of packer (casing maintains integrity) 12. Mud channel, well < 2000 ft 13. Mud channel, well > 2000 ft 14. Intersects well in the pay zone 15. Intersect properly abandoned well 16. Intersects improper abandoned well 17. Frac to surface through rock, well greater than 2000 ft deep. 18. Earthquake, mag. > Frac intersects a natural seep 20. Emissions > background 21. Normal frac operation no problems. 47

48 Impact BD = Biodegradable, NBD = Not Biodegradable, BA = bioaccumable, TOX = Toxic, LTOX = Less Toxic (diluted to safe), SS = subsurface, SUR = Surface, G = Greener or Non Toxic, NR = Not Recoverable, RC = recoverable, AMD = Acid Mine Drainage Severity (high - low) Severity Description Type Extent Volume Lost (gal) Analogous Situation 10 TOX, NBD, BA, SS, NR? > 1 mile >> millions SS & SUR, AMD, NR, NBD, BA 9 TOX, NBD, SS, NR? 100 to 1 mile > 1 million AMD, NR, NBD 8 TOX, NBD, NR, SUR Spill/Leak > 1 mile <100,000 Diluted AMD -overflow 7 TOX, NBD, NR, SUR Spill/Leak 100 to 1 mile <22,000 Diluted AMD 6 TOX, NBD, partly RC Wreck < 100 <10,000 Transport wreck-diesel fuel 5 LTOX, BD, Partly RC Wreck < 100 <10,000 Spill of fertilizer or ammonia 4 LTOX or BD Leak/Seep < 100 <5000 Similar to salt on winter roads 3 LTOX or BD, G, Leak/Seep < 500 <5000 < Treated sewage seep 2 BD or G, Spill >500 <25,000 Similar to draining swimming pool on grass 1 G Leak <10 ft < 5 Food grade chemical, dumping a pot of coffee. 48

49 Is Slick Water Fracturing (SWF) New? Is it a Risk? SWF tried in 1950 s- couldn t carry high proppant loads needed for oil zones. SWF tried in 1980 s -could not compete with gelled water fracturing for gas in sandstones. SWF found niche in shale: low viscosity fluid could penetrate & open natural fractures SWF carries less chemicals & creates less fracture height & length than conventional gelled fracs. Risk is actually lower than conventional fluids. 49

50 Fracs Self-Limited by Frac Fluid Leakoff Take the previous fracture: with 2 wings (each side of the wellbore) and 2 formation faces exposed to leakoff along the frac. The area is 650 x 95 x 2 x 2 = 247,000 ft 2 At a high pump rate (100 bbl/minute), the water injected would be 0.29 ounces per minute per ft 2 of formation area. If the leakoff into the matrix or the natural fractures is more than this, the frac will stop growing. 50

51 Area Proven Another Way - % of Produced Fluids Leaked From Production Leaks and Spills US Gulf of Mexico US Gulf of Mexico Number of Wells 11,498 (3542 active Type of Wells Platform based wells 4,099 Shoe test failures required repair Barrier Failure Freq. Range (w/ containment) 30% overall first annulus SCP 50% of cases. 90% of strings w/ SCP have less than 1000 psi. 10% are more serious form of SCP (Wojtanowicz, 2012) 12% to 18% require cement repair to continue drilling Norway 406 offshore 18% 0 GOM /Trinidad Matagorda Island 623 All Sources in SPE , Barrier vs. Well Failure, King, 2013 Integrity Failure (leak path in or out) Slide % to 0.05% of wells leaked % to % based on produced oil spilled 1980 thru (all repaired before resuming drilling) 2,120 Sand Control 0.5 to 1% 0% subterranean ~0.0001% via surface erosion potential 17 Compaction failures; casing shear & sand fail Sumatera 175 without maintenance 80% to 100% - the high number is due to high pressure and formation compaction. 43% 1 to 4% Wells routinely shut-in and repaired prior to restart.

52 Does Fracturing with Fresh Water Remove Water from the Earth s Hydrological Cycle? Average gas shale frac uses 5,000,000 gallons of water (salt water is replacing some fresh water as fracturing fluid). When methane is burned as a fuel: CH 4 + 2O 2 => CO 2 = 2H 2 O 100,000 BTU of methane => 9.41 lb of water 100,000 BTU (methane) = 100 scf of methane 1 mmscf of methane produces [(1,000,000/100 * 9.41)/8.33 lb/gal] = 11,300 gal 1 bcf produces 11,300,000 gallons of fresh water Gas shale wells produce 1 to 10+ bcf over their lifetime. Methane may be far from the well when burned, so the water is released in a different area. 52

53 Is Fracturing Really New? Multi-faceted answer.. The physics of fracturing has not changed significantly since the early 1950 s. The first multi-fractured wells were prior to The first multi-fractured deviated well was The first multi-fractured horizontal shale well was 1988 (a US DOE funded experiment & DOE-written paper series). First 1 million wells were fractured between 1952 and First 1 million fractures in horizontal wells done 1974 to Fracturing is an evolving technology just as medicine, flight, construction, manufacturing, cars, are evolving technologies. Fracturing is safer today because of advances in green chemistry, well design, monitoring ability, water treating, 3-D seismic and general safety training. 53

54 Can Fracturing Produce Dangerous Seismic Energy? Thousands of fracture treatments, monitored by microseismic, in six different shales, document the fact that energy levels produced by fracturing, even fracturing into local faults, do not approach the energy level needed for damage producing earthquakes or even felt earthquakes of 3.0 moment magnitude or higher. Energy levels for fracturing seismic events are one million to one billion times lower than a damaging quake. 54

55 Rate Effects Different Shales Injected Volume Different Shales 55

56 Injected Volume Different Shales There is not trend of moment magnitude with injected volumes. Like the injection rate, engagement of even very small volumes of fluid with small, local faults within the pay zone result in higher moment magnitude. 56

57 Geological Hazards Karsts sink holes Faults Natural fractures Pinchout of bottom frac barrier Mineral changes Shale thinning 57

58 Faulted zone showing continuity disturbance in the pay. XTO 58

59 Earthquakes ~7 quakes / day felt in U.S. Small quakes are common & swarms of 20,000 in a few months triggered by plate movements. Most of the highest mag quakes predate shale developments & frac invention. For a damaging quake (6.0 or higher), stresses rip 100 s of miles of major faults. Major quake depths are 2 to 7 miles beneath the surface. State Magnitude Date Alaska Arkansas California California Colorado Louisiana Montana N Mexico New York N. Dakota Ohio Oklahoma Pa Tx Virginia W. Virginia Wyoming

60 Frac Flowback Water Treating Some Potential Options and Cost Level Estimates Treatment Method Salinity Reduced Bacteria Control Iron Reduce Calcium & Mg Red. Barium & H. Metal Red. Organic Reduced TSS Reduced Bromine Reduced NORM Reduced Pretreat? All-in Cost Reject or Waste Vol Act. Carbon No No No No No Yes? No No Some Low Mod Biological No Yes? No No Yes? No No Yes Low Low Bleach (Cl - ) No Yes? No No Possible?? No No Low Low Chem. Add. Slight Yes Yes Yes Yes Yes Yes Possible? Some Mod Mod/High Chlorine Dioxide Yes Slight No? Yes Slight No? No Low Low Distillation Yes Yes Yes Yes Yes Yes Yes Yes? Some High High (EC) Elec Coag. Slight? Some? Some? Yes No? Yes Mod Mod (ED) Electro Dial. Slight Yes Possible Possible Possible Possible Yes?? No M/H High Pond/Tower Evap Conc. waste Some Conc. waste Conc. waste Conc. waste Depends Conc. waste Conc. waste Conc. waste No L/M Mod Filtration Macro No No No No No? Yes No? Some Low Mod Filtration Micro No Some???? Yes No? Yes M/H Mod/High Filtration Nano Some Yes Some Some Some Yes Yes No? Yes High High Flocculation? Slight Possible Possible Possible Possible Yes?? Some L/M Mod Flotation? Possible Slight No? Yes Yes No? No L/M Low/Mod Hydro Cyclone No No No No No No Some No No No Low Mod Forward Possible Possible Yes Yes Yes Yes Yes? Conc. Yes Mod Mod Osmosis Ion Exch. Possible Yes Yes Yes? Possible Yes No Yes Low Low Ozone No Yes Possible No No Yes Slight?? No L/M Low Precip Rx. slight Yes Yes Yes Possible Yes Possible Conc? M/H Low/Mod Reverse Osmosis Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes M/H High Sand Filter No Slight No No No Slight Yes No No Some Low Low UV Treat No Yes No No No No No No No Some Mod Low Vacuum Distil. Yes Yes Yes Yes Yes Yes Yes Yes Conc. Yes High Mod/High 60

61 Technology Drivers for shale fracs 61

62 Water Use Per Energy Produced Water used and water consumed are different values. Does fracturing take water out of the hydrological cycle when produced waters (including frac flowback) are re-injected? 62

63 Using Technology: Frac Monitoring Frac Monitoring Technique Frac Loc. in Well Frac Direction Methods Frac Height Frac Length Investigation Timing Surface Pressure No No Indirect No Real Time Downhole Pressure No No Indirect No Post Frac or Real Time Comments More accurate than surface pressure Fiber optic, (temp, Yes No No No Real Time Run on casing press, sound) Microseismic Yes Yes Yes Yes 5 min. delay Tilt Meters Yes Yes Yes Yes 5 min. delay Temperature Logging Yes No Vert. wells No Post frac Vert. Wells Tracer Tagged Proppant Yes Transverse or longitudinal Only in vertical No Post Frac Investigation to a few inches Chemical Tracers in No No No No Post Frac Tag water or oil frac fluid Production Log Yes No Only in No Post Frac Vertical Pressure Build Up, Production Tests & Interference tests No Indirect Indirect Indirect Post Production 63

64 Is Fracturing Exempt from Regulations? No every state has regulations on well construction and fracturing based on local geology, politics and geography of development area. EPA multi-year study changed designation of oilfield produced water to a class II disposal waste stream - overwhelmingly salt water - did not contain significant toxic materials as did class I disposal well waste streams exemption of fracturing from drinking water act appears to be made based on similar thinking. Fracturing is a short-lived event with chemical component 0.1% to 0.5% in fresh or salt water. Time of an fracturing job is 2 to 4 hours & new wells are the overwhelming target. Class I disposal well injection goes on at high pressures for years with concentrated chemicals. No scientifically documented case exists of deep well fracturing growing into fresh water. A few cases are recorded when fracturing ruptured the casing at or near fresh water sands. A few other cases exist where a small amount of fluid channeled along the poor cement and contacted a water zone. 64

65 Produced Water Recycle Pilot (Newfield) Net cover not visible but it is there. Courtesy Newfield Energy 65

66 A Few Water Recycle Learnings To be economic, a water project may need: >50 active wells or large water flood & water handling system. A steady frac campaign A standby source of brine and/or fresh water backup Treat water to minimum level for re-use don t gold plate [Bio-control, H2S removal, some TSS removal, ions? => use]. Innovative treating approaches avoid high cost solutions. Maximize pipeline transfer of all water streams. Standby disposal well. Adequate storage & separate storage facilities Special sites for large, temporary, above-ground holding tanks. 66

67 Definitions & Highest Risk Areas Fracturing Operations Transport / Storage water(s) Transport / Storage of sand Transport / Storage chemicals Pumping fracture treatment First two weeks production Later production of fluid Rough Risks Truck accidents, spills Truck accidents, dust Accidents, spills, toxins? Pipe breaks, leaks Transport, disposal Leaks, storage, recycle Definition Confusion: To the oil industry, fracturing is the process of breaking rock. To the public, fracturing is the entirety of well development. 67

68 Negatives for Large Scale Well Developments Well development can be a traffic nightmare in urban environments. Road damage is significant in areas with roads not meant for industrial use. Dust, noise, spills, wrecks, soil disturbance & people activities increase during development Areas not accustomed to oil & gas developments usually lack infrastructure to minimize many of the large well development problems. 68