The Natural Catch Tobias Praamstra MSc Consultant In situ soil [PDF]

SLIDE 1

The Natural Catch

Tobias Praamstra MSc Consultant In situ soil remediation Tauw Netherlands

SLIDE 2

Case landfill Kanaalpolder

Philippine
1967- 1977
500.000 m³
Chemical waste
On sand

SLIDE 3

What is the problem?

1 2 5 8 7 4 3

B08

6

10

16 15 12 13 105 9 106 11 104

1 2 5 8 7 4 3

B08

6

10

16 15 12 13 105 9 106 11 104

Large plume
Seapage water on surface level
Bad smell
Risks
Benzene
Ethylbenzene
Monochlorobenzene
Vinylchloride
Chloroethane
Dichloroethane
Range: 100 – 10.000 µg/l

SLIDE 4

Nature as mentor

Two chemical landfills, two green principles

Volgermeerpolder within a peat land Stededijkpolder with circular ditch

SLIDE 5

What’s the basic idea of the concept?

Non-conventional approach: use and optimize natural

attenuation processes for a finite solution by

Using the landfill and part of soil as (bio)chemical reactor
Drainage of migrating contaminants (catch 1), and
Adsorption by (local) natural (rest) products (catch 2)
Aerobic and photochemical degradation (catch 3)

SLIDE 6

Combination: Natural Catch

Discharge purified water Drainage Landfill Percolate Adsorption Biological & photochemical degradation Liner or clay Peat filter O2 / UV Soil passage Discharge purified water Drainage Landfill Percolate Adsorption Biological & photochemical degradation Liner or clay Peat filter O2 / UV Soil passage

Nature does the work 1 Rainwater leaching 2 anaerobic biodegradation 3 filtering during soil passage 4 adsorption in peat filter 5 aerobic and photochemical (bio)degradation in circular canal

SLIDE 7

Preconditions natural catch

Contaminants which can be adsorbed and/or degraded

(biological or photochemical)

Enough space for implementation
Conductive and ‘inert’ adsorption medium
Right dimensions of circular ditch and extraction rate

drainage and hydraulic residence time

SLIDE 8

Laboratory tests

Closed water reservoir Continuous water head Test material Glass pearls Flow measurement Cap with hole

Conductivity and adsorption

SLIDE 9

The field pilots

Dimensioning:

Hydrology
Residence time
Flow
Layer thickness

Implementation:

2 pilots

Period:

Nov 2009-Jul 2011 Green compost Peat

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Pilot phase 1: physical feasibility

Phase 1

Extraction flow rate
Draining function
Adsorption medium
Water quality

Conclusions:

Both ditches drained
Green compost degrades
Flow 2-4 m3/d

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Pilot phase 2: processes qualified

Phase 2

Adsorption in peat: contaminants build up gradually
Aerobic biological degradation: DNA analyses

(coding genes enzymes)

Oxygen detection surface water: 10 mg/l

Vinylchloride Dichloroethane

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Pilot phase 3: processes quantified

Phase 3

Final samples of surface- and groundwater
Evaporation measurements
Mass balances: insight in contribution NA-mechanisms

Groundwater upstream

1 10 100 1000 10000 100000 14-10-2009 22-1-2010 2-5-2010 10-8-2010 18-11-2010 26-2-2011 6-6-2011 14-9-2011

Time (date) Concentration (ug/l)

1,1-Dichloorethaan Monochloorethaan Vinylchloride

Natural catch surface water

1 10 100 1000 10000 100000 14-10-2009 22-1-2010 2-5-2010 10-8-2010 18-11-2010 26-2-2011 6-6-2011 14-9-2011

Time (date) Concentration (ug/l)

1,1-Dichloroethane Monochloroethane Vinylchloride

93 – 100 % efficiency

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Pilot phase 3 (2)

Lindvall method

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Pilot phase 3 (3)

Mass balance (fluxes)

Q groundwater – Q ditch water = Q sink Q sink = Q degradation + Q evaporation

Component Sink flux measured (g/d) Aerobic degradation flux calc lit (g/d) Evaporation flux calculated (g/d) Evaporation flux measured (g/d) Benzene 0,41 0,44

0,03

0,0006 1,1-DCA 4,0 3,72 0,28 0,0023 Monochlorobenzene 4,4 4,35 0,05 0,0026 Monochloroethane 52 50,35 1,65 2,65 Vinylchloride 0,12 0,12 <0,0016

+ Q adsorption

SLIDE 15

Conclusions pilot research

The natural catch works, if well dimensioned 1 Rainwater leaching 2 anaerobic biodegradation 3 filtering during soil passage 4 adsorption in peat filter 5 aerobic and photochemical (bio)degradation in circular canal 93 to 100% purification anaerobic leachate (4 & 5)

Inspired by

Discharge purified water Drainage Landfill Percolate Adsorption Biological & photochemical degradation Liner or clay Peat filter O2 / UV Soil passage Discharge purified water Drainage Landfill Percolate Adsorption Biological & photochemical degradation Liner or clay Peat filter O2 / UV Soil passage

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Advantages of peat filter within concept

Adsorption and preventing shock loads (buffering)
Creating a habitat for hydrocarbon degrading micro-
rganisms and eventually for water vegetation
Smaller carbon footprint in relation to activated carbon filter

(production, transport)

(Experimental: purification possibility of loaded, contaminated

peat with e.g. white-rot fungus)

Inspired by

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Advantage of total concept Natural Catch

Landfill Impermeable layer Sheet piles Extraction Landfill Impermeable layer Sheet piles Extraction

No ‘intensive care’ No more non-durable top sealing on, or sheet piling around, chemical landfills, and/or energy consuming pump & treat A finite solution for chemical landfills Landfill as a reactor, not as a sarcophagus

Inspired by

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Prospects

Feasible for landfills and remote contaminated areas

(limited maintenance, one pump on wind or solar energy). Winner Nicole Technology Award

Use of ‘inert’ local and natural adsorption material

(modified peat, crushed coffee/cacao been shells, crushed moringa seeds, etc)

Use in hybrid for purification hospital wastewater

(instead of high tech purification plant). Winner Award Watership Vallei&Veluwe

SLIDE 19

Acknowledgements Kanaalpolder

Initiators:

Thanks to colleagues of Tauw & Witteveen & Bos