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5 Waste Management and Disposal

5.1 Health concerns Waste can contain hazardous microbial, chemical or physical agents. For example, sharp objects are in themselves dangerous. Furthermore, those objects may harbour infectious agents. Used syringes are a good example and can transmit disease causing agents such as hepatitis C virus and human immunodeficiency virus. Medical waste requires special management (WHO internet site). Furthermore, harmful chemicals can be deposited in waste. Unsafe management and disposal of ship wastes can readily lead to adverse health consequences. Humans can become exposed directly, both on ship and at port, due to contact with waste that is not being managed in a safe manner. Exposure can also occur via the environmental transfer of disease-causing organisms or harmful substances due to unsafe disposal. However, waste can be managed and disposed of in ways that prevent harm occurring. Risks of harm arising due to improperly managed ship waste are increasing with the increasing number of ships in service and the increase in shoreline habitation. Waste streams on ships include sewage, grey water, (discard water from deck drains, showers, dishwashers and laundries) garbage, ballast water, effluent from oil/water separators, cooling water, boiler and steam generator blow down, medical wastes, industrial waste water (e.g. from photo processing) and hazardous waste. Food wastes and refuse readily attract disease vectors (see Chapter 8) including rodents, flies and cockroaches. Details concerning the proper retention, selective collection, storage and disposal of such wastes on board, on shore, and overboard (where shore areas will not be affected) is described by MARPOL Annex V and includes measures to prevent the creation of health hazards.

5.2 Relevant Aspects of the International Health Regulation Waste management from ships is covered in the IHR and is covered in more detail in MARPOL.

5.3 International Convention for the Prevention of Pollution from Ships

The International Convention for the Prevention of Pollution from Ships (MARPOL 73/78) was adopted by the International Conference on Marine Pollution in 1973 and has been subject to numerous amendments as it is updated including the 1978 Protocol and amendments collated into a consolidated version in 2002. Regulations covering the various sources of ship-generated pollution are contained in the six Annexes of the Convention:

Annex I. Regulations for the Prevention of Pollution by Oil. Annex II. Regulations for the Control of Pollution by Noxious Liquid Substances in

Bulk.

Annex III. Prevention of Pollution by Harmful Substances Carried by Sea in Packaged Form.

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Annex IV. Prevention of Pollution by Sewage from Ships (entry into force date 27 September 2003).

Annex V. Prevention of Pollution by Garbage from Ships. Annex VI. Prevention of Air Pollution from Ships (adopted September 1997 - not yet in

force)

5.4 Risk factors and control measures for ship waste

5.4.1 Liquid wastes Drain, soil and waste pipes should be of adequate size, and be maintained frequently to prevent clogging and the backflow of sewage and bath water or contaminated wastes into the fixtures and spaces served by the collection system. Sewage, food particles, putrescible matter and toxic substances should not be discharged to the bilge. Sewage, ballast water, bilge water or any other liquid containing contaminating or toxic wastes should not be discharged within an area from which water for a water supply is drawn, or in any area restricted for the discharge of wastes by any national or local authority.

5.4.2 Overboard discharge of waste Barges and/or trucks for the reception of liquid wastes, or shore connections at ports to receive these wastes into a sewer system, should be provided at ports. Where the ports servicing area or barge does not provide hose or connections to receive liquid wastes, the ship should provide a special hose and connections large enough to allow rapid discharge of the wastes. This hose should be durable, impervious, and with a smooth interior surface. It should be of a fitting different from that of the potable water hose or other water filling hose, and it should be labelled FOR WASTE DISCHARGE ONLY. After use, the hose should be cleaned, disinfected and stored in a convenient place, labelled WASTE DISCHARGE HOSE. It is forbidden to dispose of liquid waste around port areas, in compliance with the exceptions set forth on Rule 9 of MARPOL Annex IV.

5.4.3 Wastes requiring treatment All ships should be equipped with facilities for managing wastes from toilets and urinals, faecal material from hospital facilities and medical care areas, and wastes from food-refuse grinders. These facilities should include either treatment facilities and/or safe holding tanks, properly equipped with pumps and piping. Wastes from safe holding tanks may be discharged to connections in the ports or to special barges or trucks for the reception of these wastes. The design of treatment facilities and waste holding tanks should be based on 114 litres per capita per day of liquid waste. Connections should comply with Rule 11 of MARPOL Annex IV, as for theirs external and internal diameters, centre to centre diameters, and other aspects in the rule.

5.4.4 Galley wastes All galley wastes that may contain grease should flow through grease traps to a retaining box prior to discharge overboard with a distance of 3 N.M. from the closets line of land (territorial sea 12 N.M.) or to a treatment aboard ship. The grease collected may be disposed of by incineration, by storage for shore disposal, or by overboard discharge on the high seas.

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5.4.5 Excess sludge Excess sludge should be stored for appropriate disposal to land based facilities or when on the high seas.

5.4.6 Food wastes All ships should be equipped with facilities for safe storage of food refuse. All food refuse should be received and stored in watertight, non-absorbent and easily cleaned containers, fitted with tight covers which should be closed during food preparation, food serving and cleansing operations in food-handling spaces. These containers should be placed in waste storage spaces, specifically constructed and used for this purpose, or on open decks when necessary. After each emptying, each container should be thoroughly scrubbed, washed, and treated with disinfectant, if necessary, to prevent odours and nuisances and to minimize attraction of rodents and vermin.

5.4.7 Water supply for food-refuse grinders Approved back-flow preventers (vacuum breakers) or acceptable air-gaps should be installed in the water supply lines to the grinders.

5.4.8 Dry refuse Dry refuse should be stored in tightly covered bins, or in closed compartments, protected against the weather and the entry of rodents and vermin. The containers should be thoroughly cleaned after emptying to discourage harbourage of rodents and vermin.

5.4.9 Health care wastes All ships should be equipped with facilities for treating and/or safely storing medical care wastes. Medical waste is any waste generated during patient diagnosis, treatment or immunization. Medical waste is of two categories: infectious and non-infectious. Infectious medical waste is liquid or solid waste that contains pathogens in sufficient numbers and with sufficient virulence to cause infectious disease in susceptible hosts exposed to the waste. Non-infectious medical waste includes disposable medical supplies and materials that do not fall into the category of infectious medical waste.

Infectious waste should be safely stored or sterilized, e.g. by steam, and suitably packaged for ultimate disposal ashore. Medical waste should be labelled. Ships properly equipped may incinerate paper and cloth based medical waste but not plastic and wet materials. Sharps should be collected in plastic autoclavable sharps containers and retained on board for ultimate disposal ashore. Unused sharps should be disposed of ashore in the same manner as medical waste.

Liquid medical wastes may be disposed of by discharging them into the sanitary system. Non-infectious medical waste may be disposed of as garbage, not requiring steam sterilizing or special handling.

5.5 References MARPOL 73/78. International Convention for the Prevention of Pollution from Ships, 1973, as modified by the Protocol of 1978 relating thereto (MARPOL 73/78) as amended. Reference

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from: http://www.imo.org/home.asp

WHO internet site. Details of health care waste management can be found via the WHO internet site http://www.healthcarewaste.org/