Section 10.6 Dealing with Cargo Residues and Hold Emptying Certificates

Once the main discharge of a bulk cargo is completed, the operation is not entirely over. Invariably, some amount of cargo material, known as “residues,” will remain in the holds. The thoroughness of the discharge, the nature of these residues, their proper removal or disposal, and the associated documentation are all critical final steps. These actions have implications for environmental compliance (MARPOL Annex V), the vessel’s readiness for its next employment, and sometimes for port clearance. The Master and Chief Officer must ensure that cargo residues are managed responsibly and that any required certifications regarding the state of the holds are accurately obtained or issued.

1. Definition and Nature of Cargo Residues:

Definition (MARPOL Annex V): “Cargo residues means 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.”

Nature of Residues: The amount and type of residue can vary significantly depending on:

Cargo Type:

Free-flowing granular/pelletized cargoes (e.g., some grains, pellets) tend to leave less residue than fine powders or sticky/cohesive materials.

Powdery cargoes (e.g., cement, alumina) will leave a layer of dust on all surfaces.

Sticky or caked cargoes (e.g., some concentrates, sugar if it has become damp, fertilizers that have caked) can leave significant adherent residues.

Dense cargoes (e.g., iron ore fines) can leave compacted layers on the tank top or in corners.

Thoroughness of Discharge by Stevedores: The diligence of grab operators or the effectiveness of continuous ship unloaders (CSUs) and any final clean-up equipment (e.g., bobcats, vacuum systems used by the terminal) greatly impacts the quantity of residue.

Hold Structure: Holds with many frames, brackets, and recesses (typical of older single-hull designs) will trap more residues than smooth-sided double-hull vessels.

Condition of Hold Coatings: Rough, corroded, or damaged coatings can cause cargo to adhere more readily.

2. Importance of Minimizing and Properly Managing Residues:

Preparation for Next Cargo: Excessive residues from the previous cargo can contaminate the next cargo or require extensive and costly cleaning by the ship’s crew. The less residue left by stevedores, the easier the ship’s subsequent cleaning task.

Accurate Lightship Weight: Significant unremoved residues add to the vessel’s apparent lightship weight, which can affect future cargo calculations and stability assessments if not accounted for (though this is usually a minor effect unless residues are very substantial and dense over many voyages).

Environmental Compliance (MARPOL Annex V): This is a primary driver. The disposal of cargo residues is strictly regulated to prevent marine pollution.

Safety: Some cargo residues can continue to pose hazards (e.g., dust from cement or sulphur, self-heating potential from coal fines, oxygen depletion from ore fines).

Port Regulations: Some ports or terminals may have local rules regarding the maximum amount of residue that can be left in holds or specific requirements for declaring holds empty.

3. Methods for Removing Final Residues (Post-Main Discharge):

After the main discharge equipment (grabs, CSUs) has removed as much cargo as practicable, further efforts are often needed to minimize remaining residues.

A. Stevedore-Performed Clean-up (Often Contractual):

Bobcats/Small Loaders: Stevedores often use small bulldozers or skid-steer loaders inside the holds to push remaining cargo from the wings, corners, and bulkheads towards the center of the hatch square where grabs can access it. This is common for many bulk cargoes. The Master/Chief Officer must supervise this to prevent damage to the ship (see Section 10.4).

Manual Sweeping/Shoveling by Stevedores: For some trades or by contractual agreement, stevedores may perform a final sweep or shovel clean of the tank tops.

Vacuum Systems (Terminal Provided): Some advanced terminals may use powerful vacuum systems for final clean-up of dusty or high-value cargoes.

B. Ship’s Crew Efforts (If Stevedore Clean-up is Insufficient or Not Provided):

If the holds are not left sufficiently clean by the stevedores for the vessel’s next requirements (e.g., if preparing for a different, sensitive cargo, or if residues pose a hazard), the ship’s crew may need to undertake further cleaning. This would typically involve manual sweeping, scraping, and collection of residues. This is essentially the start of the hold cleaning process for the next voyage (covered in Chapter 5).

4. MARPOL Annex V Regulations for Disposal of Cargo Residues:

This is a critical aspect and reiterates points from Chapter 5, but with a focus on the end of the discharge operation.

Classification of Residues (HME or non-HME): The first step is to know if the cargo residues are Harmful to the Marine Environment (HME). This is determined by the cargo’s classification under MARPOL Annex V (often indicated in the IMSBC Code or by the shipper).

Discharge Restrictions:

Residues Classified as HME:

Discharge into the sea is PROHIBITED worldwide.

These residues must be delivered to adequate Port Reception Facilities (PRFs).

Residues NOT Classified as HME:

Outside Special Areas: May be discharged into the sea provided the ship is en route and as far as practicable from the nearest land, but not less than 12 nautical miles.

Inside Special Areas: Discharge is generally PROHIBITED. There is a very narrow exception for unrecoverable residues if both departure and arrival ports are in the Special Area, the ship doesn’t leave it, and no adequate PRFs are available (this is hard to justify and should be a last resort, always after consulting the company).

“Unrecoverable” Residues: MARPOL Annex V acknowledges that it may not be possible to remove every last particle of cargo. The discharge provisions often apply to residues that “cannot be recovered using commonly available methods for unloading.” However, this does not permit negligent or incomplete discharge by stevedores to be simply washed overboard if those residues could have been reasonably removed by standard terminal equipment (e.g., bobcats, good grab work).

Cargo Hold Wash Water Containing Residues: As per MARPOL Annex V, cargo residues entrained in wash water are still considered “cargo residues” and are subject to the same discharge restrictions based on their HME status and location. If non-HME residues are washed out, the wash water containing them can be discharged under the same conditions as dry non-HME residues. If HME residues are washed out, the wash water containing them cannot be discharged at sea and must go to a PRF.

5. Hold Emptying Certificates / Certificates of Cleanliness (Post-Discharge):

After discharge and any final clean-up by stevedores, various parties may require or issue a certificate or statement regarding the condition of the holds.

A. Purpose:

Confirmation of Completion of Discharge: To certify that, to the best of visual inspection, all economically recoverable cargo has been discharged.

Record of Hold Condition: To document the state of cleanliness (or the amount/nature of residues remaining) after discharge.

Compliance with Port/Terminal Requirements: Some ports or terminals require such a certificate before allowing a vessel to sail, especially if there are concerns about residues being illegally discharged later.

Preparation for Next Cargo: If the next charterer or shipper requires evidence that holds were properly emptied of the previous cargo.

Commercial Purposes: May be used in relation to despatch/demurrage calculations if it confirms the time discharge was fully completed.

B. Who Issues/Requests Them?

Terminal Operators: May issue a “Hold Empty Certificate” or similar, often based on their foreman’s visual inspection.

Independent Surveyors: Appointed by charterers, receivers, or owners to conduct a post-discharge inspection and issue a certificate of cleanliness or emptiness. This is common if the next cargo is sensitive or if there are contractual requirements.

Ship’s Master/Chief Officer: May prepare their own statement or logbook entry detailing the condition of holds after discharge, especially if no formal external certificate is issued or if they disagree with one provided by others.

C. Content:

Vessel name, port, date.

Holds inspected.

A statement regarding the extent of discharge (e.g., “holds visually inspected and found to be empty of all pumpable/grabable cargo,” or “swept clean by stevedores,” or “minor residues of [cargo name] remaining on frames and ledges, estimated quantity X”).

Any remarks on damage found after discharge (important to distinguish from pre-existing damage).

Signatures of the issuing party and often a ship’s representative (Master/Chief Officer) acknowledging receipt or agreement.

D. Master’s Actions Regarding These Certificates:

Verify Accuracy: Before signing any such certificate issued by a third party, the Master or Chief Officer must personally inspect the holds to verify that the statement accurately reflects their condition.

Do Not Sign if Incorrect: If the certificate states holds are “clean and empty” but significant residues remain (beyond what is reasonable for that cargo and discharge method), do not sign it without amendment or issuing a Letter of Protest.

Clause as Necessary: If signing “for receipt only,” ensure this is clearly stated. If there are disagreements, add a remark like “Holds inspected by ship’s staff, significant residues of [cargo name] remain, estimated [quantity/description]. Vessel not responsible for removal of these residues as per C/P terms” (if applicable).

Retain Copies: Keep copies of all such certificates with the voyage records.

6. Practical Challenges and Considerations:

Defining “Empty” or “Clean”: This can be subjective and a source of dispute. What one party considers acceptably empty, another might deem to have excessive residues. Clear contractual definitions are helpful but not always present.

Responsibility for Final Clean-up: Charter parties should ideally specify who is responsible (and for whose account) for the final removal of residues beyond what normal stevedore discharge achieves. Often, this falls to the ship if a higher standard of cleanliness is needed for the next cargo than what the discharging stevedores provide.

Availability and Cost of Port Reception Facilities (PRFs):

Lack of adequate PRFs is a global problem. Even if a ship wants to dispose of HME residues or contaminated wash water ashore, facilities may not be available, or may be prohibitively expensive, or may involve long delays.

The Master should liaise with agents well in advance if PRF use is anticipated.

Pressure to Sail: There can be commercial pressure to sail quickly after discharge, sometimes before a truly thorough assessment of remaining residues or final clean-up can be completed to the ship’s satisfaction. Safety and environmental compliance must not be compromised.

7. Master’s Overall Responsibilities:

Ensure Discharge is as Complete as Practicable: Supervise stevedores to maximize cargo outturn and minimize residues left onboard.

Manage Residue Disposal in Accordance with MARPOL Annex V: This is a non-negotiable environmental and legal obligation. Ensure all crew are aware of and comply with these regulations.

Accurate Record-Keeping: Ensure the Garbage Record Book (Part II for cargo residues) is meticulously and accurately completed for any disposal of residues at sea or to PRFs.

Verify and Appropriately Handle Hold Emptying Certificates: Protect the owner’s interests by ensuring any such documents accurately reflect the true condition of the holds.

Liaise with All Parties: Maintain clear communication with stevedores, terminal operators, agents, and the company regarding residue removal, disposal, and certification.

Dealing with cargo residues and obtaining appropriate hold emptying certificates forms the final act of a cargo voyage. It requires the Master’s diligence in ensuring operational thoroughness, unwavering commitment to environmental protection, and careful attention to documentation to close out the voyage successfully and prepare the vessel for its next employment.