MARPOL states that after discharging, all tanks must be pre-washed and the resulting residues discharged to a reception facility: –

Regulation 16

4 A tank which has carried a Category X substance shall be prewashed in accordance with regulation 13.6. The appropriate entries of these operations shall be made in the Cargo Record Book and endorsed by the surveyor referred to under paragraph 1 of this regulation.

However, there are still ports where an approved MARPOL surveyor is not available and/or no reception facilities are available, which leaves the Master with a question of what to do now.

Luckily, MARPOL provides a solution for such a position at Regulation 13: –

Regulation 13

4 Exemption for a prewash

On request of the ship’s master an exemption for a prewash may be granted by the Government of the receiving Party, where it is satisfied that:

.1           the unloaded tank is to be reloaded with the same substance or another substance compatible with the previous one and that the tank will not be washed or ballasted prior to loading; or

.2           the unloaded tank is neither washed nor ballasted at sea. The prewash in accordance with the applicable paragraph of this regulation shall be carried out at another port provided that it has been confirmed in writing that a reception facility at that port is available and is adequate for such a purpose; or

.3           the cargo residues will be removed by a ventilation procedure approved by the Administration in accordance with appendix 7 of this Annex.

However, all these solutions still require the attendance of an approved government surveyor, who should attend the vessel in accordance with his duties as laid out by MARPOL to confirm in writing the reasons why Regulation 16 cannot be complied with, and endorse the CRB accordingly.

MARPOL annex II surveyors

The International Convention for the prevention of pollution from ships (MARPOL 73/78) annex II, Regulation 16 requires the government of each party within the convention to appoint or authorise surveyors for the purposes of exercising control procedures developed by the International Maritime Organisation. The Merchant Shipping (dangerous or noxious liquid substances in bulk) Regulations 1996 (Statutory Instrument (S.I.) 1996/3010, as amended by S.I. 1998/1153) implements Annex II of MARPOL and refers to MARPOL surveyors in Regulation 9(2).

Duties of a MARPOL surveyor:

A MARPOL surveyor will only attend if required by a ship owner or his agent. The duties of a MARPOL surveyor are briefly: –

• To attend the completion of the unloading of all category X substances and verify that the pre-wash has been conducted.
• To attend where the unloading of category Y and Z substances cannot be carried out in accordance with the ship’s procedures and arrangements manual.
• To attend vessels, such as “offshore supply vessels,” and verify that cargo tanks which have contained noxious liquid substances of pollution category X, Y or Z have been cleaned and the residues and washings have been put ashore to port waste reception facilities in accordance with the procedures and arrangements manual.
• To exempt ships from the requirements of Regulation 13.4 of MARPOL ANNEX II, exemption for a “pre-wash”, as required. If the pre-wash requirements cannot be met at the discharge port, but will be carried out at the next port, it is to confirmed in writing that a reception facility at the other port is available and is adequate for such purpose.
• To endorse each ship’s Cargo NLS record book accordingly.

If NO MARPOL surveyor is available, or fails to attend then:

1/         Issue an LOP to the fact that a MARPOL Surveyor was unavailable, or did not attend as appropriate.

2/         Discharge the pre-washings as arranged, and

3/         Endorse the CRB, stating that a MARPOL surveyor was unavailable and keep records of all communications to agents, charterers and owners on this subject.

If NO MARPOL facilities are available, then:

1/         Issue an LOP to the fact that no MARPOL reception facilities were available, requesting the terminal representatives and agents to sign.

2/         Endorse the CRB, stating that no MARPOL reception facilities were available and keep records of all communications to agents, charterers and owners on this subject.

3/         At the next port, request the attendance of an approved MARPOL surveyor and arrange for the pre-washings to be discharged ashore to any available reception facilities.

In situations where those Cat X tanks are urgently required for another product, or damage to coatings may occur if that product is not cleaned, then:

As is noted by Regulation 13 part 4.2: –

.2         the unloaded tank is neither washed nor ballasted at sea.

Under this regulation, washing of these tanks is not permitted until the next port. However, this may be impractical due to a long voyage, or the residues causeing coating damage if left in the tanks for a prolonged period or some other reason requires the cleaning of those Cat X tanks.

In these situations, and bearing in mind that any pre-washings will need to be retained on-board, the following actions are recommended:

1/         Prepare a tank cleaning plan, stating:

• How the pre-wash is to be conducted, to include details of the receiving cargo tank.
• The tank cleaning procedure following the pre-wash, including details of how the washings are to be disposed.
• The anticipated date and port of disposal to shore reception facilities of the pre-washings contained in the receiving tank.
• Details of the pre-washing plan for this receiving tank to shore reception facilities.

2/         If the next port is known, request the attendance of an approved MARPOL surveyor and arrange for the pre-washings to be discharged ashore to any available reception facilities.

3/         Contact the vessels Flag State explaining the situation, including the proposed tank cleaning plan and confirmation of the details of the attending MARPOL surveyor at the next port, requesting a Letter of Authority to pre-wash those tanks to the alternative vessel’s reception tank.

4/         Endorse the CRB at parts J and K accordingly.