Improvement jetties near petroEcuador in La Liberdad, Ecuador

Abstract

The first issue involves the accessibility of the pier of the refinery where coastal tankers moor to load or unload their cargo. The current depth at the pier is too small for large coastal tankers to fully load when mooring at the pier. In order to increase their cargo capacity, the depth in the mooring area should be increased. To expand the present pier into deeper water would be too expensive. Another option is dredging. The stability of the pier, dolphins and gantry might be endangered by dredging activities, but since only 2 to 3 meters of soil need to be dredged, and because the gantry has a reach of 10 m., it is possible to design the dredging area far enough from the pier to not have an effect on the pier- and gantry stability. The dolphins are closer to the dredging area and need to be replaced. The new dolphin design is adjusted to the dredging depth. The new mooring area is only accessible for the largest mooring coastal tankers when fully loaded during several hours a day, because of the tides. Therefore they might have to wait in the mooring area for several hours if the pier is occupied. Smaller or unloaded tankers can reach the mooring area at any time. The second issue is about oil leakage from the refinery into the surrounding soil. On the area of the refinery of La Libertad petrochemical substances have been leaking into the subsoil. This has lead to the contamination of the soil around the refinery of La Libertad. Most of the pollution is found on the area of the refinery itself. However, on the ocean side of the refinery the contamination reaches out of the refinery's territory. A gasoline smell can be detected and petrochemical substances have been found in the subsoil of the beach. In this area there is a primary school, a military campus and a little village called La Carioca, that all suffer from this contamination. The source of the contamination of the beach area was a leaking pipe, upstream of the beach. This pipe has been traced and has been replaced by a new pipe. The contamination of the soil in this area causes risks for the human health and for the environment. To reduce the impact of the pollution in the contaminated area on the ocean side of the refinery of La Libertad different alternatives have been generated. Only methods have been used that involve groundwater or groundwater flow. The best way to reduce the impact of the contamination is to construct a slurry wall between the ocean and the contaminated plume. On the downstream side of the contaminated groundwater plume three extraction wells are located. The plume is entirely captured in the combined capture zone of these wells so the contamination can not spread any further. On the upstream side of the contaminated groundwater plume an injection well is located. This injection well makes sure that the plume can be removed more quickly. Additives can be put in the water that is injected through the injection well. This will cause more components of the oil mixture to dissolve in the water so more of the pollution can be removed from the soil.