BLG 4/18
ANNEX 6
Page2
(ii) To verify the effectiveness of the stripping and drainage arrangements, a measurement shall be made of the amount of oil floating on top of the departure ballast. The ratio of the volume of oil on top of the total departure ballast water to the volume of tanks that contain this water shall not exceed 0.00085. This test shall be carried out after crude oil washing and stripping in a tank similar in all relevant respects to the tank examined in accordance with (a) above, which has not been subjected to a water rinse or to the intervening water flushing permissible in (a) above.
(iii) To verify the design, installation and operation of the system, the arrival ballast, after a typical ballast voyage before which the arrival ballast tanks have been crude oil washed and during which the tanks have been water rinsed in accordance with the programme set out in the Operations and Equipment Manual, shall be totally discharged to the loading port harbour through an Oil Discharged Monitoring and Control (ODM) system approved by the Administration. The oil content of the effluent in this test shall not exceed 15 ppm. Alternatively, the option of taking ballast water samples to be analysed in a shore-based laboratory is also acceptable.
(c) During all COW system surveys, internal visual inspections of the tanks by inspectors should not be considered a mandatory requirement. When an Administration considers that there is a possible failure of the COW system indicated by other COW survey requirements, the Administration may require an internal examination of the tanks involved. Internal examinations may be completed using alternative methods, e.g., video survey or other new technology, as accepted by the Administration. "
