Recommended Practices Associated with Hydraulic Fracturing Operations

Transcription

1 Recommended Practices Associated with Hydraulic Fracturing Operations

2 API standards program includes best-practices for hydraulic fracturing which include: Proper well construction and integrity Zonal isolation through casing, cementing and mechanical barriers Water management and disposal Mitigating surface impacts Overall site management Good neighbor performance

3 Documents API Recommended Practice 51R - Environmental Protection for Onshore Oil and Gas Production Operations API HF-1 Hydraulic Fracturing Operations Well Construction and Integrity Guidelines

4 Documents API HF 2 Water Management Associated With Hydraulic Fracturing API HF-3 Surface Impacts API Standard 65-2 Isolating Flow Zones During Well Construction

5 Overview The goal of the documents is to present development plans and programs for overall operations from site development, drilling and well construction, completion and production and finally abandonment. The documents attempt to identify risks and industry best practices to mitigate those risks.

6 Overview By their nature, there is overlap between the various documents. While they can be used as stand alone documents, they are also applicable as a package of related standards.

7 Presentation Plan Discussion will present each document and highlight some of the more significant areas found in each. Copies of API documents will be available following the presentations. Also available through API website at:

8 API RP 51 R Environmental Protection for Onshore Oil and Gas Production Operations

9 API RP 51 R - Background Provides recommendations for environmentally sound practices for onshore oil and gas drilling and production operations. Covers all aspects of E&P operations from exploration to decommissioning. Applicable to Contractors and Operators. Revised to include hydraulic fracturing operations. First issued in the early 1970 s

10 7 Key Activity Areas Government agency roles Lease road and site location and construction Drilling and production operations Flowline and gathering systems Produced water and waste management practices Decommissioning and site reclamation Good neighbor practices

11 Government Agencies Ensure all permits are obtained All operations conducted as per local, state and federal requirements Minimize impacts to existing land uses

12 Lease Roads Planning Design and construction Use of primitive or overland routes Maintenance Public roads Lease/private roads Decommissioning and reclamation

13 Production and Injection Wells Planning Construction considerations to include site preparation, equipment selection, well operations and waste management Full life cycle approach for all wells Well Drilling and completion Testing & Operations Well Abandonment

14 Flowlines and Gathering Lines Addresses all gathering and system lines, including electrical systems Consider impact of construction and maintenance on people, animals, plants and the land, both surface and shallow subsurface Practices address: Route Selection Operation Decommissioning Construction Maintenance

15 Production Facilities Basis of design and operation is to minimize adverse effects on the environment. Impacts on local population, land, surface and subsurface waters, air quality and animal and plant species, including habitat, should be considered. Includes detailed guidance on: Site selection Construction Operation & Maintenance Facility design Training & Inspection

16 Good Neighbor Guidance Objectives Protect public safety Protect the environment Respect property rights of all neighbors Communicate

17 API RP 51 R Overview document that contains recommendations for environmentally sound practices. Covers all aspects of E&P operations.

18 API HF 1 Hydraulic Fracturing Operations Well Construction and Integrity Guidelines

19 Scope Provide guidance and highlight industry recommended practices for well construction and integrity for wells that will be hydraulically fractured. Well integrity Isolate the internal conduit of the well from the surface and subsurface environment Isolate and contain the well's produced fluid in a production conduit within the well. 19

20 General Principles Protect groundwater and the environment Combination of steel casing and cement sheaths, mechanical isolation devices Well design and construction Goal is to ensure environmentally sound, safe production of hydrocarbons Drilling and completion process Cycles: drilling, running casing, cementing, perforating, fracturing, etc. 20

21 Casing Selection Design and selection of utmost importance Must withstand anticipated forces, and pressures etc. Casing standards - API Spec 5CT Design, manufacturing, testing and transportation 21

22 Cementing Cement / Material Selection Placement for complete zonal isolation Good cementing practices Planning Design Execution Evaluation 22

23 Well Construction Guidelines Generally consists of four components: Conductor casing Isolate shallow groundwater Surface casing Isolate groundwater aquifers Intermediate casing Isolate subsurface formations Production casing Isolate production zone from other formations Contain hydraulic fracturing, production strings, etc. 23

24 Well Construction Guidelines Horizontal wells Improve performance Fewer wells for same resource Well can still contain conductor, surface and intermediate casing strings Production casing goal is the same as for a vertical well 24

25 Well Logging and Other Testing Data gathering tools for formation evaluation, well design and construction. Open-hole logging Locate and evaluate hydrocarbon producing formations Cement integrity (Cased-hole Logging) Full evaluation requires supporting data Drilling reports, drilling fluids reports, cementing reports, caliper logs etc. 25

26 Well Operations Well Construction Perforating Fracturing Process Equipment and materials Data gathering, analysis and monitoring 26

27 Well Construction Contains guidance on: Material Selection Performance Requirements Evaluation Recommendations Construct a wellbore that has complete formation isolation

28 Perforating Holes created through casing into production formation Jet perforating guns loaded with specialized charges Create tunnels isolated by the cement sheath 28

29 Hydraulic Fracturing First used in 1947 The use of fluid and pressure to crack the rock to create a pathway to the wellbore Includes the placement of small granular solids (proppant) into the pathway to ensure it remains open Objective: Improve production rate Increase the economically recoverable reserves for a well 29

30 Hydraulic Fracturing Horizontal fractures May occur at depths less than 2,000 ft Vertical fractures Overburden stress increases with depth Vertical stress becomes dominant Least Principal Stress is in the Vertical Direction Resulting in a Horizontal Fracture Least Principal Stress in the Horizontal Direction, Vertical Fracture 30

31 Hydraulic Fracturing Hydraulic Fracturing Process Production string cemented/perforated Apply hydraulic fracturing pressures Frac strings may be needed Frac Stages: Pad, proppant stages, displacement Monitor pumping psi, rates, etc. Analyze data and adjust as required Track volumes pumped Wait for fluid viscosity "break" Flow well to recover fluids Production test the well 31

32 Hydraulic Fracturing Equipment Fluid storage tanks Proppant transports Blending equipment Pumping equipment Monitoring and control Sensors Data collection Frac van 32

33 Depth (ft) Frac Job Depth Mapping Marcellus Mapped Frac Treatments - Ohio and Pennsylvania Deepest Aquifer Depth fractop 2000 perftop Frac stages (sorted on Perf Midpoint)

34 Monitoring Frac Geometry Microseismic Fracture Mapping Enables understanding and controlling where the fractures are located Helps maximize stimulated reservoir volume

35 Contribution of Shale Gas Development Source: EIA Annual Energy Outlook 2011

36 Questions? Acknowledgements: Ron Sweatman, Halliburton

37 HF-2 Water Management Associated With Hydraulic Fracturing 1st Edition, June 2010

38 Overview of HF-2 Scope of the HF-2 Document API s drivers for developing a Water Management Guidance Document Overview of the HF-2 Guidance Document Key takeaways Examples in which operators are implementing the HF-2 recommended practices

39 Scope of HF-2 Identify and describe current industry best practices used to minimize environmental and societal impacts associated with the acquisition, use, management, treatment and disposal of water and other fluids associated with the process of hydraulic fracturing.

40 Water Management Associated with HF Since 2006, resource base in the US increased from 1,321 to 1,898 Tcf (44% increase)

41 Influence Driving HF-2 EPA s Draft HF Study Plan took a full water cycle approach Including: Water acquisition, chemical mixing/site management, well construction, injection/fracturing, flowback and produced water management, and wastewater treatment and disposal SEAB Recommendations concerning water use and management The Subcommittee urges adoption of a systems approach to water management based on consistent measurement and public disclosure of the flow and composition of water at every stage of the shale gas production process

42 HF-2 Key Issues Water Use and Management Associated with Hydraulic Fracturing Planning Considerations Water Management Drivers Obtaining Water Supply For Hydraulic Fracturing Evaluating Source Water Requirements Fluid Handling And Storage Considerations Water Management And Disposal Municipal & Industrial Waste Water Treatment Facilities Flow Back Water Recycling/Reuse Injection Wells

43 Fluid Requirements for Successful HF Requirements are the result of: Geology The operating environment The fracture design The type of well drilled The choice of the fracturing fluid selected will dictate the design, types of additives required, the fate and transport of these fluids and ultimately how these fluids will need to be managed

44 Factors Influencing HF Fluid Composition Functionality in the wellbore Formation properties and composition Material selection Should be optimized for each formation The additives generally comprise 0.5 1% of the total HF fluid Operators should strive to minimize their overall use of fracturing additives while maximizing their use of environmentally benign solutions

45 Water Planning Considerations Water Acquisition Transportation - Movement from source to well site and to point of treatment or disposal Storage - Requirements and constraints for water storage Use How will the water be used and volume required Treatment and Reuse/Recycle Disposal

46 Evaluating Source Water Requirements When entering a basin, Operators should conduct a comprehensive evaluation of cumulative water demand on a program basis Review should include: The timing, logistics and accessibility of source water needs Adequacy of source waters (volume and quality) Water Sources: Surface water Municipal water supplies Groundwater Treated wastewater Recycled produced water and/or flowback water

47 Surface Water Use Operators should consider the following potential impacts when evaluating the use of surface waters: Timing and location of withdrawals Especially during low-flow periods, droughts, and times of competing demands (ex: irrigation for agricultural purposes) Ownership, allocation, or appropriation of water resources Required permitting from local, state or multi-state agencies Impacts to downstream habitats and users (including fish & wildlife)

48 Transportation Considerations Distribution via surface lines Water supply and management should consider the constraints associate with fluid transport Trucking can present issues in urban areas Evaluate the use of temporary surface pipelines to transfer water Use of multi-well pads increases efficiency while minimizing truck traffic - allows for centralized management of flowback water

49 Disposal Water used in the HF process is generally disposed of in one of three ways depending on area requirements: Reused / Recycled Delivered to treatment facilities Injected in permitted disposal wells Selection of disposal option is based on a variety of factors, including: Flowback water quantity and quality characteristics Regulatory considerations Resource economics

50 Water Management Program Examples

51 Marcellus Shale Surface Water Acquisition & Storage 100% Reuse in the Marcellus Store surface water in engineered, lined impoundments Remote Level Monitoring System Timing of withdrawal Volumes of withdrawal Security fencing Dilution of flowback with freshwater Simple filtration and/or clarification Minimizes Trucking

52 Williams Piceance Basin Centralized HF Operations Williams implements centralized impoundments in the Piceance Basin, and they also employ centralized HF operations Involves placing the fracturing equipment in a central location f equipment can pump fracturing fluids to wells on multiple well pads The equipment on one location has fractured as many as 140 wells Reduces surface disturbance, minimizes freshwater use, and reduces truck traffic

53 EnCana Piceance Basin Recycling and Pipeline Infrastructure since 2003 Extensive water treatment and distribution system for all drilling and well completion operations in Colorado's Piceance Basin Facilities designed to treat and recycle about 45,000 barrels of produced water per day. Continue to build pipeline infrastructure to minimize the need for trucking water The water is run through a Dissolved Air Flotation unit for treatment before being placed into secure water storage ponds

54 QUESTIONS? Acknowledgements: Brian Woodard, Devon