A new start
After the pause, the project team hired new partners to execute the remediation. Besides setting up new work protocols, biomonitoring become part and parcel of the work regime on the site.
Text by Linda Bergsten, illustration by Ikonaut, photos by Gregory Collavini
The four companies that make up the ARGE MZ Hueningen consortium with details of the respective shares.
Published on 01/07/2021
The project to resume remediation was put out to tender. The project team at Novartis selected a joint venture, ARGE MZ Hueningen, comprising the companies Marti AG, Marti Infra AG, Züblin Umwelttechnik GmbH and Strabag Umwelttechnik GmbH.
The remediation project team established a revised project organization with clearly defined roles and responsibilities. The project team also defined additional internal resources including HSE, finance and communication, to ensure the necessary expertise and resources were aligned to resume remedial activities. These steps guaranteed both better cohesion between the various disciplines and a team of experts on whom the project director and the steering committee could rely. Supervision of the operation became more transparent. In particular, corrective measures could be implemented more rapidly.
ERM GmbH was selected to manage site control and coordination, including coordination with Novartis HSE. Together with Novartis HSE, ERM developed a detailed health and safety program before the remediation work recommenced. ERM had the day-to-day HSE responsibility on the site; Novartis HSE conducted weekly health and safety walkthroughs of the site, which had already been in place prior to the shutdown.
Three safety zones
Three different safety zones were established throughout the site (white, gray and black). A different degree of personal protective equipment (PPE) was worn in each zone. This practice was the same as initially implemented in the project.
In the white zone, where the offices were located, no particular PPE was worn. In the gray zone – the general remediation area – workers wore PPE such as hard hats, steel-capped shoes and long-sleeved clothing. In the contaminated black zone, workers were equipped with breathing apparatus or self-contained equipment.
Remediation involved several high-risk activities, such as working at heights, working in confined spaces and conducting earthworks. At the peak of the remediation work, nine people were working inside the tents operating different machinery (excavators and dumpers). Most of the time, however, two to three people were working inside the tents operating the earthwork machinery.
STEIH site following the restart of the remediation work.
To ensure that no workers were affected by working with soil and dust containing HCH and its breakdown products, a biomonitoring program was set up at the beginning of the project and redesigned after the events of 2013. Blood and urine of workers was collected and analyzed as is common practice at remediation sites in Switzerland.
In redesigning the biomonitoring program, the team, comprising the Swiss National Accident Insurance Fund Suva in coordination with the occupational physicians of all the companies involved at the remediation site, reviewed the dust monitoring results and decided that the program should include the four main isomers of HCH as well as its breakdown products, in particular TCB. However, as no reliable method existed for TCB, it was decided that the urine samples should be analyzed for TCB’s metabolite product trichlorophenol (TCP). This choice was validated by a group of international scientists from several universities in Europe, and reference values recommended by French National Research and Safety Institute for the Prevention of Occupational Accidents and Diseases (INRS) were used.
Additionally, background values for unaffected populations were identified from the Fresenius Journal of Analytical Chemistry and the German Environment Agency (Umweltbundesamt, UBA). Together with the INRS values and the different half-life values of the molecules, a “traffic light” system was implemented (green, amber and red). If the result of a worker’s urine analysis for TCP was below the environmental threshold, it was considered green; if the result was higher than the INRS value, it was considered red. With this traffic light system in place, each worker could be monitored and assessed, and trends could be reviewed. For example, if a worker had elevated urine levels, his or her working methods were reviewed by an industrial hygienist and a physician, and measures were implemented to prevent the problem – e.g. ill-fitting PPE – from occurring again. If the results were red, the work had to be stopped immediately.
Sampling of urine and blood was conducted monthly for all workers on the site, including workers who never entered the highly contaminated area (black zone). After reviewing the results, the sampling schedule was later adapted to a risk-based sampling strategy, with monthly samples for workers entering the black zone and quarterly samples for workers outside this area.
