Around Rausu Town, where deep seawater (DSW) has been pumped since 1995 (in fullscale since 2005), local brand of cheese production has been traditionally popular because cattle breeding is a big business. As application of DSW has producedmany characteristic products (particularly fermented ones such as soy been sauceor paste) in other DSW- facilitated areas, the authors made Gouda cheese and yogurt from low milk with deep seawater (DSW) or concentrated DSW (c-DSW) and compared their qualities with DSW-free products. In Gouda cheese, four kinds of products were made with the combinations of low milk or that mixed with DSW (to 2% ofthe total volume) x c-DSW or saltwater as brine. All of the products were vacuum-packed and ripened for 25 days in 4°C and 42 days in 10°C. Among the four products, no significant difference was detected in the percentage of water soluble nitrogen per total nitrogen. When (c-) DSW was added to both low milk andbrine, the free amino acid content was higher than DSW-free product. Surface of the cheese with a brine of c-DSW melt. Yogurt was made by mixture of a lactobacillus starter and fermentation at 42°C for 6 hours after adding DSW (to 0, 2, or 4% of the total volume) to sterilized and chilled 10% skim milk solution. Yogurt containing DSW showed some trends of decrease in pH, increase in acidity andthe number of lactobacillus. Regretfully, little improvement was achieved by adding DSW to both Gouda cheese and yogurt in sensory test. Particularly c-DSW madethe product bitter when it was used as brine.

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A technology of hastening the seawater exchange using deep seawater (DSW, known as clean and cold seawater) was tested in a case study on Rausu Fishing Port using a hydraulic model and a numerical simulation. The technology was proposed by the authors as follows in 2006. When cold seawater is continuously emitted in the state of a buoyant jet along the bottom of an anchorage in a port, the jet increases its width in the shape of a fan immediately by entraining the surroundingseawater. Although the jet flow velocity decreases with the increase in the entrainment velocity, the buoyant jet expands in the shape of a concentric circle. When the buoyant jet flows out through the lower layer of the port, outside freshseawater flows into the port through the upper layer in order to compensate the flux. At Rausu Fishing Port, Hokkaido, water quality was reported to be worsenedparticularly at the west anchorage in autumn, but 4, 560 ton/day of DSW has been pumped from a depth of 350m for industrial use since 2006. In the present study, a hydraulic model (1.5×8×1m, with topography in the port and its vicinity of 1/250 in scale) was used with a wave producer assuming the use of emission pipes with inner diameter 25 or 50 cm. The numerical simulations were conducted using a 3-dimension fluid analysis model in the case of emission of 5, 000 t/day of DSW (5°C, 33.3 psu) as a buoyant jet at an initial velocity of 1.18 m/s into the west anchorage (12°C, 33.5 psu representing the autumnal condition) toward its center. The amount of seawater exchange was calculated to be 2 to 12 times largerthan that obtained at the spring tide. The validity of the technology was discussed.

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The present study identified the characteristic attached diatoms derived from Shiretoko Rausu Deep Seawater (DSW) pumped from a depth of 218 m in Okhotsk Sea. Diatom samples were collected from a DSW tank seasonally from December 2004 to December 2005 and identified using light and scanning electron microscopy. A totalof 11 species in 7 genera were recorded. The most common taxa encountered were Amphora sp. and Cocconeis sp. 1. Amphora sp. was dominant from winter to spring and thereafter decreased gradually, whereas Cocconeis pinnata and Cocconeis sp. 1 increased from spring to summer. Navicula sp. 1 and Nitzschia tubicola were common but decreased in summer. Tabularia investiens was in constant occurrence. Theoverall attached diatom flora in Shiretoko Rausu DSW was different from those previously observed by the authors in other DSW facilities (Namerikawa, Nyuuzen and Muroto) in Japan. In the present paper, morphologic and taxonomic comments were given for the above 5 species as well as the other two species, Achnanthes sp. and Tryblionella sibula.

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During the food process of the sea urchin, Strongylocentrotus intermedius, alum solution of the artificial seawater (ASW) base is used to prevent the collapse of gonads and to extend preservation period, but it enhances endemic bitterness when used in higher concentrations. In this experiment, bacterial features, tasteand outlook of gonads were compared after treated with four kinds of alum solutions; 0.2, 0.5 and 1.0% on the base of deep seawater (DSW, pipelined from a depthof 218 m off Rausu) and 1.0% on the base of ASW (traditionally used). Each unit (120 g) of gonads were kept in a refrigerator (5°C) after the alum treatments for ten minutes. Number of general bacteria (NGB) in the gonads was kept under10, 000/g in all blocks for ten days though the highest value 23, 000/g appeared on ASW block on the fifteenth day. Occurrence of coliform bacteria (CB) was negativein all blocks. These bacterial features cleared the criteria for raw fish andshellfish materials (less than 100, 000/g in NGB and negative in CB) ruled in Japanese Food Hygiene Law. In the sensory test, practiced on the fourth day, all ofDSW blocks (particularly with lower concentration of alum) got higher scores in taste, outlook and total evaluations than the ASW block. Therefore, use of DSW can eliminate the elaboration of preparing ASW and improve the taste of gonads bylowering the alum concentration.

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At Rausu Town, northeast of Hokkaido, collection of a high-priced edible sea urchin Strongylocentrotus intermedius is prohibited for resource conservation during the spawning season from July to September. Furthermore, the removed maturing gonads are not good for commercial use because they easily ‘melt’ (collapsed). However, the urchin gonad is a potential natural food product particularly in the summer season in which most abundant tourists visit the town in a year. During summers in 2003 and 2004, maturation control was tried by culturing the collectedsea urchins in land-based tank (0.5 ton in volume) using deep seawater (DSW) colder than surface seawater (SSW). In June 2003, half of the sea urchins (>50 mm in diameter, N = 240 in June 2003) were fed with kelp, while the others were keptunfed. Gonads of fed, unfed and wild sea urchins were biweekly evaluated using standard criteria comprised of 5 stages (I to V). The deep seawater was pumped from a depth of 218 m, 1.4 km off Chienbetsu Fishing Port and the water temperature was kept between 2 and 4°C by circulating and chilling. In 2003 (2004), the most valuable gonad stage III accounted for 47 (70) % at the commencement of stock-cultured on June 25^th (May 11 ^th) and lowered below 10% on August 20^th (September 14^th) in fed andon August 20th (August 17^th) in unfed sea urchins. On July 23rd (August 17^th), when gonads lowered below 10% in wild urchins, the ratio ofstage III accounted for 27 (35) % in fed and 40 (10) % in unfed sea urchins. In asensory test conducted in 2004, gonads in stage III of both fed andunfed sea urchins marked fine scores (higher than middle among five ranks) on taste and outlook till July 6^th (stock-cultured for 56days).

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In order to promote the utilization of deep seawater (DSW) in Rausu Town, northeastern Hokkaido, it is necessary to ascertain in advance the extent to which related industries will influence the production value and other aspects of the town. In the present paper, the process of the feasibility study for the promotion and post-evaluation on the implemented programs were reported. In the feasibility study, characteristics of the current industrial structure were analyzed to clarify the positioning of local marine industries and the income levels of the residents using a regional input-output table. Then the direction of industrial promotion necessary to realize the vision for the future was presented. In the second, seven regional promotion scenarios (four of them are related to DSW) along with twelve specific programs and target values were drawn up to give shape to the industrial promotion policy. Specific target values were given to eight of the twelve programs, and those target values were discussed by the Rausu Marine Vision Council to ensure their realization. Then, the direct effect of the eight programs was examined, and the effect was regarded as the final demand increase in input-output analysis to estimate the economic impacts on the regional economy. For programs that had already been implemented, the degree of goal attainment as well as the problems and challenges encountered were clarified for reevaluation.

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