Chemical Characterization of Environmental Samples after Oil Spill in Iguassu River, Parana, Brazil, July/2000

Abstract

ABSTRACT On July 16, 2000, a rupture of a pipeline occurred in the Scraper area of the PETROBRAS refinery located in Araucaria, in the state of Parana, south of Brazil. This resulted in the spill of approximately 4,000m3 (1,060,000 gallons) of a crude oil (Cusiana − 41°API). The spilled oil spread over part of the refinery area, affecting the wetlands that are crossed by the Arroio Saldanha creek before discharging into the Barigui River, which is a tributary of Iguassu River. This entire area crossed by the creek is referred to as Point Zero (PO). This paper presents the chemical data of 2 monitoring programs: the Barigui, Iguassu and Arroio Saldanha Rivers, and the groundwater of Point Zero. The programs were carried out in 2 phases: for 3 months immediately after the spill and 1 year later. They included the analyses of BTEX, TPH, PAH, n-alkanes, UCM and biomarkers for the water and sediment samples. The rivers program encompassed 13 stations along Barigui and Iguassu Rivers and 1 station at Arroio Saldanha Creek. The results in water and sediments demonstrated the efficiency of the recovering of the spilled oil from the water. That suggested that the impact of the spill on the Barigui and Iguassu Rivers was of a short duration after the spill. On the other hand, the hydrocarbon concentration data for Arroio Saldanha Creek during the 3 months after the spill revealed high levels of hydrocarbon contamination, which corroborated the visual inspection. The groundwater monitoring program in the terrestrial area of Point Zero was initiated shortly after the spill. The groundwater program included about 80 monitoring wells (piezometers) installed, along the Arroio Saldanha Creek and in the wetlands crossed by the creek. It could be observed that BTEX and TPH groundwater concentrations decreased significantly after one year.