425 - 08/05 - Implications of Cargo Residues as Garbage

The amendments to the Appendix to Annex V of Marpol as approved at MEPC49 (14 to 18 July 2003) and adopted at MEPC51 (29 March to 2 April 2004) came into force on 1 August 2005 and includes the addition of cargo residues as garbage.

Thus cargo residues that remain after discharge fall under the definition of garbage as operational waste requiring it to be disposed of outside Special Areas and then, as far away from the "nearest land" in accordance with Reg. 3 (essentially the criteria being whether the garbage floats minimum 25 miles and if it sinks minimum 12 miles). Disposal of garbage is prohibited within Special Areas as per Reg.5, other than food waste when a minimum of 12 miles from the "nearest land". Previously the International Chamber of Shipping (ICS) did not hold the view that Annex V covers cargo residues but that such residues should not be discharged without due consideration of their effect on the marine environment. Clarification appears to have been made by the International Maritime Organization (IMO) in that the Garbage Record Book is to include entries for disposal of cargo residues. With this clarification it would appear that cargo residues can only be disposed of and/or discharged overboard when the vessel is at the aforementioned distances from the nearest land and then only outside of a Special Area.

If the cargo is toxic to the marine environment and its watercourses and/or considered as noxious then the UK has additional strict pollution regulations pertaining to the disposal of and/or discharge of cargo residues in its national waters and by vessels flying its flag. Individual Flag and Coastal States may have their own requirements that may incorporate such instruments as MARPOL 73/78 and/or the London Dumping Convention 1972.

MARPOL ANNEX I – Regulations for the Prevention of Pollution by Oil

Annex V Reg. 1(1) of the Marpol Convention outlines if the substance is defined or listed in other Annexes then Annex V does not apply, the other particular Annex applies. In the case of a cargo that has a hydrocarbon (petroleum) oil content such as a Petroleum Coke, where the effluent that is generated contains "oil" then it would appear such product and any effluent derived from a hold cleaning process can only be discharged overboard in compliance with Annex I.

Annex I Reg. 1(1) defines Oil

“petroleum in any form including crude oil, fuel oil, sludge, oil refuse and refined products…”.

Annex I Reg. 1(2) defines Oily Mixture

“a mixture with any oil content”.

Annex I Reg. 2(1) provides

“Unless expressly provided otherwise, the provisions of this annex shall apply to all ships”


Accordingly, Annex I applies to all ships both oil tankers and dry cargo vessels.

Annex I Reg. 9(1)

“Control of Discharge of Oil” sets out that “any discharge into the sea of oil or oily mixtures from ships to which this Annex applies shall be prohibited except when the following conditions are satisfied:a).  For an oil tanker … … … (not applicable)b).  From a ship of 400 tons gross tonnage and above other than an oil tanker and from machinery space bilges excluding cargo pump-room bilges of an oil tanker unless mixed with cargo residue:  I.  the ship is not within a special area (see Annex I Reg. 10);  II.  the ship is proceeding en route;  III.  the oil content of the effluent without dilution does not exceed 15ppm; and  IV.  the ship has in operation equipment as required by Reg 16 of this Annex”.

Essentially Annex I Reg.16 requires vessels of 400 tons gross tonnage and above to be fitted with oil filtering equipment

“as will ensure that any oily mixture discharged into the sea after passing through the system has an oil content not exceeding 15ppm”.

It could be said that Annex I applies to only oil residues generated in the machinery spaces of ships other than oil tankers given that there is a reference to only machinery spaces in Annex I Reg. 9(b), i.e. there are oily cargo residues and oily machinery space residues in oil tankers and only oily machinery spaces residues in vessels other than oil tankers. However, it is submitted that such a narrow interpretation may not be correct. An analogy would be if ballast water in a cargo hold of a bulk carrier became contaminated with fuel oil from an adjacent bunker tank through a breached bulkhead or breached hold floor then Annex I would be applicable. Thus the effluent generated from a hold washing operation of a cargo that has a hydrocarbon/petroleum

“oil content”

must, out of necessity, make it an

“oily mixture”

and handled in accordance with Annex I. Annex I would appear to be quite clear in that it applies to all ships, it applies to Petroleum



‘Oily Mixtures’

as defined therein and that discharge of


is prohibited except when certain conditions are satisfied.


Such material can be pollutants in themselves. If the detergent/chemical used is a substance that falls within Annex I (Oil) or Annex II (Noxious Liquid Substance) then the washing effluent generated from any washing process using the particular substance may require to be handled in accordance with the particular Annex. The associated restrictions as to its disposal overboard can therefore apply.

Source of information:

Minton, Treharne & Davies Ltd.

Cardiff, UK



Staff Author