Colorado-based nonprofit Big Green agreed to pay 10 workers $449,999 in backpay, benefits and wages, after they were fired three years ago after trying to unionize, according to a news release on Tuesday by the National Labor Relations Board. Kimbal Musk, brother of Tesla and SpaceX founder Elon Musk, is co-founder and executive chairman of the nonprofit based in Broomfield. The settlement resolves a complaint filed three years ago by the Denver Newspaper Guild-Communications Workers of America, Local 37074, AFL-CIO, where Big Green reorganized its operations and laid off all 10 of its program coordinators and program managers.