Construction and Accommodation Barge. Dimensions: 69X18X4.5 m, 120-ton capacity crane. This specially built barge for marine construction also provides accommodation fin fully air conditioned quarters. The 120-ton crane is a pedestal mounted American model 9760 with a clamshell attachment. Posidonia is additionally equipped with the latest electronic communications equipment, helipad for Class I, II and III helicopters and three 96 KW generators. accommodation fin fully air conditioned quarters. The 120-ton crane is a pedestal mounted American model 9760 with a clamshell attachment. Posidonia is additionally equipped with the latest electronic communications equipment, helipad for Class I, II and III helicopters and three 96 KW generators.