Soil and groundwater contamination caused by 20.000 – 30.000 L of transformer oil leaking into the underground. Dimension: ca. 10.000 m² (Pollutant flag/groundwater), thereof  ca. 4.000 m² and ca. 500 m² / 2000 m³ in the unsaturated soil zone

Multiphase investigation measures using percussion drilling and installation of groundwater monitoring wells as well as determining the current and historical groundwater currents, preparation and implementation of a remediation plan.

Hydraulic In Situ-remediation technology using hydraulic soil washing (unsaturated soil zone, ca. 55 infiltration pipes) with cleaned groundwater, warm water (heated with solar energy)and mixing with H2O2 as well as Pump & Treat using 3 groundwater remediation wells with oil phase removal in 3 wells and 3 stand pipes; Remediation container with soil washing- and groundwater remediation container (3 gravel filters, 2 Activated-carbon filters); leaching of the water into the underground using a drainage shaft.

Oil recovery: ca. 12.000 L Transformer oil
Remediation duration: 1,5 years, planned remediation duration: ca. 5 years

July – Sep. 2002 First Phase of Investigation
Oct. 2002 – March 2003 Second phase of investigation, preparation of Remediation plan
April – July 2004 Third phase of investigation
July – Nov. 2007 Installation of Remediation equipment, Installation of the Remediation container

since Nov. 2007 Operation of the Remediation container