Remediation of soil contaminated with persistent organic pollutants in Sumgait, Azerbaijan.

ABSTRACT

The Sumgait remediation project was implemented in 2015 as a partnership between Blacksmith Institute and the site owner Azerikimya Joint Stock Company (Azerikimya) in Sumgait City, Azerbaijan Republic, about 30 km northwest of Baku. The project was financed by the European Commission and supported by the Ministry of Ecology and Natural Resources (MENR) and Sumgait Municipality. The site is a place on the Caspian Sea coast that was formerly an industrial area highly contaminated with various pollutants and particularly benzo(a)pyrene, benzene, and polychlorinated biphenyls (PCBs). As part of initial environmental assessment, the project team took soil samples at 19 locations at the surface and at the depth of 0.5 m. The maximum topsoil benzo(a)pyrene concentration was 76.21 mg/kg, benzene, 121.5 mg/kg, and PCBs, 121.02 mg/kg. The remediation project involved the removal of 804 m3 of contaminated soil and disposal of the contaminated soil at the MENR Hazardous Waste Polyqon (landfill). A comparison of pre- and post-excavation sampling shows that average contaminant levels in soils in the upper 0.5 m were reduced by an average of 97%. These actions were followed by bioremediation activities. More than 13,000 m3 of clean soil and organic fertilizer were placed and leveled over an area of two hectares. Approximately 1200 locally grown native tree species were planted, and a drip irrigation system was installed. The area is now a park close to the beach.