FOR THE ENVIRONMENT
IN THE CONTEXT OF COUNCIL DIRECTIVE 96/82/EC
Typical Accident 2: Discharge of Very Toxic for the environment substance
Date / Place: December 15, 1974. Hattiesburg, Mississippi, U.S.A.
Substance(s) involved: Pentachlorophenol (PCP). This substance is classified as
very toxic for the aquatic environment and persistent, i.e. N; R50/53.Quantities released / Quantities stored or transported: Not specified.
Description: Discharge of pentachlorophenol into a lake and a river, due to the
unexpected overflow of a wastewater pond13.Consequences: Large numbers of fish killed and many fish species were affected.
It was noted that fish remained contaminated for at least 6 months. PCP was
found in the sediment and leaf litter 18months after the incident.
Lessons learned: The following lessons can be learned from the accident:
a) Type of substance. The substance involved in the accident was pentachlorophenol, an R50/53substance. PCP has been involved in some accidents with very severe consequences for the aquatic environment. The lethal concentration of PCP for various species is very low (e.g. LC50 for rainbow troutis 0.093 mg/l for 48 hr), which means that even small quantities discharged in the aquatic environment can have significant effects on the aquatic habitats. Substances from the same category havebeen involved in many environmental accidents.
b) Route of contamination. Discharge from a wastewater pond or system is another important route of contamination (see also accidents 1, 4, 5 and 26in Appendix 1). This has to be taken into consideration in the design of the sewage and wastewater system of the establishment.
c) Extent of consequences. Not only the consequences of theaccident were devastating, but the recovery period was rather long (due to the persistence of the toxicity of the substance).
Typical Accident 3: Discharge of Very Toxic for the environment substance...