1. Introduction
2. An industry-standard event? Schweizerhalle and the environmental impact of the Basel chemical industry
3. The major fire at Schweizerhalle: The inferno of flames on November 1, 1986, and its consequences to this day
3.1. The Sandoz fire site: A threat to the drinking water of 200,000 people
3.2. Ground and drinking water investigations after Schweizerhalle: Sought-after, ignored, and disturbing pollutants
3.3. The failed remediation: How the Schweizerhalle landfill came into being
4. Up to 1000 times less sensitive than 25 years ago: The development of analytical technology at Ciba SC and Novartis
5. When chemical and pharmaceutical companies are caught up by their waste: The landfills of the Basel chemical industry
5.1. Up to 7000 substances in the landfills: The ignored variety of pollutants
5.2. Overlooked pollutant diversity I: The supposedly clean groundwater at Letten in Hagenthal-le-Bas
5.3. Overlooked pollutant diversity II: Data mountains for the drawer in the case of the Muttenz chemical waste landfill
5.4. Overlooked pollutant diversity III: How technical control of chemical waste fails in Bonfol
5.5. Overlooked pollutant diversity IV: Half-measures for the Hirschacker pit in Grenzach-Wyhlen
5.6. Blind spots at the top environmental authority: The questionable handling of rankings, screenings, and unknown substances by BAFU
6. Conclusion.