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Open Borehole Well-Test Methods for CO2 Storage Site Characterization Advanced Techniques for Site Characterisation: ENOS WP6 Workshop

23 April 2018

Mark Kelley (Battelle)

In conjunction with: C02GeoNet Open Forum 201824-25 April 2018San Servolo Island, Venice, Italy

Outline

Borehole Test Objectives

•Hydraulic Test Methods

•Composite Borehole (Reconnaissance)

•Discrete Interval Hydraulic Tests for low k and high k rocks

•Discrete Interval Geomechanic Tests - Mini-frac (HF), HTPF

•Equipment Considerations

Selected Open Borehole Tests

•AEP Mountaineer BA-02 Test Borehole (West Virginia)

•FutureGen Well (Illinois)

•Ohio Geol. Survey CO2 Well

•MRCSP CO2-EOR (Michigan)

Examples

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Borehole Hydraulic and

GeomechanicalCharacterization

Objectives

• Identify candidate intervals for CO2 injection/storage

• Quantify hydraulic properties of composite borehole

• Quantify hydraulic and geomechanicalproperties of discrete intervals (reservoir, caprock) for use in dynamic modeling

• Static formation fluid pressure (hydraulic head)

• Transmissivity, Kh

• Storativity, Ssh

• Skin, sk

• Min and Max Horizontal stress, Shmin, SHmax

Composite borehole reconnaissance

Discrete Intervaltesting

Timing of Borehole Hydraulic-Geomechanical Testing

• Usually done after borehole is drilled to TD (“drill-then test”) – but can also be done during drilling (“drill-and-test”)

• Consecutive Drill-then-test Pros/Cons

• (+) Less costly – test after drilling rig is moved off hole, often with support of service (workover) rig

• (-) possibility of pressure perturbations due to drilling

• Drill-and-test Pros/Cons

• (+) potentially shorter test times and better quality of the characterization data

• (-) more costly - standby drilling rig and test equipment costs that are incurred when either activity is not taking place.

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Composite Borehole Hydraulic Reconnaissance Methods

• Identify hydraulically conductive (inflow/outflow) intervals

• Quantify volume of inflow/outflow – indicator of interval kh

• Quantify hydraulic properties (kh) of composite borehole

Uses

• Mechanical flow meter (spinner) survey

• Hydrophysical (Fluid EC/temp) Logging

Example Methods

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Open Borehole (mechanical) Flowmeter Survey

• While pumping, flowmeter (run on wireline) is lowered/raised across the open borehole sections

• Tool string includes flowmeter, pressure, temperature probes and caliper

• Constant logging speed while logging

• Constant injection/withdrawal rate

• Repeat test for different injection/withdrawal rates

• Run baseline log before injection/withdrawal

• Record pressure recovery after injection/withdrawal

• Log temperature profile after pressure recovers

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Open Borehole (mechanical) Flowmeter Survey (cont’d)

• Provides vertical profile of volumetric inflow/outflow from the borehole

• Pressure recovery data can be analyzed for kh of composite borehole

• Relative kh of Individual flow intervals can be determined from observed change in logging speed across interval

• Repeat temperature log(s) provide qualitative information about location of hydraulically conductive intervals to corroborate flowmeter results.

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Example Open Borehole Flowmeter Survey AEP Mountaineer BA-02 Test WellWest Virginia

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• Purpose – BA-02 was drilled to provide geologic characterization data to support the design of a commercial-scale CO2 capture and storage facility (1.5 million metric tons of CO2

per year).

• Hydraulic well testing program was conducted to evaluate the injectivity potential of geologic formations in the ~2,200 ft (670 meters) open borehole section from 6,690 to 8,875 ft (2040 to 2705 m).

Source: Spane and Kelley. 2011: Mountaineer CCS II Project: Hydrologic Well Testing Conducted in the BA-02 Well American Electric Power Company Mountaineer Plant New Haven, West Virginia

Example Open Borehole Flowmeter Survey (cont’d)AEP Mountaineer BA-02 Test WellFlowmeter Data for 2, 4 and 6 BPM Surveys and Temp Logs

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6400

6900

7400

7900

8400

8900

0 2 4 6

De

pth

(ft

bk

)

Downward Flow Rate Past Depth (BPM)

BA-02 2, 4 and 6 BPM FlowMeter Surveys (Up Direction) ResultsApril 5-6 2011

6 BPM

4 BPM

2 BPM

Beekmantown C

Beekmantown B

Beekmantown A

Copper Ridge

Copper Ridge B Zone

Copper Ridge

Rose Run

Nolichucky

Wells Creek

Bottom of Casing

St. Peter

Black River

Gull RiverLower Chazy

6400

6900

7400

7900

8400

8900

113 118 123 128 133 138 143 148

De

pth

(B

K)

Temp (F)

BA-02 Well Final Temp SurveyApril 7, 2011

pre injection temp

17 hrs after injection temp

Beekmantown C

Beekmantown B

Beekmantown A

Copper Ridge

Copper Ridge B Zone

Copper Ridge

Rose Run

Nolichucky

Wells CreekSt. Peter

Bottom of Casing

Lower ChazyGull River

Black River

Hydraulic Reconnaissance Survey of Cambrian-

Ordovician Strata in Coshocton and Tuscarawas

Counties Ohio

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35 miles (56 km)

Typical brine injection interval with open borehole completion

Transect showing location of 5 brine injection wells

Flowmeter survey

conducted in 6 wells

Three hydraulically conductive Intervals could be correlated across the region.

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35 miles (56 km)

Flow zone 1

Flow zone 2

Flow zone 3

Different test types used for hydraulic testing depending on transmissivity

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Source: Solexperts (Ursula Rӧsli)

Discrete Interval (Packer) Hydraulic Tests

Test Equipment for Packer Tests

• an inflatable or mechanical, multiple-packer (straddle-packer) system for isolating test intervals

• pressure sensor system for monitoring real-time pressures within, below and above the test interval (and back-up downhole memory gauges)

• a data acquisition system (DAS) to record and display downhole test response (pressures) on a “real-time” basis (e.g., wireline or telemetry)

• a pneumatic or mechanically-activated downhole shut-in valve (to provide test system isolation at test formation depth) to facilitate/shorten test duration

• a tubing string for conveying the downhole packer test system to the test interval

• Crane, service rig, or similar means for deployment and retrieval of tubing string and other test equipment

• submersible pump, swabbing equipment, or other means (e.g., air lift system) for withdrawing fluid from tubing and/or test interval

• Surface pump, flowmeters, pressure sensors piping and valving for injecting and controlling, measuring water iinto tubing string/test interval (mini-frac test; injection fall-off test)

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Examples of Test Equipment

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Water tanks

Swabbing Tool

Straddle Packer

Service Rig andTubing String

Misc connections

PressurizedInjection fitting

Generator

Pressure SensorsReal-Time Analysis

Packer Tool/Shut-in Valve

Injection Truck

High pressure injection pump trailer

Examples of Test Equipment (cont’d)

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Straddle Packer

Service Rig andTubing String

wireline deployable straddle packer test tool

• Drawdown- build-up tests• Vertical interference tests• Mini-frac tests• Water sampling• Fixed packer spacing• Pump-rate limitations

Injection TruckBaker RCX Tool

Test equipment (cont’d) – considerations for testing low permeability rock

• hydraulic testing of low permeability caprock intervals requires special equipment/modifications.

• low permeability formations can be affected by borehole pressure history, temperature changes of fluid in the borehole, volume changes caused by deformation of test equipment, and the presence of gas in the formation and test system.

• Test systems with minimal packer compliancy (i.e., elasticity) and shut-in tool displacement stresses (i.e., zero displacement shut-in tool) should be used

• e.g., To minimize variation in packer pressure during pulse tests in low-permeability formations that can mask the actual formation response, HydroResolutions LLC designed a test tool with pressure accumulators hydraulically connected to the packers and shut-in valves.

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Example Straddle Packer Test Tool (configured for pulse testing)

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Source: Technical Report: Analysis of Straddle-Packer Tests in DGR Boreholes Revision 0 Doc ID: TR-08-32 (Geofirma Engineering)

- two inflatable packers, - a downhole shut-in valve, - a piston-pulse tool, - a slotted section, - a sediment trap, - sensor carriers, and - miscellaneous subs and

feedthroughs to connect the various pieces

The length of the test zone (packer spacing) can be varied

HydroResolutions Pulse-Test Tool

Test #1 – Slug Test and

Drill Stem Tests (DST)

• Induce instantaneous pressure increase/decrease in the test zone followed by recovery back toward static pressure conditions. The rate of pressure decay is used to infer the hydraulic properties of the test interval.

• Most commonly implemented by removing (e.g., swabbing) [slug withdrawal] test] or adding water to [slug injection test] the test tubing-string with shut-in valve closed, and then opening the valve.

• Slug test: the shut-in valve remains open during a slug test and fluid flowing into or out of the formation results in changing water levels within the tubing.

• DST test: (if recovery is slow), shut-in valve is closed after ~50% recovery; reduces wellbore accelerates recovery

• Radius of investigation = near wellbore

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Slug injection test

Straddle packer

with shut-in valve

Bottom of cased

borehole

Tubing string

Slug-DST Tests – Analysis

• Analysis of the slug test recovery response provides an estimate of the test-interval transmissivity (kh), average hydraulic conductivity (K) and storativity (S)

• Butler (1997)

• Peres et al. (1989)

• Analysis of DST recovery data provide estimates of T, K, S, sK, and (if pre-test trend conditions accounted for) static formation pressure conditions.

• Earlougher (1977) – for DST recovery analysis.

• Correa and Ramey (1987)

• Karasaki (1990)

• Radius of investigation = near wellbore

• can be greatly expanded by utilizing an observation well to monitor the surrounding pressure interference

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Test system forces > formation

Formation forces > test system

Transitional

Slug/DST Tests – Analysis

• Provides transmissivity (kh), average hydraulic conductivity (K) and storativity (S)

• Test has low sensitivity for S

• The slug-test responses are commonly analyzed with type-curve and deconvolution procedures discussed in Butler (1997) and Peres et al. (1989), respectively.

• Analysis of DST recovery data provide estimates of T, K, S, sK, and (if pre-test trend conditions accounted for) static formation pressure conditions.

• DST recovery analysis by standard straight-line semi-log procedures in Earlougher (1977)

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Example Type-Curve Analysis of Slug Test (FutureGen Site, Illinois)

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Slug Test Analysis

0.0

0.2

0.4

0.6

0.8

1.0

0 1 10 100 1000

Dim

ensi

onle

ss H

ead

and

Hea

d D

eriv

ativ

eTime, minutes

Data

Data Derivative

Type Curve

Derivative Plot

FutureGen Pilot Well

Slug Test Analysis

Test: Zone 2/SW-1Test Interval: Lower Mt. Simon

Inner Zone Analysis

Parameters

T = 4.15 ft2/dayK = 0.055 ft/dayk = 14.1 mDkb = 1060 mD-ft

Se2sK= 4.1E-3

rsk = 4.1 ft

Test Propertiesrc = 0.1247 ftrw = 0.4577 ft b = 75.0 ft

ρfw = 1.032 g/cm3

μfw = 0.724 cpΔP = 92.59 psi Outer Zone Analysis

ParametersT = 3.00 ft2/dayK = 0.040 ft/day

k = 10.2 mDkb = 770 mD-ft

Source: Kelley et al., 2012; Borehole Completion and Characterization Summary Report for the Stratigraphic Well, Morgan County, Illinois; PNWD-4343; U.S. Department of Energy Award Numbers DE-FC26-06NT42073 and DE-FE0000587

1780

1790

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1810

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1840

1850

1860

02/2

1 0

7:2

6

02/2

1 0

8:2

6

02/2

1 0

9:2

6

Lower Mt. Simon Slug-DST #2

(SLUG TEST ONLY -NO DST)Feb 21; Real-time P

3.5 inch tubing

open SIT @07:50: closed SIT@08:50

Raw Data

Test interval length = 75 ft (23 meters)depth to test interval ~4200 ft (1320 m)

shut-in valve remains open

T=41.5 ft2/d (4.5 E-05 m2/s)

Example Type-Curve and Straight-Line Analysis of DST (FutureGen Site, Illinois)

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1700

1705

1710

1715

1720

1725

1730

1 10 100

Do

wn

ho

le P

ress

ure

, p

sia

Horner Time, (t + t')/t'

De-Trended Recovery

Analysis Regression Line

FutureGen Pilot WellDST Recovery Horner Semi-Log Analysis

Test: Zone 3A/DST-1Test Interval: Upper Mt. Simon

Analysis ParametersT = 37.2 ft2/dayK = 0.20 ft/dayk = 52.0 mD

kb = 9,620 mD-ft

S = 4.3E-4CD = 0.46

CDe2sK= 7.2sK = +1.38

Test Properties

rc = 0.258 ft

rw = 0.467 ftreqv = 9.3E-3 ft

b = 185 ftρw = 1.032 g/cm3

Qc* = 0.603 bpm

Δs = -10.70 psi/log cycle

0.1

1.0

10.0

100.0

1000.0

0.1 1.0 10.0 100.0

Rec

ove

ry a

nd

Rec

ove

ry D

eriv

ativ

e, Δ

P,

psi

Agarwal Equivalent Time, min

De-Trended Recovery

Detrended Recovery Derivative

Type Curve

Derivative Plot

FutureGen Pilot WellDST Recovery Type-Curve Analysis

Test: Zone 3A/DST 1Test Interval: Upper Mt. Simon

Analysis ParametersT = 37.2 ft2/dayK = 0.20 ft/dayk = 52.0 mD

kb = 9,620 mD-ftS = 4.3E-4

CD = 0.46

CDe2sK= 7.3

sK = +1.38

Test Properties

rc = 0.258 ft

rw = 0.467 ftreqv = 9.3E-3 ft

b = 185 ftρw = 1.032 g/cm3

Qc* = 0.512 bpmtcp* = 22.71 min

Type-Curve Analysis Upper Mount Simon

Straight-Line (Horner) Analysis Upper Mount Simon

1620

1630

1640

1650

1660

1670

1680

1690

1700

1710

1720

02/2

3 0

8:3

8

02/2

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8:5

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9:2

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9:3

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9:5

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0:0

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3 1

0:1

9

02/2

3 1

0:3

3

02/2

3 1

0:4

8

Upper Mt. Simon Slug-DST#1

Feb. 23; Real-time data

open SIT@8:54; closed SIT@9:14

Raw Data

Close shut-in valve

Test interval length = 185 ft (56 meters)depth to test interval ~4200 ft (1320 m)

Source: Kelley et al., 2012; Borehole Completion and Characterization Summary Report for the Stratigraphic Well, Morgan County, Illinois; PNWD-4343; U.S. Department of Energy Award Numbers DE-FC26-06NT42073 and DE-FE0000587

T=37.2 ft2/d (4.0e-05 m2/s)

Test #2 – Pulse Test

• Applicable to low permeability rocks (i.e., 10-9 m/s)

• Similar to slug test except that the test zone is shut-in (by closing the shut-in valve) during entire recovery period.

• Withdrawal (PW) or Injection (PI) mode

• volumes of fluid are smaller during pulse tests (i.e., per unit pressure change) in comparison to slug tests, therefore, the radius-of-investigation is accordingly smaller.

• pulse tests more susceptible to near well formation heterogeneities and skin effects

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Pulse Test Analysis

• same analytical equations used for analysis of slug tests (e.g., Cooper et al., 1967)

• The equations, however, must be modified to account for the closed-system wellbore storage test conditions

• Kh, k, S

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0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

10 100 1000 10000 100000 1000000 10000000

Time, min

Dim

ensio

nle

ss H

ead,

H

Test Properties

Kh = 3.3E-11 ft/s

S = 1E-5

KD = 10.0

rw = 0.333 ft

b = 65 ft

Predicted Caprock

Test Comparison

Slug Test

Pulse Test

Comparison for Pulse (closed) and Slug Test (open) Responses (adapted from Reidel et al., 2002)

Recovery time

17 hours 19 years

Test #3 - Constant-Rate Pumping Test

• Water is withdrawn from (or injected into) a borehole at a uniform rate for an extended period of time (e.g., 8 hours to 48 hours).

• Pressure is monitored during the active pumping phase and the recovery phase following pumping.

• Radius of investigation potentially very large if pumping period is extended

• Observation wells, if available, can be monitored to extend radius of investigation

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Submersible pump

200

250

300

350

400

450

500

550

600

650

700

02

/07

12

:00

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/07

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:00

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/07

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/08

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/08

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/08

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/09

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/09

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:00

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/09

12

:00

Pre

ssu

re A

bo

ve P

um

p I

nta

ke (

psi

a)

Pump Intake Pressure (psia)

Pumped from 12:52 to 17:17 (4.4 hrs) on 2-7-12; recovered overnight. Estimated volume pumped 34,680 gals; average pumping rate = 131 gpm.

Pumped from 8:06 to 16:45 ( 8.65 hrs) on 2-8-12;

recovered overnight. Estimated volume pumped 57,600 = gals; average pumping rate = 110 gpm.

Example constant rate pumping test

Constant-rate Pumping Test – Analysis

• Standard analytical methods include type-curve matching (observation wells) and straight-line methods (pumped well)

• Type-curve-matching methods include: Theis(1935), Hantush (1964), and Neuman (1975)

• Straight-line methods: Cooper and Jacob (1946)(for buildup analysis) or Horner (1951) (for recovery analysis).

• provides kh, skin, radius of investigation, presence of boundaries

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Example Constant-Rate Pumping TestAEP Mountaineer, West Va.Test Interval 8,320 to 8,875 ft (2536 to 2706 meters)

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3600

3800

4000

4200

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4600

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/02

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/02

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/02

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/04

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:00

Pre

ssu

re (p

si)

constant rate injection test

withdrawal slugtest #2

1 -minute Injection Slug test

withdrawal slugtest #1

Packer inflation followed by initial injection slug test

(not analyzable)

releasepacker

@17:30Tested SIV

BA-02Lower CopperRidge (>8320 ft)

5-2-11 to 5-4-11

Raw Data

8-hour injection

6400

6900

7400

7900

8400

8900

0 2 4 6

De

pth

(ft

bk

)

Downward Flow Rate Past Depth (BPM)

BA-02 2, 4 and 6 BPM FlowMeter Surveys (Up Direction) ResultsApril 5-6 2011

6 BPM

4 BPM

2 BPM

Beekmantown C

Beekmantown B

Beekmantown A

Copper Ridge

Copper Ridge B Zone

Copper Ridge

Rose Run

Nolichucky

Wells Creek

Bottom of Casing

St. Peter

Black River

Gull RiverLower Chazy

Test Interval

Example Constant-Rate Pumping TestAEP Mountaineer, West Va.Test Interval 8320 to 8875 ft (2536 to 2706 meters)

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Type Curve and Derivative Plot Analysis of the Recovery Phase

250

300

350

400

450

500

550

1 10

Do

wn

ho

le P

ress

ure

Re

cove

ry,

ΔP

, p

si

Agarwal Equivalent Time, minutes

Recovery Data

Linear Regression

AEP-BA-02Lower Copper Ridge/Zone 2Depth: 8,320 - 8,875 ftInjection Recovery Fall-Off Test

Inner Zone: Semi-Log Straight-Line Analysis

ΔP = 277.2 psi/log

Inner-Zone Analysis ParametersT = 5.78 ft2/dayK = 0.19 ft/dayk = 71.6 mDS = 8.9E-5 (calculated)

Se2sk = 7.56e-03sK = -2.2 ρfw = 1.19 g/cm3

μfw = 1.212 cprc = 0.102 ftrw = 0.354 ftb = 30.0 ftQavg = 2.1 bpm

Straight-Line Analysis of the Recovery Phase

T inner zone =5.78 ft2/d (6.2 E-06 m2/s) T outer zone = 254 ft2/d (2.7 E-04 m2/s)

Test #4 – Constant-Pressure Injection (Fall-Off) Test

• Applicable to low permeability rocks (i.e., 10-9 m/s)

• Maintain constant pressure; record flow rate

• At the end of injection, shut-in and record pressure recovery (pressure fall-off)

• radius-of-investigation is greater than pulse tests, but still localized

• E.G., 8 ft for tests of 5 hours or less, conducted within dense caprock with hydraulic conductivity of 10-

11 m/s.

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Source: DEEP BOREHOLE FIELD TEST:

DESIGN REPORT

Forward simulation

Author: Ursula Rösli

Report V2A-2469, 1 April 2016

Solexperts AG

CH-8617 Mönchaltorf (Switzerland)

Example Constant-Pressure Injection TestOhio Geol. Survey CO2 #1 WellTuscarawas County, OhioTest Interval Rose Run Formation7,377 to 7,396 ft (2248 to 2255 meters)

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Raw Data

Type-Curve Analysis

Straight-Line Analysis

T=0.019 ft2/d (2.2 E-07 m2/s)

Test-History Match

• When a series of tests are conducted in a sequence, the entire test sequence can be simulated

• Decreases uncertainty compared to individual tests

• Software (models) for simulating test sequences• KGS model (Liu and Butler 1995) for slug testing

• WTAQ model (Moench 1997) for constant-rate injection/pumping tests

• nSIGHTS Software (all types of tests)

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Hydraulic Test sequencing – low perm rocks

• PSR phase – pressure recover towards static conditions.

• Pulse withdrawal test –gives a rough approximation of the borehole near formation properties.

• HI test and the related pressure recovery –provide more quantitative information on the formation properties (with/without skin) and heterogeneities, and possible presence of hydrologic boundaries. 33

Source:DEEP BOREHOLE FIELD TEST:DESIGN REPORTForward simulationAuthor: Ursula RösliS o l e x p e r t s A G03 May 2016

PSR (pressure shut-in recovery) ->Pulse (withdrawal) ->HI (constant head injection)->HIS (recovery)

Hydraulic Test sequencing – low perm rocks

Examples:

• Shut In -> PW->PI

• Shut In -> DST->PI

• Shut In -> PW1 ->PW2->PW3

34

source: Analysis of Straddle-Packer Tests in DGR Boreholes Document ID: TR-08-32 Authors: Randall Roberts and David Chace, HydroResolutions LLC, Richard Beauheim, and John Avis, Geofirma Engineering Ltd. ; Revision: 0; Date: April 12, 2011

Hydraulic Test sequencing – higher perm rocks

• PSR phase - pressure recover to static conditions after system installation and packer inflation phase.

• The slug withdrawal test (SW) -rough approximation of the formation properties and the feasibility of a pumping test.

• The shut-in phase after the slug test (SWS) – helps to achieve static formation pressure in rather short time before the start of the following test sequence.

• Pumping test (RW) - and the related pressure recovery should provide more quantitative information on the formation properties (with skin) and heterogeneities, and possible presence of hydrologic boundaries.

35

Source:DEEP BOREHOLE FIELD TEST:DESIGN REPORTForward simulationAuthor: Ursula RösliS o l e x p e r t s A G03 May 2016

PSR (pressure shut-in recovery) ->Slug (withdrawal) ->recovery->RW (constant rate withdrawal) -> RWS (recovery)

Example Test History Match of a sequence of hydraulic tests using nSIGHTS SoftwareFutureGen Site

36Analysis by R. Roberts, HydroResolutions Data from FutureGen site: F.

Spane; M. Kelley

T=5.5 E-05 m2/s) from all tests

T from slug withdrawal test shown previously was 4.5 E-05 m2/s

Transmissivity Profile PlotBA-02 Test Well: AEP Mountaineer, West Va

37

• Summarizes results

of Packer Tests

conducted in a

borehole

• useful for illustrating

intervals most

suitable for CO2 injection

Geomechanical (Stress)Tests

• Hydraulic Fracture (HF) tests (aka mini-frac)

• these tests create new fractures

• HF tests provide estimates for σH direction and for σhmagnitude

• Hydraulic Tests on Preexisting Fractures (HTPF)(Cornet, 1993; Haimson and Cornet, 2003).

• measure the pressure required to reopen preexisting fractures (i.e. the normal stress acting on the fracture)

• provide a means for determining the magnitude of σH, which cannot be precisely constrained using HF tests alone..

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Example Geomechanical(Stress)Tests(FutureGen Site, Illinois)

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FMI Log Image of Fracture Created in HF Test Zone GM-13; Fracture is Vertical and Oriented NE-SW.

4130 ft kb (4116 ft bgs)

4140 ft kb (4126 ft bgs)

❑ maximum horizontal principal stress, H, is oriented N 51±4°E

❑ magnitude of h in the Mount Simon from 2 HF tests:

❑ h = 3,240 ± 330 psi at 4,156 ft ❑ h = 2,800 ± 100 psi at 4,236 ft

❑ Maintaining injection pressures lower than 2,800 psi at a depth of 4,236 ft should avoid hydraulic fracturing within either the Mount Simon reservoir or the overlying Eau Claire shale caprock.

❑ The magnitude of H is the largest principal stress (i.e., h<v<H); this implies a regional strike-slip tectonic stress regime.

Source: Cornet, F.H., 2014. Results from the In Situ Stress Characterization Program, Phase 1: Hydraulic Tests Conducted in the FutureGen Stratigraphic Pilot Well. February 2014.

Summary/Review• Flowmeter logging is one type of open borehole reconnaissance method for

identifying hydraulically conductive intervals that may be candidates for CO2 storage.

• Examples were presented from AEP Mountaineer (West Virginia) and Central Ohio, both Cambrian-Ordovician strata

• Five types of discrete interval (packer) hydraulic tests were discussed, including, slug tests, DST tests, pulse tests, constant rate tests, and constant pressure tests

• Examples were presented from FutureGen (Illinois), AEP Mountaineer (West Virginia), Ohio Geological Survey CO2 Well #1 (Central Ohio)

• Two types of discrete interval (packer) geomechanical (stress) tests were discussed, including, HF and HTPF tests

• Example presented from FutureGen (Illinois)

• Equipment requirements for conducting discrete interval hydraulic and geomechanical tests were discussed.

• Wireline deployable test tools can be attractive option in some cases

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Information included in this presentation came from several Battelle projects plus information provided by the following individuals and organizations: - Frank Spane (Pacific Northwest National Laboratory, Richland Washington)- Ursula Rӧsli (Solexperts AG of Mönchaltorf-Zurich, Switzerland-- Randall Roberts (HydroResolutions, LLC, Carlsbad, New Mexico)

Acknowledgments