Environmental Impacts of Oil and Gas Exploration and Production: Ground Water Impacts at OSPER Sites,

Osage County, Oklahoma

*Yousif K. Kharaka, James J. Thordsen, Evangelos Kakouros, and Gil Ambats

U. S. Geological Survey, Menlo Park, California, USA

GSA Annual Meeting October, 2005

Financial support from DOE-NETLDrilling support from EPA-NRMRLOsage Nation Tribal AuthoritiesU.S. Army Corps of Engineers

Distribution of Petroleum wells in Oklahoma, Osage County, & the study Area

Topics Discussed 1-  OSPER “A” site, Osage County, OK.

2-  Chemical & isotopic compositions of source & ground waters at OSPER “A” site.

3- Delineating the plume boundaries at “A”.

4- Processes--Mixing (brine, prec. & GW), ET & water-rock-bacterial interactions.

5- Future plans & concluding remarks.

OSPER “A” Site• Oil production (100,000 bbl) from shallow.

Pennsylvanian sandstones started in 1912, mostly completed by 1937.

• No site activity for 65-70 years.

• No waterflooding at this site

• All the produced water (~1million bbl) released to ground surface; petroleum initially collected at oil pit.

• Deep erosion of northern part of the site

0

N

B

B

B B

B B

B

B BB

BB

B

B

BB

BB

B

B

B

B

B

B

B

B

BB

Legend

O il-im pacted soils

Sandstone outcropS ligh tly to deep ly eroded areas

Wann Form ation

O ld redw ood tanksDrainage trace

Terrace edge in deeply eroded areas

Artifica l fill, asphaltic o il and w eathered o il

C lem Creek sand m em berLow er sha le m em ber,

m inor sandstone

Pennsylvanian

Late P le istocene/H olocene

C olluvia l gravel

LayerA rea

BCobbles and boulders

Aeolian sand, silt, and clay,

B

P

P

P

P

?

PN atura l so il pedesta l w ithin deeply eroded area

Trees

Trees

Trees

Trees

Trees

Trees

Trees

G rass,fo rbs

R o a d

G rass,fo rbs

G rass,fo rbs iso la ted trees

G rass,fo rbs, iso la ted trees

x

x

x

xx

x

xx

x

x

x

x x

x x x

xx

xx

x

x

x

x

AE13

AE14

AE15

AE16

AE18

AE17

AA01

AE01

AE02

AE19AA03

AA02

AA04

AE04AE09 AE10

AE11

A E 12

AE06

AE07

AE05

AE08

AE03

AP-01

SkiatookLake

50 100 ft

0 30 m2010

0

TRANSECT(Fig. 9)

Geology Map

Upper area (south) • gentle slope• tree kills from early(?) salt

releases• revegetated with grasses

Asphaltic pits • highly weathered oil• one pit contains relatively fresh

tank sludge(?)

Lower area (north)•steeper slope•prominent salt scar (~2 m deep)•salt (& gypsum) at surface

Photo by Ken Jewell,

USEPA (Jan. 2004)

AA-02

Sampling Trips to the Sites

March 2001--- Source fluids from oil wells, GW, and Skiatook Reservoir. Surface pools at both sites.

February 2002 --- ~60 Geoprobe, auger and rotary wells drilled, cored, completed and sampled at and two sites.

June 2002 --- Water level, conductance, and T measurements, followed by collection of ~40 water and a few oil samples.

November 02 --- Drilling with geoprobe and sampling.March-April 03 ---Drilling (EPA auger) and sampling.January 2004 --- (9) deep wells (WRD air) at “A”, and

sampling.

May 2004 --- (4) deep (EPA auger) wells at “B”; sampling.

February 2005 --- Water levels and sampling at both sites.

September 2005 --- Weir discharges.

0 50 10050100

Na

Ca

Mg

HCO3

SO4

Cl

01OS-111 - Skiatook Lake nr ACE

224 µS/cm

03/10/01 pH = 6.71 TDS = 153 mg/l

0 50 10050100

Na

Ca

Mg

HCO3

SO4

Cl

01OS-106 - Lebow #8

184800 µS/cm

03/08/01 pH = 6.29 TDS = 162232 mg/l

0 50 10050100

Na

Ca

Mg

HCO3

SO4

Cl

02OS-426 - AA-02s

19800 µS/cm

06/12/02 pH = 6.23 TDS = 11659 mg/l

0 50 10050100

Na

Ca

Mg

HCO3

SO4

Cl

02OS-427 - AA-02d

3420 µS/cm

06/12/02 pH = 6.91 TDS = 2761 mg/l

0 50 10050100

Na

Ca

Mg

HCO3

SO4

Cl

02OS-431 - AE-13

19900 µS/cm

06/13/02 pH = 5.63 TDS = 12302 mg/l

0 50 10050100

Na

Ca

Mg

HCO3

SO4

Cl

02OS-438 - AR-01

526 µS/cm

cc

06/13/02 pH = 6.46 TDS = 435 mg/l

“A” site Stiff Diagrams

New wells (1/04)

Traversea-a’

Site A - a-a’ traverse (with tritium)[update 10/12/05]

Alt

itu

de, i

n m

eter

s ab

ove

sea

leve

la-a’ traverse

125 150 175 200 225

Distance along traverse, in meters

26,100

125 150 175 200 225

Distance along traverse, in meters

26,100

AE06AA10AE55

1820

2,000

AE06AA10AE55

1820

2,000

220

225

230

AE07

Southpits

50-100

200

205

210

215

0 25 50 75 100

low: 215.8 m (2/2003)

Skiatook Lake levelshigh: 219.1 m (3/2004)

1670

1950

10,800??

TDS (mg/L)

10,000

2,000

10,000

AA06AE51

AA01AA02

North

SkiatookLake

DRY

salt scar erosion

AE13AA61

AA04

16,10022,400

4720

9,700

19,100

29,900

11,3004810

20,000

15,000

15,000

10,000

220

225

230

AE07

Southpits

50-100

200

205

210

215

0 25 50 75 100

low: 215.8 m (2/2003)

Skiatook Lake levelshigh: 219.1 m (3/2004)

1670

1950

10,800??

TDS (mg/L)

10,000

2,000

10,000

200

205

210

215

0 25 50 75 100

low: 215.8 m (2/2003)

Skiatook Lake levelshigh: 219.1 m (3/2004)

1670

1950

10,800??

TDS (mg/L)

10,000

2,000

10,000

200

205

210

215

0 25 50 75 100

low: 215.8 m (2/2003)

Skiatook Lake levelshigh: 219.1 m (3/2004)

1670

1950

10,800??

TDS (mg/L)

10,000

2,000

10,000

AA06AE51

AA01AA02

North

SkiatookLake

DRY

salt scar erosion

AE13AA61

AA04

16,10022,400

4720

9,700

19,100

29,900

11,3004810

20,000

15,000

15,000

10,000

AA06AE51

AA01AA02

North

SkiatookLake

DRY

salt scar erosion

AE13AA61

AA04

16,10022,400

4720

9,700

19,100

29,900

11,3004810

20,000

15,000

15,000

10,000

4.2

1.7

0.3

1.4

6.9

0.1

1.2

1.0

9.94.2

Tritium (in T.U.)

200

205

210

215

220

225

230

0 25 50 75 100 125 150 175 200 225

Distance along traverse, in meters

Alt

itu

de,

in m

eter

s ab

ove

sea

leve

l

AE07

South

AA06AE51

AA01AA02

AE06AA10AE55

North

SkiatookLake

DRY

brinepits

salt scar erosion

low: 215.8 m (2/2003)

Skiatook Lake levelshigh: 219.1 m (3/2004)

AE13AA61

AA04

~5~20

39730

92023

12,300420

15,300470

2,9604.5

207520

6,060150

9,84050418,400

365

10,000

6,23096

6,500180

18,300375

??

3,35019

a-a’ traverse

15,000

10,0005,000

5,000

2,500

chloride (mg/L)sulfate (mg/L)

AA-01deep

0.01

0.1

1

10

100

1000

10000

100000

2/02 8/02 2/03 8/03 2/04 8/04 2/05

mg

/L

TDS

Cl

Ca

Na

HCO3

acet

DOC

Fe

Mn

SO4

BTEX

AA-02deep

0.01

0.1

1

10

100

1000

10000

2/02 8/02 2/03 8/03 2/04 8/04 2/05

mg

/L

TDS

HCO3

SO4

Na

Cl

Ca

DOC

Fe

Mn

acet

BTEX

W-E traverse

200

205

210

215

220

225

230

0 30 60 90 120 150 180 210 240

Distance along traverse, in meters

Alt

itu

de,

in m

eter

s ab

ove

sea

leve

l

AA13

Southwest

AA08

AE53AA06

AA07AA05

Southeast

salt scar erosion

low: 215.8m (2/2003)

c c''c'

AA09

AA61AE13Skiatook Lake levels

high: 219.1m (3/2004)

53363

49677

53394

6,40019

6,950883

6,860586

18,300376

18,400365

681,460

6,820363

481,280

1,4601310

4,080200

6,060150

9,840504

Chloride(mg/L)Sulfate (mg/L)

SO4 > Cl

SO4 > Cl

2,500

5,000

15,000

10,000

0

0.01

0.02

0.03

0.04

0.05

0.06

10 100 1000 10000 100000 1000000TDS (mg/L)

Br/

Cl

A site B siteoil wells gwSkiatook L.sea water

AE-06

AE-06

AE-05AE-06

AE-07 AE-12AE-12

0.000001

0.0001

0.01

1

100

10 100 1000 10000 100000 1000000

TDS (mg/L)

SO

4/C

l

A site B siteoil wells gwSkiatook L.sea water

OSPER Site A (S Isotopes; Feb 05)

-30

-20

-10

0

10

20

30

40

0 0.005 0.01 0.015 0.02

1/SO4

d 34S

(per

mil)

Gypsum

-10

-8

-6

-4

-2

0

2

0 40,000 80,000 120,000 160,000 200,000TDS (mg/L)

De

lG (

Kc

al/m

ol)

B siteA siteoil wells gwSkiatook L.

2FeS2 + 7O2 + 2H2O 2Fe++ + 4SO4- - + 4H+ (1)

FeS2 + 2NO3- + 2H2O Fe++ + 2SO4

- - + 4H+ + N2 (2)CH3COO- + SO4

- - 2HCO3- + HS - (3)

Fe++ + HS - FeS + H+ (4)Ca++ + SO4

- - + 2H2O CaSO4.2H2O (5)

Mineral-Water Interactions for S at OSPERs

Summary and Conclusions

At OSPER ‘A’ site:1) GW plume (3,000-30,000 mg/l TDS) extends beyond the

salt scarred area & intersects Skiatook Lake; 3-D limits??2) The extent of inorganic and organic GW plumes are

different. 3) Salt & organics from produced water releases still remain

in soils and GW after 65+ years of natural attenuation.

Future Plans Natural attenuation; solute transport (overland &GW);

remediation.

*** Environmental Geosciences, 2005, v. 12, No. 2 ***