Remediation of a CHC site - Planning and project management

The project

Location: Canton of Zurich
Customer: Private person
Phases: Remediation project, submission, remediation
Duration: 2016 - current
Building costs: --

 

As a result of many years of operating a dry-cleaning facility, chlorinated hydrocarbons (CHCs) were found to contaminate the subsoil of a private property. The site had to be remediated due to contaminated groundwater. Remediation was carried out by excavation within the framework of a construction project.
Ecosens supported the customer by developing the remediation project, submitting it and carrying out the remediation work. Major challenges took the form of restricted space and occupational health and safety in the middle of a residential area.

 

Our services

  • Development of the remediation project as well as an implementation and disposal concept. Due to many years of experience in handling CHC sites, Ecosens was able to develop an effective, technically feasible and economical remediation project that was accepted by all parties.
  • Support of the customer during the tender procedures for the work
  • Project management for contaminated site remediation: No space for intermediate excavation storage. The contaminated material was excavated and removed as quickly as possible by taking prior material test samples and loading the material directly. This required the close cooperation of all participants (coordination of excavation and securing the excavation pit with an anchored retaining wall)
  • Development of an occupational safety concept. Occupational safety and protection against harmful emissions were of the highest priority. The excavation pit was covered by a tent to protect the residents of nearby neighbouring buildings from emissions. The tent was equipped with an efficient ventilation system that filtered exhaust air on site using activated charcoal. The occupational safety of the persons in the tent was ensured by protective suits, face masks and protective goggles as well as ventilation and extensive safeguarding of the excavation pit
  • Interface between cantonal authorities, the customer and contractor

Challenges

  • Development of a remediation project for strong contamination with chlorinated solvents that extended down to the bedrock
  • Excavation remediation of problematic hazardous materials in the middle of a residential area under highly restricted space conditions at the construction site
  • Proximity to an adjacent railway line (stability of the excavation pit)
  • Ensuring occupational health and safety for the workers involved as well as emission protection for the population
  • Regulatory cost allocation: Cost allocation by various parties required detailed documentation and examination of the remediation work at each step

Project manager:

Michael Rüffer Partner, divisional manager for contaminated sites
Dipl. Phil.II, Geologist, Hydrogeology CHYN
mrueffer@ecosens.ch +41 44 839 47 81 More

Julia Hunziker Project team member: Contaminated Sites
MSc Environmental Sciences ETH (Federal Institute of Technology)
jhunziker@ecosens.ch +41 44 839 43 More