My mother's parents are "buried" on Mt Rainier. We hired a private pilot who is experienced at scattering ashes from his small airplane. I think it's technically illegal to scatter ashes in national parks and in lakes and rivers, so it's a hush-hush thing, but as long as it's done quietly and respectfully, nobody seems to mind. As a family, we scattered my father's ashes in the Spokane River (per his request), and a nice young man approached us and said "Are you chumming?" and we stopped and smiled, and told him what we were doing. He was embarrassed and he blushed beet red, so we all gave him a hug.
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