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Field test 1 and Field test 2 (UMWELTSCHUTZ NORD)

The objective of the field tests ist the realization of in-situ bioremediation processes on contaminated sites considering the pilot scale results.

In the two field tests, the model scaling properties from the pilot scale compared to the field scale will be checked.

The field tests for the in-situ bioremediation are done on a site contaminated with heating oil (TPH, Field test 1) and on a site contaminated with Poly-Aromatic Hydrocarbons (PAH, Field test 2) both in southwest Germany.

For enhancing natural activity of microbes, water- enriched with nutrients an hydrogen peroxide- is infiltrated into the saturated zone. Contaminated groundwater is pumped and treated in a water treatment plant.

During the experimental phase of the field tests different chemical-physical, biological, soil and process parameters, necessary for the simulation of the degradation process, were analysed. The project profiles of the two field tests are summarized in the table below:

Table 2: Project Colombo – Project profiles Field test 1 and Field test 2

Field test 1 / Field test 2
Contaminant: Heating oil / Contaminant: PAH
Source of contamination: Leakage in a pipeline / Source of contamination: unknown
Contaminated area: 40,000 m² / Contaminated area: 12,000 m²
Level of contamination (average): 10,000 mg/kg TS / Level of contamination (average): 11,000 mg/kg TS (Naphthalene 32 %)
Contaminated depth: 99.0 – 97.5 m
above sealevel / Contaminated depth: 79.5 – 76.0 m
above sealevel
Groundwater level: 98.5 – 98 m
above sealevel / Groundwater level: 92.0 m
above sealevel
Coefficient of hydraulic conductivity (Kf) 3 x 10-4 m/sec / Coefficient of hydraulic conductivity (Kf) 5 x 10-4 m/sec
Colombo field area: 1,040 m²
Infiltration wells 18
Remedial wells 7
Observation wells 6 / Colombo field area: appr. 400 m²
Infiltration wells 10
Remedial wells 4
Observation wells 11
(total field)
Start in-situ bioremediation 1st December 1996 / Start in-situ bioremediation 1st January 1996
Duration in-situ bioremediation: 4 years / Duration in-situ bioremediation: 4 years

specific terms

in-situ bioremediation, biodegradation of TPH, biodegradation of PAH, hydraulic in-situ remediation