Advanced Techniquefor Improving the Biological Quality

of Petroleum-contaminated Soils

National Petroleum Technology OfficeTulsa, OK

Nancy Comstock, Program Manager

FEAC317

Art Stewart, Principle Investigator

Landfarming operations . . .

“. . . highly effective in converting contaminated soil into material that can be used beneficially at approved locations on the military installation in revegetativeand soil restoration projects.” (Fort Polk)

“. . . the Landfarm has safely treated in excess of 1800 tons of POL-contaminated soil and 600 tons of digested sewage sludge in the past two years alone. RESULT: Annual cost savings in excess of $250 K.” (Fort Sill)

Advanced Technique . . .

The central idea: use known properties of biological systems to facilitate the ecological recovery of oily soil habitats.

-- Hasten the rate of oil biodegradation in oily soils. -- Make biodegradation of TPH more complete. -- Attend to soil physical-property concerns. -- Produce a soil product of demonstrably good

biological quality.

Advanced Technique . . .

earthworms

plantsplantsplants

Experiments with oily soil from a landfarming operation in northwest Colorado.

-- Can earthworms live, grow and reproduce in the oily soil?

-- How “bad” is the oily soil, compared to non-oily soil?

-- Can organic amendments be used to improve earthworm performance in oily soil?

0

10

20

30

40

50

60

70

80

0 20 40 60 80 100 120

Test soil concentration (%)

Eisenia

pre

fere

nce

for t

est s

oil (

%)

24-h response

Earthworms can tell the difference!

Soil/amend Surv. (%) Reps w/ repro No. of Juveniles

Art + 0 90 9/9 299

LS + 0 90 0/9 0

LS + HM 80 3/3 17

LS + CM 60 1/6 1

LS + SM 100 4/10 19

LS + TF 90 0/9 0

LS + TP 80 0/9 0

Responses of Eisenia to organic amendments in oily soil

1. Eisenia can detect (and behaviorally avoid) oily landfarm soil.

2. The non-amended landfarm soil seems near-satisfactory, in terms of being able to sustain earthworm populations.

3. The type of organic material used as an oily-soil amendment makes a difference to Eisenia.

4. At least some species of plants can germinate and grow in the oily landfarm soil.

5. Gypsum (CaSO4), added at five times the highest recommended rate, does not significantly lighten

landfarm soil color (Munsell chart).

Future accomplishments --

Field- (or greenhouse) scale testing

-- Effects of plant – soil invertebrate linkages onrate and extent of ecological recovery.

-- Relationship between bulking agents and soil biological quality, for oily landfarm soils.

Biological Quality of Soils Containing Hydrocarbons and Efficacy of Ecological

Risk Reduction by Bioremediation Alternatives

FEAC303

Dexter Sutterfield, Program Manager

National Petroleum Technology Office

Tulsa, OK

Art Stewart, Principle Investigator

Biological Quality of Soils . . .

• Project began in 1995.

• PERF project 94-06, “Environmentally Acceptable Treatment Endpoints for Hydrocarbon-Contaminated Soils”.

• Collaborative research on 20 soils.

• Understand mechanisms that retard the release of petroleum hydrocarbons from soil.

• Characterize soil biological quality.

Biological Quality of Soils . . .

Can soil toxicity be predicted from total petroleumhydrocarbon (TPH) concentration?

Does sequestration of TPH compounds by soil reduce THP ecological risk?

Questions relate to regulations that can affect land-use alternatives for sites with petroleum-contaminated soils.

Perspective: Increasingly, environmental regulatorydecisions are being on the basis of risk to human healthand ecological health.

Biological Quality of Soils . . .

Eisenia foedida survival, growth and reproduction.14-d tests, using various concentrations of the oily soils.

Contaminated soil concentration

Eart

hwor

m

resp

onse

Biological Quality of Soils . . .

Two not-so-hidden project agendas

1. Learn about petroleum industry perspectives on petroleum industry environmental problems.

2. Transfer ORNL expertise and perspectives in ERA to petroleum industry representatives.

Ecological risk –

What is it? How do we use it? How do we avoid it . . .?

Glenn W. Suter, III -- A framework for assessing ecological risks of petroleum-derived materials in soil.

Rebecca Efroymson – Toxicity benchmarks for petroleum hydrocarbons to soil invertebrates and plants.

Biological Quality of Soils . . .

0%

20%

40%

60%

80%

100%

10 100 1000 10000 100000 1000000

Total Petroleum Hydrocarbons (mg/kg soil)

Perc

en

tile

SOILINVERTEBRATE

PLANT

Efroymson et al. 2000

Guillermo Napolitano – 1998. Characterization of petroleum-contaminated soils by thin-layer chromatography with flame ionization detection. J. Soil. Contam. 7:709-724.

saturates

aromatics

resins

asphaltenes

12 0

cm6

Biological Quality of Soils . . .

Tested sampling methods that might be used to provide data on biological conditions at sites where soils maycontain petroleum hydrocarbons.

-- Depot/transfer site near Salt Lake City, Utah.

-- Small E&P site in south-central Kentucky.

Biological Quality of Soils . . .

Hyperspectral analyses

Spatially explicit modeling

Restoration of landfarm soils