The book that this movie is based off of, O Rugged Land of Gold, was written by my great grandmother (under the pen name Martha Martin, real name was Helen Bolyan). Lloyd's name is really Clyde, my grandfather. I asked him after the movie first came out and we watched it, if he was as much of a brat as he was portrayed in the movie and he told me he was always a good boy. But the twinkle in his eye made me think otherwise :-)
My grandfather was born in 1915. The book states that my great grandmother complied events from her life to write the story. The movie loosely portrayed the book, for example the set it in the 50s. My dad was born in 43, so my grandpa couldn't have been a little boy in the 50s :-) There really was a mine. It's located on the Chichagof Island. You can read how it came to be if you Google "Cobol Chichagof Island". There is a Juneau parks and rec link about George A Bolyan (Don Martin) that my grandfather wrote. It won't let me post the actual link.
Keep in mind the movie was filmed in New Zealand, there are no possums in Alaska :-)