claim in their catalogs. Also noteworthy was the point made about standarizing on-board skimmers into several categories and introduce common units that could be used throughout the world.
7) As can be seen from the SEA EMPRESS incident, aerial application of dispersants was extremely effective. But at the initial stage whether to apply dispersants or to perform mechanical recovery or to leave it to natural dispersion, that decision is very much related to the prediction as to whether oil will be hitting the shoreline. So it is very difficult to make that decision. Therefor, for this purpose, we need to improve and create a reliable drift-prediction system. PAJ has already developed several general-purpose programs for simulation, including realtime meteorological information covering several sea areas. At the Ship and Ocean foundation we are about to develope a program for prediction of changes in the properties of oil as well as prediction of drift. And we hope to have a database to include tide and current information which covers a larger area of the ocean.
8) With regard to the use of dispersants, unless they are applied within 48 hours, the effect is largely lost. But we expect some toxicity from dispersants. The fishing industry is very worried about use of dispersants. So as is done in Norway and the United States, it would be preferable to introduce a preauthorization system of use of dispersants for different regions so that we can respond very quickly. And we need to take a forward-looking attitude about the introduction of such a system. For this, it would be favorable to have sensitivity maps created for each sea area. I understand that the Marine Disaster Prevention Association is moving ahead with a project subsidized by Nippon Foundation in this regard.
9) We can fully anticipate that groups with different interests will propose different methods for cleaning the shorelines. Therefore, although it is very difficult, it is a must to have an overall evaluation made, and to have an agreement beforehand as to what should be the priority for that particular shore.
10) In the SEA EMPRESS incident, concrete mixers were used for cleaning up the cobbles. In Japan it was also reported that vacuum trucks and jet pumps of fire engines and barges were used for collecting the high-viscosity oil. I don't think we will be able to immediately have such equipment, but what is desired is to have the documentation for such equipment and how it was used, for future reference.
11) We need to consider the need for temporary storage facilities for the oily waste, and also for final disposal. The collected materials, by law now in Japan, are handled as industrial waste. In the U.K., oily sand is used for road construction, mixed together with asphalt. Or it isreused after biodegradation. Therefore, I think we need study how to reduce the amount of waste by some method.
12) It is noteworthy to having a contract beforehand with the local fishing boats for the operation. This was mentioned by several speakers.
13) Now the report on recovery of marine life affected by oil pollution, and the increase in salmon returning in the year following the incident in Alaska, even exceeding the populations of previous years, is something that gives us hope. Shoreline cleaning, such as high-temperature, high-pressure water washing, does give a better appearance, but it delays ecological recovery. Therefore, though somewhat incomplete, resorting to normal-temperature, low-pressure water washing, and leaving the rest to the natural cleaning process, and to promote biodegradation by adding fertilizer would facilitate ecological recovery. And I think we really should take to heart the meaning of "How clean is clean?" So I think we should make efforts so that cleanup methods using microorganisms would really be established and approved.
Finally, I would like to take this opportunity to express my appreciation to the guest speakers, who have given their very valuable presentations and discussion, as well as the observers, who listened for many long hours.
With this, I would like to close these very significant sessions. Thank you.
