Section 5.4 Disposal of Cargo Residues and Wash Water (MARPOL Annex V)

The process of cleaning cargo holds on a bulk carrier inevitably generates waste: cargo residues swept, scraped, or washed out, and wash water, which may or may not contain cleaning agents. The disposal of this waste is not a matter of convenience but is strictly governed by international regulations, primarily MARPOL Annex V (Regulations for the Prevention of Pollution by Garbage from Ships). As a Master Mariner, ensuring full compliance with these environmental regulations is a non-negotiable responsibility. Improper disposal can lead to severe penalties, damage to the marine environment, and harm to the vessel’s and company’s reputation. This section will detail the MARPOL Annex V requirements pertinent to cargo residues and hold wash water, emphasizing the operational procedures and record-keeping necessary for compliance.

1. MARPOL Annex V – The Regulatory Framework:

MARPOL Annex V aims to prevent pollution of the sea by garbage from ships. “Garbage” under this Annex is broadly defined and includes all kinds of food wastes, domestic wastes, and operational wastes, the latter category being most relevant here as it includes cargo residues and cleaning agents/additives contained in hold wash water.

Key Principles of MARPOL Annex V:

Prohibition of Discharge (General Rule): The general principle is that the discharge of all garbage into the sea is prohibited, except as expressly provided otherwise in the regulations.

Special Areas: Stricter discharge requirements apply within designated “Special Areas” (e.g., the Mediterranean Sea, Baltic Sea, Black Sea, Red Sea, “Gulfs” area, North Sea, Antarctic area, and Wider Caribbean Region). In many Special Areas, the discharge of most types of garbage, including many cargo residues, is completely prohibited.

Harmful to the Marine Environment (HME): Cargo residues classified as HME are subject to more stringent discharge restrictions. The shipper is responsible for declaring if a cargo is HME based on criteria set out by the IMO.

Port Reception Facilities: Flag States and port States are obliged to ensure the provision of adequate port reception facilities for ship-generated garbage, including cargo residues.

Garbage Management Plan: Ships of 100 gross tonnage and above, and every ship certified to carry 15 or more persons, must carry a Garbage Management Plan. This plan provides written procedures for collecting, storing, processing, and disposing of garbage, including the use of equipment onboard.

Garbage Record Book: Ships of 400 gross tonnage and above, and every ship certified to carry 15 or more persons engaged in voyages to ports or offshore terminals under the jurisdiction of another Party to the Convention, must maintain a Garbage Record Book (GRB). All discharges to sea, to reception facilities, or incineration must be recorded.

2. Definitions Relevant to Hold Cleaning Waste:

Cargo Residues: Defined in MARPOL Annex V as “the remnants of any cargo material on board in cargo holds or tanks which remain after loading and unloading procedures are completed, including loading and unloading excesses and spillage, whether in wet or dry condition or entrained in wash water, excluding cargo dust remaining on deck after sweeping or dust on the external surfaces of the ship.”

Important Note: This definition means that even residues entrained in wash water are still considered “cargo residues” and are subject to the discharge provisions for cargo residues, not just “wash water.”

Cleaning Agents or Additives: Substances used for cleaning purposes. If contained in hold wash water, their discharge is subject to specific conditions.

Harmful to the Marine Environment (HME): Solid bulk cargoes possessing properties that, when discharged into the marine environment, could cause harm through physical, chemical, or biological effects (e.g., persistence, toxicity, bioaccumulation, interference with other legitimate uses of the sea). The IMSBC Code (Appendix I) indicates which listed solid bulk cargoes are classified as HME. For unlisted cargoes, the shipper must declare HME status based on IMO criteria.

3. Discharge Provisions for Cargo Residues (MARPOL Annex V, Regulation 4 & 6):

The rules for discharging cargo residues depend on whether the vessel is inside or outside a Special Area and whether the residues are classified as HME.

A. Discharge of Cargo Residues OUTSIDE Special Areas:

Cargo Residues NOT Classified as HME:

May be discharged into the sea provided that:

The ship is en route.

The discharge is made as far as practicable from the nearest land, but in any case not less than 12 nautical miles from the nearest land.

For cargo residues that cannot be recovered using commonly available methods for unloading, specific discharge requirements related to the ship’s speed and discharge rate may apply to ensure they are not discharged in excessive concentrations in a limited area.

The ship has an approved Garbage Management Plan and maintains a Garbage Record Book.

Cargo Residues Classified as HME:

Discharge is PROHIBITED. These residues must be discharged to port reception facilities.

B. Discharge of Cargo Residues INSIDE Special Areas:

General Rule: Discharge of ALL cargo residues is PROHIBITED.

Exception (Very Limited): For cargo residues that cannot be recovered using commonly available methods for unloading (i.e., minor, unrecoverable quantities):

The discharge is only permitted if:

The ship is en route.

Both the port of departure and the next port of destination are within the Special Area, and the ship will not transit outside the Special Area between these ports.

No adequate reception facilities are available at those ports (this is a very strict condition and often difficult to prove or rely upon).

The discharge is made as far as practicable from the nearest land, but in any case not less than 12 nautical miles from the nearest land.

The residues are NOT classified as HME.

This exception is very narrow and should be approached with extreme caution. The primary expectation is that residues generated within Special Areas will be discharged ashore.

“En Route” Requirement: This means the vessel must be proceeding by sea on a voyage between ports. Discharges while stationary (e.g., at anchor waiting for orders) are generally not permitted.

“Nearest Land”: The definition of “nearest land” is provided in MARPOL and can be complex, sometimes referring to baselines from which territorial seas are measured, not just the visible coastline. Navigating officers must be precise.

4. Discharge Provisions for Hold Wash Water Containing Cleaning Agents or Additives (MARPOL Annex V, Regulation 4):

General Principle: Cleaning agents or additives contained in cargo hold wash water may be discharged into the sea, provided that:

They are NOT classified as HME.

The discharge occurs OUTSIDE Special Areas.

The ship is en route.

The discharge is made as far as practicable from the nearest land, but in any case not less than 12 nautical miles from the nearest land.

HME Cleaning Agents: If the cleaning agent or additive itself is classified as HME, its discharge into the sea is PROHIBITED everywhere.

Inside Special Areas: Discharge of wash water containing cleaning agents or additives is PROHIBITED within Special Areas.

IMO Evaluation: The IMO has established procedures (Guidelines for the Implementation of MARPOL Annex V, MEPC.295(71) and earlier versions) for evaluating cleaning agents. Products that have been evaluated and found not to cause harm to the marine environment when used for cleaning cargo holds and external surfaces may be discharged under the conditions above. The Master should ensure that any chemicals used for hold cleaning, if their washings are intended for discharge at sea, are accompanied by documentation confirming they are not HME and are suitable for discharge under MARPOL. If in doubt, or if such documentation is unavailable, the wash water should be treated as if it contains HME substances and retained for discharge to a port reception facility.

5. Practical Implications and Best Practices:

Minimize Residue Generation: Good unloading practices (e.g., thorough grab work, use of bobcats if permissible) can minimize the amount of residue left in holds, reducing the cleaning effort and the volume of waste to be managed.

Dry Cleaning First: Maximize dry cleaning (sweeping, scraping) to remove as much residue as possible before washing. This significantly reduces the amount of residue entrained in wash water.

Water Conservation during Washing: Use water efficiently during washing to minimize the volume of wash water generated, especially if it needs to be retained onboard or if freshwater is used.

Segregation of Wash Water: If some holds are washed with chemicals and others only with water, keep the wash waters segregated if possible, especially if the chemically treated water cannot be discharged at sea.

Plan for Port Reception Facilities:

Before arrival at a port where hold cleaning and discharge of residues/wash water to shore is anticipated, the Master should, through the agent, inquire about the availability, capacity, procedures, and cost of port reception facilities.

Provide advance notification to the port of the types and estimated quantities of garbage to be discharged.

Avoidance of Special Areas for Discharge: Plan voyages and cleaning schedules, where feasible, to allow for permissible discharges to occur well outside of Special Areas.

Crew Training: Ensure all crew members involved in hold cleaning and waste management are familiar with MARPOL Annex V requirements, the ship’s Garbage Management Plan, and the correct procedures for handling and disposing of cargo residues and wash water.

6. The Garbage Record Book (GRB):

This is a critical legal document for demonstrating compliance with MARPOL Annex V.

Entries Required:

Part I (for all garbage): Records discharges of operational wastes (including cargo residues not entrained in wash water if handled dry), food wastes, domestic wastes, etc., to sea or to port reception facilities, as well as incineration.

Part II (for cargo residues, as per MEPC.277(70) for ships carrying solid bulk cargoes): Specifically records the discharge of cargo residues.

Each discharge or completed incineration must be recorded and signed by the officer in charge and by the Master.

Entries must include:

Date and time of discharge/incineration.

Position of the ship (latitude and longitude) at the time of discharge, or name of port if discharged ashore.

Category of garbage discharged (e.g., “Cargo Residues (non-HME),” “Cargo Residues (HME)”).

Estimated amount discharged (in m³ or other units).

For discharges to sea, confirmation that the ship was en route and the relevant distance from nearest land/Special Area requirements were met.

For discharges to port reception facilities, the name of the port and a receipt or certificate from the facility should be obtained and kept with the GRB.

Accuracy and Integrity: The GRB is subject to close scrutiny by PSC. Entries must be accurate, timely, and truthful. Falsification is a serious offense with severe penalties.

Retention: The GRB must be kept onboard for at least two years from the date of the last entry.

Analysis for the Master (Disposal of Residues and Wash Water): The Master’s responsibilities in this area are heavily weighted towards environmental stewardship and regulatory compliance.

Ultimate Responsibility for Compliance: Ensure all operations related to the disposal of cargo residues and hold wash water strictly adhere to MARPOL Annex V and the ship’s Garbage Management Plan.

Verification of HME Status: Confirm the HME status of all cargoes carried. If a shipper fails to declare this, or if there is doubt, the cargo should be treated as HME by default for disposal purposes until confirmed otherwise.

Decision-Making for Discharge: The Master makes the final decision on whether a discharge to sea is permissible, based on the vessel’s position, the nature of the waste, and the prevailing regulations. This requires careful navigation and awareness of Special Area boundaries.

Supervision of Record-Keeping: Ensure the Garbage Record Book is meticulously and accurately maintained by the designated officer (usually the Chief Officer). Review and sign entries regularly.

Liaison for Port Reception: Proactively manage arrangements for discharge to port reception facilities when required, ensuring minimal delay to the vessel.

Promoting Environmental Awareness: Foster a strong environmental conscience among the crew regarding the importance of proper garbage management and pollution prevention.

Staying Updated: MARPOL regulations are subject to amendment. The Master must ensure the vessel has the latest versions of Annex V and associated guidelines, and that the crew are aware of any changes.

The responsible management and disposal of cargo residues and hold wash water are essential components of modern, environmentally conscious bulk carrier operations. Adherence to MARPOL Annex V not only protects the marine ecosystem but also safeguards the vessel and its operators from legal and financial repercussions. The Master’s leadership in this area is paramount.