Water Issues and Challe

Associated with Shale Gas Pr

John Veil

410

‐212

‐0950

john@veilenvironmental.com

www.veilenvironmental.com

2011 International Water Conferen

Orlando, FL

November 13

‐17, 2011
Topics for Discussion Intro to produced water

 Water needs and production for different

types of hydrocarbon

 Steps in shale gas production Well completion and hydraulic fracturing Wastewater management

 Cost considerations

 Water needs to produce shale gas

 Which chemical additives are used in frac

fluids and why?

 Frac Focus website
What is Produced Water?

 Water that comes to the surface with oil

and gas

 Contains many chemical constituents

– Salt content (salinity, total dissolved solids

[TDS], electrical conductivity)

– Oil and grease

• Composite of many hydrocarbons and other

organic materials

– Toxicity from various natural inorganic and

organic compounds or chemical additives

– NORM
Produced Water Volume

 Largest volume waste stream from oil and gas produ

– Worldwide estimate – 77 billion bbl/year (2003 SPE paper)

– U.S. – 21 billion bbl/year (Clark and Veil 2009)

• ~57 million bbl/day or 2.4 billion gallons/day

• Metric: 333 million m3/year or 913,000 m3/day

 Ratio of water‐to‐oil

– World‐wide estimate – 2:1 to 3:1– U.S. estimate – 5:1 to 8:1

• with more complete data sets that include TX and OK data, this woul

Clark and Veil 2009 can be downloaded a

http://www.veilenvironmental.com/produced_w
Produced Water Volume Changes Over Time in a Field

OIL AND GAS

CBM GAS

WATER

Producing TimeProducing Time

Rate Rate

WATER

• Conventional oil and well• Coal bed methane we• Shale gas wells behavsimilar manner
Overview of Water Needs an

Production by Hydrocarbon 
Conventional Oil and Gas

 Water needs

– Many wells receive hydraulic fracturing

– Water flood as field matures

 Produced water generation

– Starts low then steadily climbs– Continues for the life of the well

 Produced water management – most common practices

– Offshore – treat and discharge to ocean

– Onshore ‐ inject
Coal Bed Methane (Coal Seam Natural Gas)

 Water needs

– Many wells receive hydraulic fracturing

 Produced water generation

– Starts high then gradually declines

 Produced water management – most common practices

– Alabama, Powder River Basin – treat and discharge to river

– Other U.S. ‐ inject
Shale Gas

 Water needs

– All wells receive hydraulic fracturing

 Produced water generation

– Initial volume of flowback water (primarily consists of the frac fluid

used for fracking)

• Concentrations of TDS and other constituents increase over time; ofte

high

– Long term produced water flow (blend of formation water found in 

pores and residual frac fluids)

• Continues for many months

– Not all of frac fluids return to surface

• Marcellus – 10‐15%• Other plays – higher

 Produced water management

– variable options; depend on local conditions

– Injection is most common
Heavy Liquid Crude Oil

 Water needs

– Steam flood to help move heavy oil to production wells

 Produced water generation

– Much of the water results from the injected steam used in steam 
Oil Sands

 Water needs

– Steam (or water) injection used in large volumes

 Produced water generation

– In‐situ production methods

• some water is formation water, but much is from the injected steam

– Oil sand mining production methods and subsequent processing s

generate wastewater
Shale Gas, Hydraul

Fracturing, and 

Water Managemen
Importance of Shale Gas to the USA

 Natural gas is an important energy source for the United States

formations represent

a growing source of natural gas for the na

are among the busiest oil and gas plays in the country.

Source: DOE/EIA Annual Energy Outlook 2011
U.S. Shale Plays

 The most active U.S.

shale plays to dateare:

– Barnett Shale in Texas,– Fayetteville Shale in

Arkansas

– Haynesville Shale in

Louisiana

– Marcellus Shale in

Pennsylvania, New York,

and West Virginia

– Woodford Shale in

Oklahoma

– Eagle Ford Shale in Texas

– Bakken Shale in North

Dakota

– Utica Shale (beneath

Marcellus)

Source: DOE/EIA website
New Report on Global Shale Gas Reserves

 U.S. Department of Energy released

a new report on April 5, 201

assessed 48 shale gas basins in 32 countries, containing almost 7

formations around the world.

http://www.eia.gov/analysis/studies/worldsha
Steps in the Shale 

Gas Process

Gaining Access to the Gas (Le

Searching for Natural GasPreparing a SiteDrilling the WellPreparing a Well for Producti

(Hydraulic Fracturing)Gas Production and Water

ManagementMoving Natural Gas to Mark

Well Closure and Reclamatio

 Steps involving water are

shaded

Source: Fayetteville Shale

Information website

http://lingo.cast.uark.edu/LINGOPUBLIC/index.htm
Water Issues in Site Preparation

 Need to consider stormwater runoff from

all land areas disturbed during

construction

– Follow proper sediment control practices

– Stabilize exposed surfaces
Water Issues in Drilling

 Water is needed to make up drilling

fluids

– In the Marcellus Shale the volume of

water used for drilling volume is

about 80,000 gallons per well.

 Drilling waste is sent to lined pits or

into

a closed

‐loop system employing

tanks
Well Completion and Hydraulic Fracturing (HF)

 What is HF?

 Why is HF used?

 The well completion process
What Is HF?

 “Hydraulic” ‐ Involves high‐rate, high pressure injection of wate

proppant material such as sand, and various chemicals

 “Fracturing” ‐ Process used to create cracks in the shale rock th

natural gas to move to the well where it can be collected

 Different terms

– Frac/frack– Frac /frack job

– Fraccing/fracking/fracing

Source: C.B. Veil – taken in Ithac
Why Is HF Used?

 Shale rock is very dense and does not contain natural pores

– HF creates a network of small cracks in the rock that extend out a

feet laterally and vertically away from the well

 Virtually no shale gas wells in the U.S. would be developed unle

 It is controversial and expensive, but is a critical element in cos

production

Source: K. Fisher, Pinnacle
Well Completion Process

 Most shale gas wells

are drilled ashorizontal wells with

up to 1 mile of lateralextent through the

shale formation

 In order to get gas

from the formationinto the wellbore,

companies mustfollow two steps:

– Perforation– HF

Good animation of completion process:http://marcellus.psu.edu/resources/drilling/in

Source: T. Murphy – Penn State Marcellus Center for Outreach 
Well Completion Process (2)

 On

a long horizontal leg, completion

in done in

a series of stages, each of

which is

a few hundred feet long

– Perfs are made using small explosive

charges that are lowered to the

desired depth on

a cable

– HF is done for several hours for each

stage

– Pressure is held on the well and

a

plug is set to isolate that fracturedinterval and allow stimulation of the

next stage

– The next stage is perfed and fracked

Source: Frac Foc

Source: J. Veil
Water Needed for Frac Jobs

 Most wells require up to

5 million gallons, but

the trend is to have more stages and use more

water

– Individual volume is not critical, but collectively

can be important within

a region

 Source of water:

– Stream, river, or lake

– Well– Impoundment created by producer

– Public water supply

 Piped to site vs. delivery in tank trucks
Frac Job Pumps Large Volume of Water, Sand, a

Additives into the Well in Stages
Management of Frac Flowback Water (1)

 Large volume of flowback returns to the surface in first few hou

– Typically collect in pits/ponds
Management of Frac Flowback Water (2)

 Some larger sites collect

flowback in brine tanks

 Filtered and reused in

frac fluid for future well

 Over time, smaller volume

of produced water flows

to surface

– Collected in onsite tanks
Management of Frac 

Flowback Water (3)

 Collected water must be removed from

site

 Typically is collected by tank trucks and

hauled offsite to:

– Commercial disposal wells– Wastewater treatment plants

• Need to treat water to very low TDS or

return clean brine to producers

– Filtration and reuse facilities (orange tanks

on previous slide)

 Most Marcellus producers reuse the

flowback water after filtration.

– The water is blended with fresh water to

make up new frac fluids.
Category Cost Component (Some or all may be applicable)

Prior toOperations

Prepare feasibility study to select option (in‐house costs and outside cObtain financingObtain necessary permits

Prepare site (grading; construction of facilities for treatment and stora

installation)Purchase and install equipmentEnsure utilities are available

DuringOperations

UtilitiesChemicals and other consumable supplies

Transportation

Debt serviceMaintenanceDisposal feesManagement of residuals removed or generated during treatmentMonitoring and reporting

Down time due to component failure or repairClean up of spills

AfterOperations

Removal of facilities

Long‐term liability

Site remediation and restoration

Components Contributing to Total Cost of Wastewater M
Difficulty in Accurately Assessing and Compa

 Cost data from vendors

– May not include all cost components shown on previous slide

– Comparative costs between vendors rarely include the same list o

components

 Cost data from users

– Companies should have accurate cost data, but they rarely will sha

detailed costs

– This is considered proprietary information related to competitiven

 Relatively few published papers or reports give comprehensive 
How Does a Company Choose a Wastewater Management Option?

 Many alternatives are available for managing

produced water

 Companies must consider:

– Volume of water generated

– Chemical and physical characteristics

– Practicality and feasibility of an option

– Regulatory requirements that allow or block an

option

– Long‐term liability of chosen options

– Costs of using an option in

a way that meets

regulatory requirements

• Need to consider full cost load
Water Use Data in Susquehanna 

• Total water use: 1.6 billion gallons

on 553 wells (6/08 to 3/11)

• Average total volume of fluid used per well:

4.2 million gallons per well

― 3.8 million gallons of fresh water (90%)

— 0.4 million gallons of reused flowback (10%)

• 30

‐day avg. recovery of flowback: 8%

• Total amount of flowback: 117 million

gallons (6/08 to 3/11)

— Reuse 75 million gallons

— Disposal 42 million gallons

— 64% flowback reuse
Statistics on Water Requirements for Marcellus 

 Make estimate of maximum volume of water neede

Marcellus Shale fraccing needs

– Estimate volume of water per well

– Estimate maximum number of wells in

a year
Pennsylvania Drilling Permits and Wells Drilled

Year Marcellus Shale

Drilling PermitsIssued

Marcellus ShaleWells Drilled

2007 99 18 (July

–

December)

2008 519 1962009 1,985 763

2010 3,446 1,454

 Assuming

a hypothetical maximum is double the 2010 total

=

2,908 wells
West Virginia Drilling Permits and Wells Drilled

Year Marcellus Shale Drilling

Permits Issued

Marcellus Sha

Drilled

2007 152 1432008 400 2742009 424 472010 244

2

Source: WV DEP website

 Assuming

a hypothetical maximum is double the 2008 total

=

548 wells
New York Drilling Permits and Wells Drilled

 New York has moratorium on Marcellus Shale wells

 No good way to predict maximum number of wells

 Chose to estimate maximum New York wells to be the same as 

West Virginia wells

= 548 wells

Year Total Drilling Permits Issued (not

necessarily Marcellus Shale)

Total WellsDrilled

2008 744 ??2009 552 ??2010 302 (January – August) ??

Source: presentation made by Jack Dahl, NY DEC, August 24, 2010
Hypothetical Maximum Water Demand for Marce

State Hypothetical Maximum Number of

Wells Drilled in

a Year

Annual Volume assuming

of water needed per well

PA 2,908 14.5 

WV 548 2.7 

NY 548 2.7 

Total 4,004 20 billion gals/yr

 Caveats

– estimates of maximum wells drilled could significantly overestimate 

underestimate the actual quantity

– assumed maximum number in one state will not necessarily corres

maximum in each of the other states

– As gas companies refine and improve their efforts to recycle and re

and produced water from wells already fracked, the water needed 

decrease

– if operators drill longer horizontal wells with more frac stages, the v

could increase
Actual Water Withdrawals for 2005 (in MGD)

Category New York Pennsylvania West Virginia 

Public Supply 2,530 1,420 189 

Domestic 140 152 34 

Irrigation 51 24 <1 

Livestock 30 62 5 

Aquaculture 63 524 53 Industrial 301 770 966 

Mining 33 96 14 

Thermoelectric 7,140 6,430 3,550 

Total

10,288 9,478 4,811 

Source: USGS report (Kenny et al. 2009)
Comparison of Marcellus Shale Water Needs wit

Withdrawal

Volume Percentage Wa

Required for Sh

Production ComTotal Withdraw

Water needed for shale gas 55 MGD

‐

Total water withdrawal 24,577 MGD 0.22%
Arkansas Completions in the Fayetteville Shale

Year Fayetteville Shale Completion

2007 4112008 6832009 8392010 862

 Assuming

a hypothetical maximum is double the 201

1,724 wells
Actual Water Withdrawals for 2005 (in MGD)

Category ArkansasPublic Supply 266Domestic

0

Irrigation 1,510Livestock 23.3Aquaculture 10.6Industrial 113Mining

1

Thermoelectric 2,000Total

3,920

Source: USGS report (Kenny et al. 2009)
Comparison of Fayetteville Shale Water Needs w

Actual Withdrawal

Volume Percentage Wa

Required for Sh

Production ComTotal Withdraw

Water needed for shale gas

(assume

5 MG/well)

23.6 MGD

‐

Total water withdrawal 3,920 MGD 0.6%
Frac Fluid Chemicals

 What are the ingredients?

 Why are those chemicals used?
Frac Fluid Composition

 Water makes up ~90% of volume

 Sand makes up ~10% of volume

 All other chemical additives make up ~0.5% of volume

Source: Shale Gas Primer, GWPC and ALL
Why Chemical Additives Are Used

Source: Shale Gas Primer, GWPC and ALL
Why Chemical Additives Are Used (2)

Source: Shale Gas Primer, GWPC and ALL
Chemical Disclosure Rules Adopted by States

 One of the most contentious topics surrounding hydr

fracturing is that companies have not shared detailed

information with regulators or the public on which ch

actually used in frac jobs.

 National legislation requiring chemical disclosure was 

into Congress several years ago but was not passed.

 Several states have since passed their own chemical d

requirements

– Wyoming– Arkansas– Pennsylvania– Texas– Montana– Michigan–

6 other states have proposed regulations
Chemical Disclosure Registry

 In April 2011, the Ground Water Protection Council an

Interstate Oil and Gas Compact Commission opened

a 

system to host information about the chemical additiv

frac fluids and their ingredients

– Data entry is voluntary and is done by the gas companie

 Any interested person can visit the website and search 

on

a specific well

 As of November 10, data had been entered on nearly 

www.fracfocus.org
Frac Focus Homepage
Example of Registry Record for Well in Texa

Chesapeake Well, Bing 2H, Tarrant County, Texas (Frac Date 3/21/11)
Conclusions

 Shale gas is an important contributor to the U.S. oil and gas mark

– Its importance and proportional contribution is growing yearly

 Nearly all shale gas is produced using horizontal wells that must 

 The HF process involves lots of water and sand plus various chem

that allow for more productive and safer operations

 In the Marcellus and Fayetteville shales, there appears to be suff

freshwater available to meet shale gas operational needs

– It is not available at all times or in all locations

– Operators must plan ahead and procure water when stream levels a

 The flowback and produced water from shale gas operations req

disposal or management

 Injection is almost always a preferred choice unless:

– Good injection formations are not available locally

– Fresh water is in short supply, thereby adding value to recycling flow– A company chooses to follow sustainable practices and voluntarily l

or reuse

 Reuse of treated flowback for new frac fluids is growing in popu