Summary

Case submitted by: BioSoil
Country: The Netherlands
Built-up site?: No
Soil type: Layered soil, clay/peat/sand
Follow-up required?: Yes, after the excavation the in-situ remediation has started
Treated contamination: Chlorinated Volatile Organic Compounds (CVOC), Mineral oil, Volatile aromats, including benzene (BTEX). The location is a former chemical washery which is heavily contaminated with CVOC. In the surrounding of the location, there is a contamination of mineral oil/BTEX because of oil reservoirs.
Medium contamination: Soil / pure product and groundwater
Dimension contamination: 4780 m3(soil) en 13000 m3 (groundwater)
Remediation goal: Soil and groundwater should reach the Dutch intervention level. For VC, ethyl benzene and xylene there is a divergent remediation level (Maximum Acceptable Concentration (MAC)) based on the potential risk for humans. The MAC level for VC is 4 ug/l, for ethylbenze 77 ug/l and for xylene 54 ug/l.
Remediation goal achieved?: Yes/No. The soil remediation for mineral oil/BTEX and CVOC has succeeded. The CVOC contamination in groundwater exceeds (mainly in the source area) the remediation goal. This is mainly caused by the delayed release out of clay/peat layers that locally possesses pure product.
Initial and final concentration or load removal:
BTEX initial concentration: ? µg/l; final concentration: < 1 µg/l
CVOC initial concentration: 210.000 µg/l;
PER initial concentration: ? µg/l; final concentration: locally > MAC
Active remediation phase: May 1999 until 2007
Passive remediation phase: The passive phase is not yet completed.
Expected realization period: 2007 until unknown
Added reports:
Pilot HIP Amsterdam

Case detailed information

General information
Project name: Amsterdam (Asterweg): CVOC, BTEX and mineral oil*** Case submitted by: BioSoil Contact: Mw. C. v.d. Steenhoven Address: Nijverheidsweg 27 3341 LJ Hendrik Ido Ambacht Telephone number: +31 (0)78-682 01 40 Email-address: c.vandesteen@biosoil.com
Location
Country: The Netherlands City/region/county: Amsterdam, Noord-Holland (future) use of location: office / industrial Built-up location during the active remediation phase?: No
Technique
Explanation technique: Also other remediation techniques applied?: Yes, 3 oil tanks and sewage disposal are removed, and excavation of contaminated soil up to the groundwater level After care needed?: Yes, after the excavation the in-situ remediation has started Rationale for the chosen technique: The goal was the removal of humane and spread risks. In the first phase the direct contact options with the contamination are removed through the removal of oil tanks and the excavation of contaminated soil (above intervention values). Given the nature and distribution of the contaminants (up to 30 m below surface), the second phase of the groundwater treatment up to 30 m below surface is treated with the use of stimulated anaerobic biological degradation of CVOC. There has also been an extraction of groundwater and above ground treatment water for mineral oil / BTEX contaminated water.
Contamination
Treated contaminant(s): Chlorinated Volatile Organic Compounds (CVOC), Mineral oil, Volatile aromats, including benzene (BTEX). The location is a former chemical washery which is heavily contaminated with CVOC. In the surrounding of the location, there is a contamination of mineral oil/BTEX because of oil reservoirs. Contaminant phase: Soil / pure product and groundwater Size contamination: 4780 m3(soil) en 13000 m3 (groundwater) Depth contamination: 30 m below surface
Soil
Soil type: Layered soil, clay/peat/sand Saturated/unsaturated zone?: Saturated and unsaturated zone Permeability: Flow velocity or gradient groundwater:
Result, duration, expense
Remediation goal: Soil and groundwater should reach the Dutch intervention level. For VC, ethyl benzene and xylene there is a divergent remediation level (Maximum Acceptable Concentration (MAC)) based on the potential risk for humans. The MAC level for VC is 4 ug/l, for ethylbenze 77 ug/l and for xylene 54 ug/l. Remediation goal achieved?: Yes/No. The soil remediation for mineral oil/BTEX and CVOC has succeeded. The CVOC contamination in groundwater exceeds (mainly in the source area) the remediation goal. This is mainly caused by the delayed release out of clay/peat layers that locally possesses pure product. Initial and final concentration and load removal: BTEX initial concentration: ? µg/l; final concentration: < 1 µg/l CVOC initial concentration: 210.000 µg/l; PER initial concentration: ? µg/l; final concentration: locally > MAC Active remediation phase: May 1999 until 2007 Passive remediation phase: The passive phase is not yet completed. Expected realization period: 2007 until unknown Total costs passive/after care phase: Total costs active phase:
Stakeholders
Problem owner: Contractor: BioSoil Remediation plan: BioSoil Remediation research: IWACO Competent authority: Milieudienst Amsterdam Contact information stake holders:
Additional information
Lessons learned: First, during the construction of the in-situ system it became clear that the extent of contamination was much larger than expected. Also the subsequent delivery of particularly poorly permeable clay / peat layers appeared to be so high that the remediation goal could not be achieved in all wells. TNO concluded there was no stabile final situation. Locally, the subsequent delivery was larger than the biological degradation, as became evident in rising concentrations after the injection of the electron donor had stopped in 2007. Remarks:
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