Environmental Assessment for Rehabilitation Plans

Acting:
Characterization of physical and biological components

Location:
Perú

Customer:
Confidential

Métodos
Caracterización en campo y análisis de laboratorio

Products
Crude oil (29.1° API)

Background information

The accidental spill of some 10,000 barrels of Buzios crude oil during the unloading operations of a tanker reached approximately 11,000 ha at sea and 120 ha on land, along a coastal marine ecosystem. This environmental emergency was attended to including source control, containment, surface recovery, cleanup of the affected area and final disposal of the contaminant and waste generated.

This environmental emergency was addressed including source control, containment, surface remediation, cleanup of the affected area and final disposal of the contaminant and waste generated.

Objective and limitations

Environmental characterization of the physical and biological components of the area reached by the spill in the intertidal and subtidal areas, in contrasting seasons (warm and cold).

Among the most relevant limitations were the long time required to obtain permits for field work, the difficulties in accessing some coastal formations, and the occurrence of abnormal swells that led to the temporary suspension of some work.

Scope of the detailed characterization

Environmental characterization of the physical component, in the seawater and sediment matrices, in the intertidal and subtidal zones, as well as the biological component, including flora, marine and terrestrial fauna and hydrobiology and biological tissue, in the coastal and marine zones, for the coastal formations and sectors affected by the spill. These same vectors were analyzed in the control (reference) sites.

Stages:

  1. Elaboration of the Sampling Plan for the characterization of physical, biological and hydrobiological components and biological tissue.
  2. Management of permits for the characterization of the physical and biological component, and entry to private coastal areas and NPAs.
  3. Field characterization work during two seasons.
  4. Laboratory analysis for the determination of concentrations of contaminants of interest in the physical component and in biological tissue samples.
  5. Characterization of the biological and hydrobiological component under ecological indicators, such as richness and abundance.
  6. Analysis and interpretation of the information generated during the environmental characterization.

Characterization effort and results

Intertidal physical component stations (seasonal)

≈ 2 500

Seasonal subtidal physical component stations (per season)

≈ 1 000

Samples for the physical component (per season)

> 12 000

Biological stations (seasonal)

≈ 100

Hydrobiological stations (per season)

≈ 900

Biological tissue samples (all seasons)

≈ 6000

Percentage of samples exceeding reference levels (all matrices, including biological tissue)

<5%