As with any other incident that will eventually involve liability, compensation and reimbursement issues, it is essential that personnel onboard maintain a comprehensive, detailed record of events. Apart from detailing all actions taken on board, the log should also contain a record of communications with outside authorities, owners, and other parties, as well as a brief summary of information passed and received, and decisions made. The observer movement of the spilled oils should also be recorded together with details of prevailing wind, current and sea conditions. When the spill occurs in port, a brief description of areas contaminated by the oil will be useful together with information on other craft and facilities likely to be affected.
Written data should be supported by photographs whenever possible although care should be taken to ensure that the use of cameras does not contravene local regulations.
Brief details of any response initiated by shore authorities should also be recorded and, when known, information on numbers of personnel engaged in the clean-up as well as type and quantity of clean-up equipment and material being used. It may be particularly useful to collect samples of all the different types of oil carried on board as well as a sample of the spilled oil, especially in cases where it is suspected that not all the oil pollution comes from one source. If the ship is not responsible for a particular spill, photographs of the hull and deck may help in verifying this. Similarly, if another ship is observed spilling oil, this should be photographed, if possible, and reported on sighting.
Photographs of the oil on the sea close to the tanker may help in ascertaining the magnitude of the spill. If shoreline contamination occurs, it is recommended that an independent detailed examination of the shore be made to determine the uniformity of the oil deposited and the extent to which the shore may be polluted by more than one type of oil. The P & I Club correspondent or an appointed surveyor will be able to assist with these measures and arrange for representative samples of the deposited oil to be taken.
When taking samples, which may eventually be required as evidence in legal proceedings, it is essential to establish their authenticity. Collection of samples should therefore be witnessed and containers should be properly sealed and labelled. As pollution control authorities will probably also require samples for their own use, it may be appropriate for sampling to be undertaken as a joint exercise with samples being split between the two parties and authenticated at the same time.