Download - Phytoremediation of phc & salt 2011 Dr Greenberg

Phytoremediation of petroleum and salt

impacted soils: Successfully meeting

generic Tier 1 standards and making green

technologies work

Bruce Greenberg, X-D Huang, K Gerhardt, X-M Yu, S Liddycoat, X Lu, B

McCallum, G MacNeill, M Hannaberg, P Mosley, J Gurska, N Knezevich,

P Gerwing and B Chubb

Partners: Cenovus; ConocoPhillips; Lone Pine Resources; Baytex; TransEuro

Energy; Solaction; Shell; Talisman; PennWest; Questerre Beaver River; Imperial Oil;

Seaway Energy Services; MWH; SNC Lavalin; NSERC

EARTHMASTER ENVIRONMENTAL

STRATEGIES INC.

Outline

1. Overview of phytoremediation

2. Science of successful phytoremediation

3. Examples of full scale phytoremediation at

petroleum and salt impacted sites

4. Achieving Tier 1 and Tier 2 Criteria

Phytoremediation Processes

• Volatilization

• Phytodegradation

• Chelation/compartment in leaves

• Translocation: root symplast

xylem

• Chelation/compartment in roots

• Plant uptake soilroot

• Rhizosphere Processes

• Bioavailability particlewaterRhizodegradation - PHC

Salt

1. Improves the quality of soil

2. It is driven by solar energy and suitable to most regions

and climates

3. It is cost effective and technically feasible

4. Plants provide sufficient biomass for rapid remediation; promote

high rhizosphere activity

5. Reasonable time frames - 2 to 3 years

6. Can be used effectively at remote sites

7. Greenhouse gas storage: 6 tonnes per ha per year

8. Effective for remediation of PHC and salt – relevant to the energy

industry

Advantages of Phytoremediation

Development, Proof, and Full Scale Application of

PGPR Enhanced Phytoremediation Systems (PEPS)

Over 12 years of research with full-scale field

remediations at each stage of development and

application

1. PHC: sites in AB, BC, QC, MB, NWT and ON

(2004-11)

2. Salt: sites in SK, AB and NWT (2007-11)

Performing full scale remediations for > 5 yrs

PEPS successful at > 25 sites

The key to phytoremediation success -Transfer of the science from the lab to the field


STRATEGIES INC.

1. Strategies for aggressive plant growth in impacted and

poor quality soils at full scale sites

– PEPS Deployment by highly trained scientists

2. Monitoring the progress of phytoremediation at each

site – Following the chemistry

3. Continuous improvement of our phytoremediation

systems through scientific research

WEBi-Earthmaster-UW partnership


STRATEGIES INC.

• Synergistic expertise in contaminated site remediation

• Developed commercial phytoremediation

technologies (PEPS)

• 12 years of research, development and full scale field

implementation

• Field proven systems

• Research to continually improve PEPS

Edson, AB – Before treatment

Soil Impact – PHC (Diesel Invert; 85% F3)

Job # 1 – Grow plants using PEPS

PEPS Deployment at Edson, AB


Mission Accomplished - excellent plant growth

Dawson, BC – Before PEPS treatment

Soil Impact – PHC (75% F3)

Dawson after PEPS deployment – excellent plant growth

Soil Impact – PHC (75 % F3)

Weyburn, SK - 1: Before PEPS

Soil Impact – Salt (ECe ~ 15 dS/m)

Weyburn, SK - 1: PEPS utilization – 1 Month


Roots

5 cm

Weyburn, SK - 1: PEPS utilization – 3 Months


Weyburn, SK - 2: Before PEPS deployment


Weyburn, SK - 2: PEPS deployment – One month


Weyburn, SK - 2: PEPS deployment – 3 Months

Average NaCl in leaf tissue = 23 g/kg


500 kg of salt (NaCl) off the site in the plants

That is equal to the weight of a cow!

PGPR Enhanced Phytoremediation Systems (PEPS)

Aggressive plant growth strategies leads to remediation

Physical soil treatment: site preparation, site preparation, site

preparation

Phytoremediation: Growth of plants with PGPR

Monitoring and remediation assessment: Environmentalchemistry to follow PEPS from start–to–finish

• PGPR: Plant growth promoting rhizobacteria.

• Prevent the synthesis of stress ethylene.

• PGPR are applied to the grass seeds prior to sowing

NOT Bioaugmentation

• Effect depth of remediation ~ 0.5 m

Interaction of a PGPR Containing ACC

Deaminase with a Plant Seed or Root

Plant growth promoting rhizobacteria (PGPR)

Natural, non-pathogenic strains of PGPR (usually Pseudomonads)

We have isolated PGPRs from ON, AB, SK

and the NWT

PGPR are applied to seeds prior to planting

Stress Response

Ethylene

ACC Synthase

ACC Oxidase

Ammonia and -ketobutyrate

ACC Deaminase

Plant Tissue

Bacterium

Exudation

Amino Acids

ACC ACC

IAA IAA

SAM

Amino Acids

Cell Elongation and Proliferation

With abundant plant growth – PEPS results

in PHC Remediation

• At least twice as much plant biomass due to PGPR; root growth to 50

cm below ground level

• Remediation monitored using CCME PHC analytical methods

• 30 to 40% remediation per year with PEPS; Twice as fast as plants

without PGPR

• Rhizosphere microbes (esp. PHC degraders) elevated 10 to 100 fold

with the PEPS - microbes and plants consume PHC

• Very low 14C detected in soil microbial fatty acids – Carbon came

from PHC metabolism (PHC has no 14C)

• Very low 14C in CO2 that evolves from soil – PHC has been

mineralized to CO2

• No PHC detected in plant tissue as it disappears from the soil

• Tier 1 criteria (and closure) have been met at several full scale sites

sites

Phytoremediation of PHC

oil

droplet

O2

oxidized

PHC

A

1 µm

PHC

PHC-degrading

microbes

[O] DEHYD

[O] ω-OxGenase

[O] ω-OxGenase

Cn PHC

Rhizo.

cell membrane

(width C30 to C40)

Cytosol

OHOH

O

HH

Cn fatty

acid

B

O

OH

O

OH

O

(A) Microbial aerobic PHC degradation – rhizosphere supported by plants

(B) Possible microbial oxygenation pathway of PHC to form a fatty acid

Acetate

-oxidation

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

1 3 5 7 9 11 13 15 17 19 21 23 25

To

tal P

HC

(%

)

Sampling points

Jun-07 Oct-07 Jun-08 Oct-08

Total

31%

average

In June 2007, 9 of 13 sampling points above Tier 1 criteria (F3 > 1300 mg/kg)

Edson, AB – PHC Remediation (2007- 08)


0

500

1000

1500

2000

2500

3000

3500

LTA 1 LTA 3 LTA 5 LTA 7 LTA 9 LTA 16 LTA 17 LTA 19 LTA 21 Average

F3 (

mg

/kg

)

Sampling points

Series1

Series2

31%

Alberta F3

Tier 1 Criteria

•Remediation goals were met

•No points over Alberta Tier 1 criteria

June 07

Oct 08

Edson, AB – PHC Remediation (2007- 08)


1 2 3 4 5 6 7 8 9 Average

Soil Impact – PHC

Soil sampling point

sump

5

11

8

7

6

4

3

2

12 10

1

9

35 m

2 m

2 m

6 m

6 m

6 m

6 m

6 m

6 m 3 m

20 m

4 m

15 13

16 14

2 m 2 m 2 m

3.5 m

3.5 m

3.5 m

Planted un-impacted plot

1 m

Impacted Plot

Un-impacted Plot

Swan Hills, AB – End of Season (2009 – 10)

0

500

1000

1500

2000

2500

3000

3500

4000

4500

1 3 4 5 7 8 9 12 Average 13 16 Average

F3 (

mg

/kg

)

June 2009

October 2009

September 2010

0

500

1000

1500

2000

2500

1 3 4 5 7 8 9 12 Average 13 16 Average

F2 (

mg

/kg

)

June 2009

October 2009

September 2010

65% remediation

F2 & F3 analysis

performed by

Maxxam. Method

used: cold shake

extraction, enhanced

silica-column clean-up

Alberta

Tier 1

standard

55% remediation

Alberta

Tier 1

standard

Swan Hills, AB – F2/F3 Results

79% remediation

64% remediation

Anomalous sample point

Phytoremediation Cost analysis: Edson Site

• Volume of impacted material – 460 m3 of diesel invert drilling mud

was originally spread over 1.07 ha

• 1.07 ha impacted to a depth of 0.3 m or 3,210 m3 of PHC impacted

material

• The costs for the entire project was: $104,000 or $32.50/m3

• Includes all Earthmaster, WEBi and 3rd party costs

• Costs about the same at remote sites

• Unit cost drops as volume of impacted soil increases

• Landfilling this material would have cost at least $80/m3

• 2 h truck turnaround time

• Costs increase dramatically as the site becomes more remote

Conclusions for PHC Remediation

SUCCESS

• Achieved PHC remediation: 5 sites brought to closure, 11

second generation sites progressing well towards closure

PERFORMANCE PREDICTIONS FOR PEPS

• Fine grain soils - F3 from 2000 to 10,000 mg/kg

• In 2 to 4 years, will meet Alberta Tier 1 standards

• Fine grain soils - F3 above 10,000 mg/kg

• In 3 to 6 years, will meet Alberta Tier 1 or 2 standards

• Coarse grain soils - F3 above 3000 mg/kg

• Phytoremediation will significantly lower F3

• Tier 2 approach may be required

COST

• Actual cost for the Edson site (3,400 m3) was $33/m3

• Cost to landfill (landfill 1 h from site): at least $80/m3

PEPS use at

Salt Impacted Sites


STRATEGIES INC.

Plant responses to salinity

• Inhibited germination

• Decreased water uptake

• Unbalanced sodium/potassium ratios

• Inhibition of photosynthesis

• Increased reactive oxygen species (ROS)

• Increased ethylene production

• PGPR doubles biomass

Norman Wells, NWT – End of Season (2010)

Soil Impact – Salt

AB

C

+ + +- - -

High shale area

Plants used: slender wheatgrass and red fescue

No soil conditioning


Soil Impact – Salt

AB

C

N

High shale area

has filled in 0

1

2

3

4

5

6

7

Tzero (2008) Year 2 (2009) Yeae 3 (2010)E

Ce (

ds/m

)

Plot B

Year 3 (2010)

0

1

2

3

4

5

6

Tzero (2008) Year 2 (2009) Yeae 3 (2010)

EC

e (

ds/m

)

Plot C

Year 3 (2010)

Salt Remediation


0

3

6

9

12

15

18

T zero (2008) Year 2 (2009) Yeae 3 (2010)

EC

e (

ds/m

)

Plot A

Year 3 (2010)

Mass balance proved salt uptake

accounts for drops in ECe

Current Research to Improve PEPS

• Optimize the CCME PHC analytical

protocol to remove interferences from

biogenic organic compounds (BOC)

• Assess soil toxicity during

phytoremediation to meet Tier 2 criteria

During Phytoremediation – Have to assay PHC

without interferences from biogenic organic

compounds (BOCs)

• Ontario MOE sampled at 180 pristine rural and old urban parkland sites

• 218 surface soil samples were selected for PHC analysis

• Only 36 of 218 were ND for F3 (For BC: will be in both and EPHC10-19

and EPHC19-32)

• 8 samples exceeded F3 criteria

• BOCs are primarily derived from plant material – Issue for phytoremediation

Enhanced CCME method for

removal of BOCs

The CCME method recognizes that BOCs will

interfere and leads to a erroneously high PHC

data (particularly F3)

Clean up of extracts with silica gel can be used

to help remove interfering BOC

Proper use of Si cleanup can overcome most of

the problems (e.g., Method 10 in BC)

Two methods: 1. In situ Si treatment

(Standard method)

2. Ex situ Si Column clean-up

(Enhanced BOC clean-up)

GC-FID analysis of PEPS soil samples

with Enhanced BOC Method

No clean up In situ Si gel clean-up Si gel Column clean-up

BOC Some

BOC

removed

Almost

all BOC

removed

Enhanced BOC

Method used in

phytoremediation

GC-MS – Shows only BOC is removed by

the enhanced BOC method

Total ion scan – GC-MS Total ion scan – GC-MS

No clean-up

In situ Si clean-up

Enhanced BOC Method

F2/F3 F3/F4

No clean-up

In situ Si clean-up

Enhanced BOC

Method

Selective ion scan – GC-MS

Ion: 137

Compounds identified:

plant terpenoids and

plant sterols

Plant toxicity testing – to meet Tier 2 criteria

• Plant Species

– Cucumber, Barley,

Northern Wheatgrass

• Endpoints

– Percent Emergence (7d; 14/21d)

– Root and shoot length/weight

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000

No

rma

lize

d A

ver

ag

e E

nd

po

int

Mea

sure

men

t

Petroleum Hydrocarbon F3 Concentration (mg/kg)

Followed Environment Canada plant toxicity test protocol

Environment Canada

Protocol minimum

endpoint

requirements for

artificial soil

Cucumber Root

Weight

Plant toxicity

not correlated

with F3 levels

Will have springtail data shortly

• Proven to work PHC and/or salt impacted sites.

• Remediations at all sites have been successful; > 25 sites.

• Phytoremediation costs < half the cost of landfilling.

• Liability is reduced, not transferred to a landfill.

• Cost effective at remote sites.

• Enhanced CCME BOC method – phytoremediation will meet

Tier 1 criteria.

• Tier 2 approach – will work – After PEPS brings F3 levels ≤

2500 mg/kg (no plant toxicity).

Why Use Phytoremediation?

Thank you


STRATEGIES INC.

Please visit us at the Earthmaster booth

for more information