Drain the hijiki from the soaking water. Place it in the pan, cover with spring or filtered water, bring to a boil. Simmer for a half hour or so, or until the water has evaporated. Remove from heat and let it cool to room temperature.
Clean the snow peas and blanch in boiling water for a couple of minutes. Remove from the boiling water with a slatted spoon and allow to cool.
Grate the carrots and slice the radishes very thin. Unite all the vegetables with the hajiki.
Prepare the dressing separately, by mixing all the salad ingredients together. Pour over the salad and mix well. Serve.