On the southern slopes of the 4,000 m plus Mount Cameroon, one of Africa’s largest active volcanoes, the seaside city of Limbe is famous for its black sand beaches and the annual Mount Cameroon Race of Hope. However, there is more than tourism and basalt rock. The nearby capital of Douala may be the economic heart of the country, but Limbe is undoubtedly the oil centre of Cameroon.
The majority state-owned Sonara refinery treats crude oil from Cameroon, Nigeria and Equatorial Guinea, serving te capital Douala, all coastal settlements and large parts of the country. The facilities have a capacity of 2.1 million tonnes of crude oil per year, with extensions programmes to increase capacity to 3.5 million tonnes. The ships call at Cape Limboh, which is linked by 24’’ and 30’’ pipelines to the refinery. Since October 1995 tankers of 30,000 to 90,000 tonnes berth, load and off-load petroleum products at the quay of Wharf n°2. Operations at this vital refinery ultimately depend of the receiving facilities at Cape Limboh.
The contract called for drilling and installation of five dolphin piles and repairing of the damaged jetty at the Sonara refinery.
DEME company GeoSea, a specialised company for rock socketing works and the handling, installation and grouting of supersize monopiles in a marine environment, was awarded the contract.
With the ‘Vagant’ jack-up vessel GeoSea drilled five basalt rock sockets, each one with a length of 10 m and a diameter of 2 m. As soon as a rock socket was finished, GeoSea installed and grouted in the drilled hole a dolphin pile, with a length of 51 m, a diameter of 1.85 m, and a weight of 75 tonnes. Finally, the new superstructures of the jetty were installed.