Marpol recognises persistent floaters

FLOAT ON

MARINE • AFTER MANY YEARS OF DISCUSSION, THE TREATMENT OF ‘PERSISTENT FLOATING PRODUCTS’ WILL BE INTRODUCED INTO MARPOL, BRINGING NEW OPERATIONAL CONTROLS

IN MAY 2019, the International Maritime Organisation’s (IMO) Marine Environment Protection Committee (MEPC) adopted Resolution MEPC.315(74), amending Annex II of the International Convention for the Prevention of Pollution from Ships (Marpol). Those amendments bring into Marpol Annex II new restrictions on the discharge of cargo residues and tank washings of persistent floating products, which take effect on 1 January 2021.

The amendment addresses in particular the noxious problem of waxy residues that have washed up on shores around Europe; it has been a long time in development and, in this amendment, has been restricted to European waters, with non-European states feeling there is no need for it to be applied.

What does MEPC mean by ‘persistent floater’? That is dealt with in a new paragraph 23 in Chapter 1, Regulation 1, which defines them as slick-forming substances with a density less than or equal to sea water, a vapour pressure of less than or equal to 0.3 kPa, solubility less than or equal to 0.1 per cent for liquids and less than or equal to 10 per cent for solids, and kinematic viscosity greater than 10 cSt at 20˚C.

OPERATIONAL RESTRICTIONS Marpol will now require control of the discharge of residues containing persistent floaters. This is established in a new paragraph 7.1.4 in Chapter 5, Regulation 13. It requires a prewash procedure, as specified in Appendix VI of Annex II, to be carried out and the residue/ water mixture generated by that procedure to be discharged to a reception facility at the port of unloading until the tank is empty. Any water subsequently introduced into the tank may be discharged into the sea.

A new paragraph 9 defines the areas to which this provision applies, giving coordinates for the limits of the North West European waters (North Sea, Irish Sea,

PROBLEMS POSED BY PERSISTENT FLOATERS

Celtic Sea, English Channel and approaches), Baltic Sea area, Western European waters and Norwegian Sea.

In Appendix IV, Section 4, paragraph 4.4.5 is amended to specify that procedures relating to the cleaning of cargo tanks, discharge of residues, ballasting and deballasting should contain instructions on how to deal with tank washings of persistent floaters, identified by the presence of ’16.2.7’ in column ‘o’ of Chapter 17 of the IBC code, when operating in the areas specified in Regulation 13.9.

A new Note 4 is added to Addendum A to Section 4, which contains the flow diagrams for the cleaning of cargo tanks and disposal of washings and ballast containing residues of category X, Y and Z substances, highlighting the addition of the requirements for persistent floaters.

Finally, a new section C is added after paragraph 21 in Appendix VI on prewash procedures. This reads:

Persistent floaters with a viscosity equal to or greater than 50 mPa.s at 20˚C and/or a melting point equal to or greater than 0˚C, shall be treated as solidifying or high-viscosity substances for the purposes of the prewash.

Where it is determined that the use of small amounts of cleaning additives would improve and maximise the removal of cargo residues during a prewash, then this should be done in consultation and with prior agreement from the reception facility.