A model for simulating the behavior of sediment plumes from deepwater mining and their re sulting environmental effect is presented. This paper contains the complete model formulation and scenario simulations. The sediment transport model includes both the near field (plume dy namics) and the far-field (passive advection-diffusion) phases. The model can handle both up ward and downward releases. The model also takes into account the possible separation of sediments from the main plume. The model is three-dimensional and takes ambient current variations and stratification into account. For simulating the behavior of chemicals attached to sediments, three types of chemicals are considered: heavy metal, organic chemical, and mineral. The main difference between the different types is how they partition between being attached to the sediments and dissolved in water. The model simulates the transport of chemicals at tached to the sediment as well as the chemicals dissolved in water. The scenario simulations as sess the effect on biological life due to entombment by deposited sediments. The lightattenuation and the resulting effect on photosynthesis in the water column due to sediments are also simulated.

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In this paper, we deal with the hydrodynamic properties of VOS (volunteer observing ship) to lend itself for direct monitoring of seawater. The original depth of seawater sampled at the stern at mid draft of the ship of opportunity for monitoring was estimated by model ship in an experimental basin. We inject dye from the upstream of the model ship and pick the water up from the inlet (sea chest), and then the density occupation rate of dye in the water taken from the fixed inlet is analyzed by use of a spectrophotometer. By iterating the same sort of meas urements changing the location of the dye injection point, we obtained a contour map of the oc cupation rate of dye. Furthermore, CFD (computational fluid dynamics) was employed to confirm the model experiment. The experiment in regular waves was conducted to make above method extend to be applicable in real ocean condition. In addition, full size numerical compu tation was performed to validate the new method in its practical use. Results showed that the sampled water comes from near the water surface. In the scale of ferry being used for monitor ing, it was predicted that water at -0.7m is drawn into the inlet at -4 to -5m in depth.

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This paper qualitatively surveys tendency of duties or requests, which foreign states imposed with consent for a Japanese research organization to conduct marine scientific research (MSR) in foreign Exclusive Economic Zones (EEZ) in accordance with United Nations Convention on the Law of the Sea (UNCLOS). MSR conducted only in 1999 or later was reviewed. The most common request is for cruise reports. In terms of requests of cruise reports and data or samples, few coastal states changed. Recently, slightly fewer states request embarkation on a research vessel as a right based on UNCLOS than before. More and more states require a particular ap plication format.

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I have contrived an Apparatus producing a great deal of compressed air. (See Fig.l, Fig.2) The mass of Float is much larger than the mass of Weight, so the Float usually floats on the sea and the Weight is alweys in the ai. As the sea surface gets up-and-down, the Wheel recip rocates and the Pumps compress air. The compressed air is pressed into the same Air Receiver from a pair of Piston-pumps. By the way, it is desired that the Float keeps up big vibration in order to produce the com pressed air efficiency. For this purpose, the value of ***** (See 3.1 formulas (1), (8)) be tween 0.2 and 0.25 is satisfactory. Then I design a right Apparatus and simulate the movement of the Float in the case of wave height 1 (m) and wave period 7 (sec). This example is shown in Chapter 4. (See Fig.4, Table 1) On the other hand, the pressure of the compressed air is related to the radius of cylinders in the piston-pumps. In chapter 5.1 discuss how the movement of the Float produces 8000m^3 com pressed air of 2 atm (radius 0.2m) or 8 atm (radius 0.08m). These are shown by Figures, a Graph and Tables. (See Fig.5, 6, 7 & Table 1, 2)

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