Mandatory pre-wash MARPOL Annex II

Chemical tankers which have discharged cargoes that presents a major hazard to the marine environment (category X substances) are required to carry out a mandatory prewash before leaving the port. The tank washings, resulting from the prewash, need to be discharged to a shore reception facility. This prewash shall be witnessed by an ILT inspector, except for the Port of Rotterdam area. In that area, the prewash shall be witnessed by the inspectors of the Port of Rotterdam Authority.

If the prewash is carried out in accordance with the MARPOL requirements the Cargo Record Book will be endorsed by the ILT inspector. In the Port of Rotterdam this will be done by an inspector of the Port Authorities.

Witnessing the mandatory prewash by an ILT inspector is a legal obligation. In certain cases an exemption from the mandatory prewash, in line with the Marpol Annex II requirements, is possible. If the mandatory prewash is not carried out in accordance with the requirements, or not carried out when required, legal steps will be taken.

Requesting prewash attendance by the ILT

If vessels intending to discharge MARPOL Annex II category X cargo are expected in the Netherlands they must notify the ILT (Port State Control) 24 hours in advance (via the shipping agent, if need be). In the port of Rotterdam area , this information must be send directly to the Port of Rotterdam Authority. The ILT must take into account the daily planning of the inspectors.

In addition, the shipping agent must provide the ILT with a notice by telephone 3 hours in advance. This additional notice can be communicated by the shipping agent both during and outside office hours, via the ILT Reporting and Information Centre. They can be reached by calling +31 (0)88 4890000.

To arrange the pre-wash as efficiently as possible for all parties, the ship and the agent must take care of the following:

  • The tanks which are required to be prewashed need to be discharged and stripped according to the approved Procedures and Arrangement manual of the chemical tanker.
  • The slob barge or truck that will receive the tank washings resulting from the prewash needs to be present at the chemical tanker.
  • The pre-wash may only start when the ILT inspector gives the go-ahead. However, for efficiency reasons, everything must be ready for the pre-wash when the ILT inspector comes on board. If not everything is ready, the ILT inspector can decide to disembark to perform other duties.
  • If the ILT inspector needs additional transport to reach the ship, like a  boat, the costs thereof are payable by the ship. In the case of chemical tankers that cannot be reached from shore, shipping agents must ensure that the ILT inspector can board via the gangway. The shipping agent is responsible for ordering the  boat. A crew of two persons is required on the boat when navigating in dark hours. This is to ensure the safety of the ILT inspector.

New requirements for Cargo residues and tank washings of persistent floating products (like Paraffin Wax)

IMO adopted resolution MEPC.315(74), amending regulations 1, 13, appendix IV and appendix VI of MARPOL Annex II concerning cargo residues and tank washings of persistent floating products with a high viscosity and/or high melting point in specific areas. The amendments enter into force on 1st January 2021. These amendments have newly defined persistent floating products ("persistent floater(s)") and impose stricter prewash requirements.

A prewash procedure shall be applied in certain areas (e.g. North West European waters) for substances that are persistent floaters with a viscosity equal to or greater than 50 mPa.s at 20°C and/or with a melting point ≥0°C. These substances are identified by '16.2.7' in column 'o' of Chapter 17 of the amended IBC Code (2020 Edition). The following shall apply:

  • a prewash procedure as specified in appendix 6 to this annex shall be applied;
  • the residue/water mixture generated during the prewash shall be discharged to a reception facility at the port of unloading until the tank is empty; and
  • any water subsequently introduced into the tank may be discharged into the sea in accordance with the discharge standards in regulation 13.2.”

In addition, the new amendments also impact the standard format of the Procedures and Arrangements (P&A) Manual (Appendix IV of MARPOL Annex II). Therefore, P&A Manuals on board all ships shall be amended, as shown in MEPC.315(74), before 1 January 2021.

For MARPOL Annex II category X Paraffin Wax cargoes the washing may only be started after the ILT inspector is on board. For category Y this may be started, after consulting with the ILT inspector, before he is on board.