SLOPS: Residues from vessel’s liquid cargo waste in bulk could be
Annex I regulates hydrocarbons discharges; it is in force from October 2nd of 1983 and has been amended on many occasions, in order to adapt it to current needs. Regarding Hydrocarbon cargo residues Annex I define two types:
Type A: oily tank washing residues from crude oil and ballast water polluted with crude oil.
Type B: Residues from hydrocarbons and ballast water polluted with petroleum products different from crude oil and with a density lower or equal to 1.
Marpol Annex II details the discharge criteria and measures for the control of pollution by noxious liquid substances carried in bulk; some 250 substances were evaluated and included in the list appended to the Convention; the discharge of their residues is allowed only to reception facilities until certain concentrations and conditions (which vary with the category of substances) are complied with.
MARPOL Annex II Regulations for the control of pollution by noxious liquid substances in bulk sets out a pollution categorization system for noxious and liquid substances. The four categories are:
The annex also includes a number of other requirements reflecting modern stripping techniques, which specify discharge levels for products which have been incorporated into Annex II. For ships constructed on or after 1 January 2007 the maximum permitted residue in the tank and its associated piping left after discharge is set at a maximum of 75 litres for products in categories X, Y and Z (compared with previous limits which set a maximum of 100 or 300 litres, depending on the product category).
In any case, no discharge of residues containing noxious substances is permitted within 12 miles of the nearest land.